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Re: Bulk Mailing Performance

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  • Robert Schetterer
    ... Hi look on list archives about tuning stuff also read http://www.postfix.org/TUNING_README.html at last , there are two side deliver in/out for out ,there
    Message 1 of 30 , Sep 2, 2012
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      Am 02.09.2012 11:43, schrieb Sam Jones:
      > More to satisfy my own curiosity than anything else, I'm wondering about
      > the performance that could be squeezed out of Postfix in a bulk mailing
      > capacity.
      >
      > I have a client that currently uses and ESP who have an astounding
      > throughput of up to a million messages per hour. This brought up a
      > discussion about high-performance MTAs and tuning and the general
      > comments I'm hearing are that things like Postfix, Exim, Sendmail &
      > are just not man enough for such a task and the absolute best you could
      > expect from any of them is about 100k messages per hour.
      >
      > Now, I like to wipe out the fact from fiction because people like
      > PowerMTA are looking to sell their products and it would be in their
      > interest to neglect that any MTA (Postfix/Exim/Sendmail) could be set up
      > in a way that would easily rival their product.
      >
      > Can anyone on the list tell me if it's possible to performance tune
      > Postfix to a point where it could complete with this and possible
      > strategies?
      >
      > Kind thanks
      >

      Hi look on list archives about tuning stuff

      also read

      http://www.postfix.org/TUNING_README.html

      at last , there are two side deliver in/out

      for out ,there are things you need to find out about
      the recipients mail servers, cause many of them have limits about get
      mail from the same ip adress per time periods,and/or do greylisting and
      other filter stuff, so its not only a question how to tune your own
      postfix ( which may always be possible to goal your needs, depending on
      hardware, filesystems network etc )
      for massive bulk mails sometimes multiple instance postfix or a cascade
      with smtp fallback postfix servers is used for fasten deliver out mail.
      Also possible smtp via loadbalancer etc.

      At last there are a lot other recommands ( whitelisting at big mailers ,
      use dkim and spf dmarc etc ) doing massive mail which arent related
      directly to the mailserver software you use, for sure postfix will never
      be the performance problem if setup right to your "massive" needs.
      In fact postfix is widly used for massive mail.

      --
      Best Regards
      MfG Robert Schetterer
    • Viktor Dukhovni
      ... Running a high volume bulk email platform is not a software problem. It is a logistics problem. Enrolling on the whitelists and feedback loops of various
      Message 2 of 30 , Sep 2, 2012
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        On Sun, Sep 02, 2012 at 10:43:07AM +0100, Sam Jones wrote:

        > More to satisfy my own curiosity than anything else, I'm wondering about
        > the performance that could be squeezed out of Postfix in a bulk mailing
        > capacity.

        Running a high volume bulk email platform is not a software problem.
        It is a logistics problem. Enrolling on the whitelists and feedback
        loops of various large email providers, handling bounce-backs,
        jumping through rate-limit hoops, ...


        > I have a client that currently uses and ESP who have an astounding
        > throughput of up to a million messages per hour.

        This is not astounding, a single ~2003 Dell 1850 Postfix server
        was measured by me at ~300 msgs/sec of deliveries to real users
        with nothing but a simple MegaRAID controller (with battery cache)
        striping two SCSI disks. This would go another factor of 2 faster
        on today's commodity servers, but the real issue is finding peers
        who'll accept your mail at that rate.

        > discussion about high-performance MTAs and tuning and the general
        > comments I'm hearing are that things like Postfix, Exim, Sendmail &
        > are just not man enough for such a task and the absolute best you could
        > expect from any of them is about 100k messages per hour.

        Many bulk email services in fact use Postfix, Exim, ... The MTA
        software is often not the bottleneck. They split bulk deliveries
        over many machines (or lots of IPs on the same machine) and tune
        to avoid throttling by the ESP over and above all other concerns.
        Raw MTA performance is rarely a factor.

        > Now, I like to wipe out the fact from fiction because people like
        > PowerMTA are looking to sell their products and it would be in their
        > interest to neglect that any MTA (Postfix/Exim/Sendmail) could be set up
        > in a way that would easily rival their product.

        Bulk email is a logistics exercise. When you choose an bulk email
        delivery service, you're buying their logistics skills and their
        reputation with mailbox providers (Gmail, Hotmail, Yahoo, ...)

        > Can anyone on the list tell me if it's possible to performance tune
        > Postfix to a point where it could complete with this and possible
        > strategies?

        Wrong question.

        --
        Viktor.
      • Sam Jones
        ... I really appreciate the post Viktor. Thought provoking and clear. I guess what I m querying in a way is some of the sales blurb from people like PowerMTA &
        Message 3 of 30 , Sep 2, 2012
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          On Sun, 2012-09-02 at 15:39 +0000, Viktor Dukhovni wrote:
          > On Sun, Sep 02, 2012 at 10:43:07AM +0100, Sam Jones wrote:
          >
          > > More to satisfy my own curiosity than anything else, I'm wondering about
          > > the performance that could be squeezed out of Postfix in a bulk mailing
          > > capacity.
          >
          > Running a high volume bulk email platform is not a software problem.
          > It is a logistics problem. Enrolling on the whitelists and feedback
          > loops of various large email providers, handling bounce-backs,
          > jumping through rate-limit hoops, ...
          >
          >
          > > I have a client that currently uses and ESP who have an astounding
          > > throughput of up to a million messages per hour.
          >
          > This is not astounding, a single ~2003 Dell 1850 Postfix server
          > was measured by me at ~300 msgs/sec of deliveries to real users
          > with nothing but a simple MegaRAID controller (with battery cache)
          > striping two SCSI disks. This would go another factor of 2 faster
          > on today's commodity servers, but the real issue is finding peers
          > who'll accept your mail at that rate.
          >
          > > discussion about high-performance MTAs and tuning and the general
          > > comments I'm hearing are that things like Postfix, Exim, Sendmail &
          > > are just not man enough for such a task and the absolute best you could
          > > expect from any of them is about 100k messages per hour.
          >
          > Many bulk email services in fact use Postfix, Exim, ... The MTA
          > software is often not the bottleneck. They split bulk deliveries
          > over many machines (or lots of IPs on the same machine) and tune
          > to avoid throttling by the ESP over and above all other concerns.
          > Raw MTA performance is rarely a factor.
          >
          > > Now, I like to wipe out the fact from fiction because people like
          > > PowerMTA are looking to sell their products and it would be in their
          > > interest to neglect that any MTA (Postfix/Exim/Sendmail) could be set up
          > > in a way that would easily rival their product.
          >
          > Bulk email is a logistics exercise. When you choose an bulk email
          > delivery service, you're buying their logistics skills and their
          > reputation with mailbox providers (Gmail, Hotmail, Yahoo, ...)
          >
          > > Can anyone on the list tell me if it's possible to performance tune
          > > Postfix to a point where it could complete with this and possible
          > > strategies?
          >
          > Wrong question.
          >
          I really appreciate the post Viktor. Thought provoking and clear.

          I guess what I'm querying in a way is some of the sales blurb from
          people like PowerMTA & GreenArrow and the remarks they make about open
          source solutions like Postfix etc. This one in particular: "Open source
          Mail Transfer Agents (MTAs) often max out between 20 and 30 thousand
          messages per hour. GreenArrow can send 300,000 messages per hour—more
          than ten times as fast."

          If we strip this back to hypothetical and assume a perfect world without
          any issues like rate limiting and rejection, small emails with nomay
          restrictions or network issues with the recipient MX's, is the above
          statement plausibly true?

          I'm assuming - and I've not yet looked deeply at this - that there is
          probably a way to get Postfix to run parallel instances to improve
          delivery speed.
        • Wietse Venema
          ... That s 7 deliveries per second, a number that you might get with an MTA that makes one connection at a time (Sendmail, Exim). You get larger numbers with
          Message 4 of 30 , Sep 2, 2012
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            Sam Jones:
            > I guess what I'm querying in a way is some of the sales blurb from
            > people like PowerMTA & GreenArrow and the remarks they make about open
            > source solutions like Postfix etc. This one in particular: "Open source
            > Mail Transfer Agents (MTAs) often max out between 20 and 30 thousand
            > messages per hour.

            That's 7 deliveries per second, a number that you might get with
            an MTA that makes one connection at a time (Sendmail, Exim).

            You get larger numbers with parallel deliveries. Those are built-into
            Postfix/qmail/etc. With MTAs such as Sendmail/Exim/etc. you get
            parallel deliveries by using parallel submission.

            Once you reach the file system performance limit, Postfix/qmail/etc.
            require parallel submission as well, with different MTAs running
            on top of independent file systems.

            As Victor says, it is not primarily an MTA problem. The technical
            problems are a matter of proper diagnosis and appropriate tuning.

            Wietse
          • Lorens Kockum
            The exact same question was sent by someone calling himself Ron White to the exim mailing list at almost exactly the same time. Peddling one s services by
            Message 5 of 30 , Sep 2, 2012
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              The exact same question was sent by someone calling himself
              "Ron White" to the exim mailing list at almost exactly the same
              time. Peddling one's services by soliciting comparisons with
              competitors is so passé . . .
            • John Peach
              On Sun, 2 Sep 2012 22:46:10 +0200 ... I find it rather useful; lets me know what I should be blocking.... ... -- John
              Message 6 of 30 , Sep 2, 2012
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                On Sun, 2 Sep 2012 22:46:10 +0200
                Lorens Kockum <postfix-users-4329@...> wrote:

                > The exact same question was sent by someone calling himself
                > "Ron White" to the exim mailing list at almost exactly the same
                > time. Peddling one's services by soliciting comparisons with
                > competitors is so passé . . .

                I find it rather useful; lets me know what I should be blocking....
                >


                --
                John
              • Dario Cavallaro
                ... In my experience, I have never had problems with performances in the past with Postfix. Though I had stability issues, but just because we reached out the
                Message 7 of 30 , Sep 2, 2012
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                  Il 02/09/2012 11:43, Sam Jones ha scritto:
                  > More to satisfy my own curiosity than anything else, I'm wondering about
                  > the performance that could be squeezed out of Postfix in a bulk mailing
                  > capacity.
                  >
                  > I have a client that currently uses and ESP who have an astounding
                  > throughput of up to a million messages per hour. This brought up a
                  > discussion about high-performance MTAs and tuning and the general
                  > comments I'm hearing are that things like Postfix, Exim, Sendmail &
                  > are just not man enough for such a task and the absolute best you could
                  > expect from any of them is about 100k messages per hour.
                  >
                  > Now, I like to wipe out the fact from fiction because people like
                  > PowerMTA are looking to sell their products and it would be in their
                  > interest to neglect that any MTA (Postfix/Exim/Sendmail) could be set up
                  > in a way that would easily rival their product.
                  >
                  > Can anyone on the list tell me if it's possible to performance tune
                  > Postfix to a point where it could complete with this and possible
                  > strategies?
                  >
                  > Kind thanks
                  >
                  >
                  In my experience, I have never had problems with performances in the
                  past with Postfix. Though I had stability issues, but just because we
                  reached out the limit of opened files (OS tuning). And it was during a
                  spam attack (probably around a milion email per hour during attack).

                  Hope this helps.

                  Cheers,
                  Dario "subbia" Cavallaro
                • Viktor Dukhovni
                  ... As I said, I measured 300 msgs/sec with Postfix on relatively modest hardware in 2003. This is not too difficult, just configure sufficient output
                  Message 8 of 30 , Sep 2, 2012
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                    On Sun, Sep 02, 2012 at 07:14:35PM +0100, Sam Jones wrote:

                    > I guess what I'm querying in a way is some of the sales blurb from
                    > people like PowerMTA & GreenArrow and the remarks they make about open
                    > source solutions like Postfix etc. This one in particular: "Open source
                    > Mail Transfer Agents (MTAs) often max out between 20 and 30 thousand
                    > messages per hour. GreenArrow can send 300,000 messages per hour?more
                    > than ten times as fast."

                    As I said, I measured 300 msgs/sec with Postfix on relatively modest
                    hardware in 2003. This is not too difficult, just configure sufficient
                    output concurrency, and provide a low latency disk (battery cache
                    striped RAID).

                    With RAM disk (a queue-manager bottleneck analysis, circa five
                    years ago) Postfix yielded ~3000 msgs/sec on a dual Opteron box
                    delivering to the discard transport. So that's your ceiling if you
                    provide sufficient disk and network bandwidth, eventually the queue
                    manager runs out of CPU, but this is at rates approaching 10 million
                    messages an hour.

                    The throughput numbers are not that interesting anymore, I go for
                    reliability, security and flexibility. I also go for a solid
                    architecture that degrades well under load, and that's why I
                    really like Postfix, but this is a difficult point to make,
                    most people are not in a position to understand why Postfix
                    stands out in this regard.

                    --
                    Viktor.
                  • DTNX Postmaster
                    ... In other words, if we strip this back to hypothetical and assume a perfect world without any issues , this GreenArrow maxes out at 300,000 messages per
                    Message 9 of 30 , Sep 2, 2012
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                      On Sep 3, 2012, at 03:56, Viktor Dukhovni wrote:

                      > On Sun, Sep 02, 2012 at 07:14:35PM +0100, Sam Jones wrote:
                      >
                      >> I guess what I'm querying in a way is some of the sales blurb from
                      >> people like PowerMTA & GreenArrow and the remarks they make about open
                      >> source solutions like Postfix etc. This one in particular: "Open source
                      >> Mail Transfer Agents (MTAs) often max out between 20 and 30 thousand
                      >> messages per hour. GreenArrow can send 300,000 messages per hour?more
                      >> than ten times as fast."
                      >
                      > As I said, I measured 300 msgs/sec with Postfix on relatively modest
                      > hardware in 2003. This is not too difficult, just configure sufficient
                      > output concurrency, and provide a low latency disk (battery cache
                      > striped RAID).
                      >
                      > With RAM disk (a queue-manager bottleneck analysis, circa five
                      > years ago) Postfix yielded ~3000 msgs/sec on a dual Opteron box
                      > delivering to the discard transport. So that's your ceiling if you
                      > provide sufficient disk and network bandwidth, eventually the queue
                      > manager runs out of CPU, but this is at rates approaching 10 million
                      > messages an hour.
                      >
                      > The throughput numbers are not that interesting anymore, I go for
                      > reliability, security and flexibility. I also go for a solid
                      > architecture that degrades well under load, and that's why I
                      > really like Postfix, but this is a difficult point to make,
                      > most people are not in a position to understand why Postfix
                      > stands out in this regard.

                      In other words, if 'we strip this back to hypothetical and assume a
                      perfect world without any issues', this 'GreenArrow' maxes out at
                      300,000 messages per hour. Postfix can send 10,8 million messages per
                      hour, more than 35 times as fast*.

                      Lies, damn lies, and vendor benchmarks, heh.

                      Cya,
                      Jona

                      --

                      * Tests performed in an optimized lab environment. Operational
                      restrictions may apply in real world environments.
                    • Stefan Foerster
                      ... My desktop machine - the very same one I m writing this mail on - is currently delivering 65 messages per second to a smtp-sink. On a single 2TB SATA drive
                      Message 10 of 30 , Sep 2, 2012
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                        * Sam Jones <sam_jones90@...>:
                        > I guess what I'm querying in a way is some of the sales blurb from
                        > people like PowerMTA & GreenArrow and the remarks they make about open
                        > source solutions like Postfix etc. This one in particular: "Open source
                        > Mail Transfer Agents (MTAs) often max out between 20 and 30 thousand
                        > messages per hour. GreenArrow can send 300,000 messages per hour—more
                        > than ten times as fast."

                        My desktop machine - the very same one I'm writing this mail on - is
                        currently delivering 65 messages per second to a smtp-sink. On a
                        single 2TB SATA drive that will probably suffer a heart attack if you
                        even so much as threaten it with more than 20 IOPS/s. That's while
                        watching a 1080p video (footage from my last holiday). With no tuning
                        whatsoever.

                        Granted, not a real world use case, but still, don't trust everything
                        you read on the web.


                        Stefan
                      • Ralf Hildebrandt
                        ... The problem is mostly on the receiving side, when the receiving system starts throtteling you. ... I once sent 2096/min*60min = 125.760mails/minute on
                        Message 11 of 30 , Sep 3, 2012
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                          * Sam Jones <sam_jones90@...>:

                          > More to satisfy my own curiosity than anything else, I'm wondering about
                          > the performance that could be squeezed out of Postfix in a bulk mailing
                          > capacity.

                          The problem is mostly on the receiving side, when the receiving system
                          starts throtteling you.

                          > I have a client that currently uses and ESP who have an astounding
                          > throughput of up to a million messages per hour. This brought up a
                          > discussion about high-performance MTAs and tuning and the general
                          > comments I'm hearing are that things like Postfix, Exim, Sendmail &
                          > are just not man enough for such a task and the absolute best you could
                          > expect from any of them is about 100k messages per hour.

                          I once sent 2096/min*60min = 125.760mails/minute on mail.python.org
                          and there the generation of the mails is the limiting factor.

                          --
                          Ralf Hildebrandt
                          Geschäftsbereich IT | Abteilung Netzwerk
                          Charité - Universitätsmedizin Berlin
                          Campus Benjamin Franklin
                          Hindenburgdamm 30 | D-12203 Berlin
                          Tel. +49 30 450 570 155 | Fax: +49 30 450 570 962
                          ralf.hildebrandt@... | http://www.charite.de
                        • Ralf Hildebrandt
                          ... Absolutely. -- Ralf Hildebrandt Geschäftsbereich IT | Abteilung Netzwerk Charité - Universitätsmedizin Berlin Campus Benjamin Franklin Hindenburgdamm 30
                          Message 12 of 30 , Sep 3, 2012
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                            * Viktor Dukhovni <postfix-users@...>:

                            > Running a high volume bulk email platform is not a software problem.
                            > It is a logistics problem. Enrolling on the whitelists and feedback
                            > loops of various large email providers, handling bounce-backs,
                            > jumping through rate-limit hoops, ...

                            Absolutely.

                            --
                            Ralf Hildebrandt
                            Geschäftsbereich IT | Abteilung Netzwerk
                            Charité - Universitätsmedizin Berlin
                            Campus Benjamin Franklin
                            Hindenburgdamm 30 | D-12203 Berlin
                            Tel. +49 30 450 570 155 | Fax: +49 30 450 570 962
                            ralf.hildebrandt@... | http://www.charite.de
                          • Stan Hoeppner
                            ... In all fairness, given your perfect world criteria, this ESP would be moving a lot more mail as well, with no restrictions on the outbound pipe or at the
                            Message 13 of 30 , Sep 3, 2012
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                              On 9/3/2012 12:02 AM, DTNX Postmaster wrote:

                              > In other words, if 'we strip this back to hypothetical and assume a
                              > perfect world without any issues', this 'GreenArrow' maxes out at
                              > 300,000 messages per hour. Postfix can send 10,8 million messages per
                              > hour, more than 35 times as fast*.

                              In all fairness, given your "perfect world" criteria, this ESP would be
                              moving a lot more mail as well, with no restrictions on the outbound
                              pipe or at the receiver.

                              But as others have correctly pointed out, the issue here isn't MTA
                              performance, it's administrative performance. The last thread I
                              responded to demonstrates this. The big advantage ESPs have is their
                              established relationships with the freemailers and other large mailbox
                              providers. These allow them greater throughput than the unwashed bulk
                              sender, at least into the receiver's initial queue.

                              --
                              Stan
                            • DTNX Postmaster
                              ... They aren t my perfect world criteria, but a direct quote from Sam Jones earlier buzzword compliant reply. It was meant to illustrate the often ridiculous
                              Message 14 of 30 , Sep 3, 2012
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                                On Sep 3, 2012, at 13:05, Stan Hoeppner wrote:

                                > On 9/3/2012 12:02 AM, DTNX Postmaster wrote:
                                >
                                >> In other words, if 'we strip this back to hypothetical and assume a
                                >> perfect world without any issues', this 'GreenArrow' maxes out at
                                >> 300,000 messages per hour. Postfix can send 10,8 million messages per
                                >> hour, more than 35 times as fast*.
                                >
                                > In all fairness, given your "perfect world" criteria, this ESP would be
                                > moving a lot more mail as well, with no restrictions on the outbound
                                > pipe or at the receiver.
                                >
                                > But as others have correctly pointed out, the issue here isn't MTA
                                > performance, it's administrative performance. The last thread I
                                > responded to demonstrates this. The big advantage ESPs have is their
                                > established relationships with the freemailers and other large mailbox
                                > providers. These allow them greater throughput than the unwashed bulk
                                > sender, at least into the receiver's initial queue.

                                They aren't my perfect world criteria, but a direct quote from Sam
                                Jones' earlier buzzword compliant reply.

                                It was meant to illustrate the often ridiculous nature of vendor
                                benchmarks, how useless they are in real world situations, and
                                therefore how silly it is to pick software based on theoretical limits
                                you will most likely never hit.

                                Not enough sarcasm, I guess ;-)

                                Cya,
                                Jona
                              • Jose-Marcio Martins da Cruz
                                ... Not really ridiculous. All those benchmarks are interesting, as they represent, say, the intrinsic performance of the software . The problem is to tell
                                Message 15 of 30 , Sep 3, 2012
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                                  DTNX Postmaster wrote:

                                  >
                                  > They aren't my perfect world criteria, but a direct quote from Sam
                                  > Jones' earlier buzzword compliant reply.
                                  >
                                  > It was meant to illustrate the often ridiculous nature of vendor
                                  > benchmarks, how useless they are in real world situations, and
                                  > therefore how silly it is to pick software based on theoretical limits
                                  > you will most likely never hit.

                                  Not really ridiculous. All those benchmarks are interesting, as they represent,
                                  say, the "intrinsic performance of the software". The problem is to tell (for
                                  the vendor) and to take into account (for the reader) the conditions at which
                                  the benchmark was done.

                                  But, sure, two pieces of software can be compared only if measurings are done
                                  with the same conditions. And one software which has better "intrinsic
                                  performance" may not be better in real world conditions.


                                  --
                                • Sam Jones
                                  ... Yes, it was. Well done. The question applied to both MTA s and funny enough, the use of Aliases on the internet is nothing new. Thanks to those that
                                  Message 16 of 30 , Sep 3, 2012
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                                    On Sun, 2012-09-02 at 22:46 +0200, Lorens Kockum wrote:
                                    > The exact same question was sent by someone calling himself
                                    > "Ron White" to the exim mailing list at almost exactly the same
                                    > time. Peddling one's services by soliciting comparisons with
                                    > competitors is so passé . . .
                                    >
                                    Yes, it was. Well done. The question applied to both MTA's and funny
                                    enough, the use of Aliases on the internet is nothing new.

                                    Thanks to those that contributed useful information. I think it's safe
                                    to say that the sales blurb is looking at a very basic scenario.
                                  • Daniel L. Miller
                                    ... [...] ... Knowing absolutely nothing about the software mentioned - I would say there is a difference between messages SENT vs messages DELIVERED. I
                                    Message 17 of 30 , Sep 3, 2012
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                                      On 9/2/2012 11:14 AM, Sam Jones wrote:
                                      > On Sun, 2012-09-02 at 15:39 +0000, Viktor Dukhovni wrote:
                                      >> On Sun, Sep 02, 2012 at 10:43:07AM +0100, Sam Jones wrote:
                                      >>
                                      >>> More to satisfy my own curiosity than anything else, I'm wondering about
                                      >>> the performance that could be squeezed out of Postfix in a bulk mailing
                                      >>> capacity.
                                      >> Running a high volume bulk email platform is not a software problem.
                                      >> It is a logistics problem. Enrolling on the whitelists and feedback
                                      >> loops of various large email providers, handling bounce-backs,
                                      >> jumping through rate-limit hoops, ...
                                      [...]
                                      >>
                                      >> I guess what I'm querying in a way is some of the sales blurb from
                                      >> people like PowerMTA & GreenArrow and the remarks they make about open
                                      >> source solutions like Postfix etc. This one in particular: "Open source
                                      >> Mail Transfer Agents (MTAs) often max out between 20 and 30 thousand
                                      >> messages per hour. GreenArrow can send 300,000 messages per hour—more
                                      >> than ten times as fast."
                                      >>

                                      Knowing absolutely nothing about the software mentioned - I would say
                                      there is a difference between messages SENT vs messages DELIVERED. I
                                      realize many will immediately correct me and say even Postfix can't
                                      guarantee delivery to a given recipient - merely acknowledgement of the
                                      recipient server's acceptance - but I don't know how else to
                                      discriminate between a single-pass of a message, without retries,
                                      without verification, without greylist tolerance, without reporting,
                                      just knock on the door and try to shove it on - vs reliable message
                                      handling.

                                      Again, knowing nothing about alternatives to Postfix - I question
                                      whether software intended for bulk mailing purposes is designed in such
                                      a manner. As a crude analogy, even the best machine gun doesn't have a
                                      fraction of the accuracy of a quality sniper rifle - but on the other
                                      hand a machine gun will put a lot more lead downrange. Different tools
                                      for different purposes. Spray-and-Pray - or deliver the personal message.

                                      --
                                      Daniel
                                    • fletch
                                      The postfix performance claims made via this thread are far-fetched to say the least. Most postfix users will only see outbound throughput in the range of
                                      Message 18 of 30 , Jun 12, 2013
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                                        The postfix performance claims made via this thread are far-fetched to say
                                        the least. Most postfix users will only see outbound throughput in the
                                        range of ~250,000/hour per instance in a production setting. Yet, people on
                                        here are claiming 10 million/hour? I guess that would be possible if a
                                        sender were to run, say, 40 postfix instances which would be a complete
                                        management nightmare of course.

                                        Obviously, vendors like Port25 (company behind PowerMTA) and GreenArrow
                                        would not be able to make any sales if the benefits of commercial software
                                        products v. open source were not substantial.



                                        --
                                        View this message in context: http://postfix.1071664.n5.nabble.com/Bulk-Mailing-Performance-tp50222p58873.html
                                        Sent from the Postfix Users mailing list archive at Nabble.com.
                                      • Wietse Venema
                                        ... Is this a troll? I have documented Postfix performance claims on Wikipedia. Be sure to read the cautionary note about factors outside of Postfix that in
                                        Message 19 of 30 , Jun 12, 2013
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                                          fletch:
                                          > The postfix performance claims made via this thread are far-fetched to say
                                          > the least. Most postfix users will only see outbound throughput in the
                                          > range of ~250,000/hour per instance in a production setting. Yet, people on
                                          > here are claiming 10 million/hour? I guess that would be possible if a
                                          > sender were to run, say, 40 postfix instances which would be a complete
                                          > management nightmare of course.
                                          >
                                          > Obviously, vendors like Port25 (company behind PowerMTA) and GreenArrow
                                          > would not be able to make any sales if the benefits of commercial software
                                          > products v. open source were not substantial.

                                          Is this a troll?

                                          I have documented Postfix performance claims on Wikipedia. Be sure
                                          to read the cautionary note about factors outside of Postfix that
                                          in practice limit the delivery performance.

                                          Wietse
                                        • Joe
                                          ... In our experience, postfix can blast out messages at rates which are orders of magnitude faster than the other end is willing to receive it. The
                                          Message 20 of 30 , Jun 12, 2013
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                                            On 06/12/2013 12:17 PM, fletch wrote:
                                            > The postfix performance claims made via this thread are far-fetched to say
                                            > the least. Most postfix users will only see outbound throughput in the
                                            > range of ~250,000/hour per instance in a production setting. Yet, people on
                                            > here are claiming 10 million/hour? I guess that would be possible if a
                                            > sender were to run, say, 40 postfix instances which would be a complete
                                            > management nightmare of course.
                                            >
                                            > Obviously, vendors like Port25 (company behind PowerMTA) and GreenArrow
                                            > would not be able to make any sales if the benefits of commercial software
                                            > products v. open source were not substantial.


                                            In our experience, postfix can blast out messages at rates which are
                                            orders of magnitude faster than the other end is willing to receive it.
                                            The "substantial benefits" you speak of are mainly along the lines of
                                            easier management tools and integration of same with various other email
                                            related components in one convenient interface.

                                            Joe
                                          • Peer Heinlein
                                            ... You already lost. I did this even 5-6 years ago with 3-4 millionen mails / hour in one postfix instance on one stupid dual-xeon server with 100 MBit
                                            Message 21 of 30 , Jun 12, 2013
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                                              Am 12.06.2013 21:17, schrieb fletch:

                                              > here are claiming 10 million/hour? I guess that would be possible if a
                                              > sender were to run, say, 40 postfix instances which would be a complete
                                              > management nightmare of course.

                                              You already lost.

                                              I did this even 5-6 years ago with 3-4 millionen mails / hour in one
                                              postfix instance on one stupid dual-xeon server with 100 MBit uplink.

                                              > Obviously, vendors like Port25 (company behind PowerMTA) and GreenArrow
                                              > would not be able to make any sales if the benefits of commercial software
                                              > products v. open source were not substantial.

                                              They're making sales with people, that believe that people coming from a
                                              comercial company are always and automatically better then everbody else.


                                              Peer


                                              --
                                              Heinlein Support GmbH
                                              Schwedter Str. 8/9b, 10119 Berlin

                                              http://www.heinlein-support.de

                                              Tel: 030 / 405051-42
                                              Fax: 030 / 405051-19

                                              Zwangsangaben lt. §35a GmbHG: HRB 93818 B / Amtsgericht
                                              Berlin-Charlottenburg,
                                              Geschäftsführer: Peer Heinlein -- Sitz: Berlin
                                            • Robert Schetterer
                                              ... however magic jedi software overpower setup you might use for deliver out, you never will reach the higher powered master level , where you can press all
                                              Message 22 of 30 , Jun 12, 2013
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                                                Am 12.06.2013 21:17, schrieb fletch:
                                                > The postfix performance claims made via this thread are far-fetched to say
                                                > the least. Most postfix users will only see outbound throughput in the
                                                > range of ~250,000/hour per instance in a production setting. Yet, people on
                                                > here are claiming 10 million/hour? I guess that would be possible if a
                                                > sender were to run, say, 40 postfix instances which would be a complete
                                                > management nightmare of course.
                                                >
                                                > Obviously, vendors like Port25 (company behind PowerMTA) and GreenArrow
                                                > would not be able to make any sales if the benefits of commercial software
                                                > products v. open source were not substantial.
                                                >
                                                >
                                                >
                                                > --
                                                > View this message in context: http://postfix.1071664.n5.nabble.com/Bulk-Mailing-Performance-tp50222p58873.html
                                                > Sent from the Postfix Users mailing list archive at Nabble.com.
                                                >

                                                however magic jedi software overpower setup you might use for deliver
                                                out, you never will reach the higher powered master level , where you
                                                can press all others to take your mails at a number in time periods you
                                                might like , so using paid services/software for bulk maybe a good idea
                                                by many things, comparing it to some default settings of postfix is
                                                simply nonsense and typical marketing bla bla


                                                Best Regards
                                                MfG Robert Schetterer

                                                --
                                                [*] sys4 AG

                                                http://sys4.de, +49 (89) 30 90 46 64
                                                Franziskanerstraße 15, 81669 München

                                                Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263
                                                Vorstand: Patrick Ben Koetter, Axel von der Ohe, Marc Schiffbauer
                                                Aufsichtsratsvorsitzender: Florian Kirstein
                                              • fletch
                                                Peer, There s no way that s a production figure. You may have queued that many, but I seriously doubt you got anything close to 3-4 million/hour when postfix
                                                Message 23 of 30 , Jun 12, 2013
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                                                  Peer,

                                                  There's no way that's a production figure. You may have queued that many,
                                                  but I seriously doubt you got anything close to 3-4 million/hour when
                                                  postfix was actually conducting delivery with the remote gateways...



                                                  On Wed, Jun 12, 2013 at 1:02 PM, Peer Heinlein [via Postfix] <
                                                  ml-node+s1071664n58876h85@...> wrote:

                                                  > Am 12.06.2013 21:17, schrieb fletch:
                                                  >
                                                  > > here are claiming 10 million/hour? I guess that would be possible if a
                                                  > > sender were to run, say, 40 postfix instances which would be a complete
                                                  > > management nightmare of course.
                                                  >
                                                  > You already lost.
                                                  >
                                                  > I did this even 5-6 years ago with 3-4 millionen mails / hour in one
                                                  > postfix instance on one stupid dual-xeon server with 100 MBit uplink.
                                                  >
                                                  > > Obviously, vendors like Port25 (company behind PowerMTA) and GreenArrow
                                                  > > would not be able to make any sales if the benefits of commercial
                                                  > software
                                                  > > products v. open source were not substantial.
                                                  >
                                                  > They're making sales with people, that believe that people coming from a
                                                  > comercial company are always and automatically better then everbody else.
                                                  >
                                                  >
                                                  > Peer
                                                  >
                                                  >
                                                  > --
                                                  > Heinlein Support GmbH
                                                  > Schwedter Str. 8/9b, 10119 Berlin
                                                  >
                                                  > http://www.heinlein-support.de
                                                  >
                                                  > Tel: 030 / 405051-42
                                                  > Fax: 030 / 405051-19
                                                  >
                                                  > Zwangsangaben lt. §35a GmbHG: HRB 93818 B / Amtsgericht
                                                  > Berlin-Charlottenburg,
                                                  > Geschäftsführer: Peer Heinlein -- Sitz: Berlin
                                                  >
                                                  >
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                                                • Ben Johnson
                                                  ... This point is somewhat moot, quite frankly, because the performance claims as documented on Wikipedia state: Postfix has been clocked at ~300 message
                                                  Message 24 of 30 , Jun 12, 2013
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                                                    On 6/12/2013 4:40 PM, fletch wrote:
                                                    > Peer,
                                                    >
                                                    > There's no way that's a production figure. You may have queued that many,
                                                    > but I seriously doubt you got anything close to 3-4 million/hour when
                                                    > postfix was actually conducting delivery with the remote gateways...
                                                    >

                                                    This point is somewhat moot, quite frankly, because the performance
                                                    claims as documented on Wikipedia state:

                                                    Postfix has been clocked at ~300 message deliveries/second[6] across the
                                                    Internet, running on commodity hardware (a vintage-2003 Dell 1850 system
                                                    with battery-backed MegaRAID controller and two SCSI disks). This
                                                    delivery rate is an order of magnitude below the "intrinsic" limit of
                                                    2500 message deliveries/second[6] that was achieved *with the mail queue
                                                    on a RAM disk while delivering to the "discard" transport (with a
                                                    dual-core Opteron system in 2007).*

                                                    Nobody (besides perhaps Peer) is making any claim with respect to
                                                    "real-world" performance. The performance claims as documented assume
                                                    factors only within Postfix and the computer on which it's runnings'
                                                    control.

                                                    -Ben
                                                  • AFCommerce LLC
                                                    I know powermta as well as postfix and I think I can add to some of the comments on here, powermta is not cheap by any means and of course postfix is free,
                                                    Message 25 of 30 , Jun 12, 2013
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                                                      I know powermta as well as postfix and I think I can add to some of the comments on here, powermta is not cheap by any means and of course postfix is free, however pmta might have some settings out of the box that are optimized for bulk but they can not come close to postfix as far as email standards go, incoming mail, etc (in my opinion) mainly from how many servers are using it, basically postfix, exim and sendmail create the standards that a company like pmta has to try to follow.

                                                      But the main reason bulk mailers mainly pay for pmta is because it has the ability to send on many ips/hostnames far easier than postfix, since postfix wasn't built (by choice) to send from 100s of ips and domains because that can easily become a tool for a spammer (a spammer could try to modify postfix I assume). The commercial support is a 2nd reason, most of us on this list wouldn't need that type of support, but a legitimate company who doesn't have a decent support staff would be interested in that.


                                                      On Wed, Jun 12, 2013 at 4:09 PM, Robert Schetterer <rs@...> wrote:
                                                      Am 12.06.2013 21:17, schrieb fletch:
                                                      > The postfix performance claims made via this thread are far-fetched to say
                                                      > the least.  Most postfix users will only see outbound throughput in the
                                                      > range of ~250,000/hour per instance in a production setting.  Yet, people on
                                                      > here are claiming 10 million/hour?  I guess that would be possible if a
                                                      > sender were to run, say, 40 postfix instances which would be a complete
                                                      > management nightmare of course.
                                                      >
                                                      > Obviously, vendors like Port25 (company behind PowerMTA) and GreenArrow
                                                      > would not be able to make any sales if the benefits of commercial software
                                                      > products v. open source were not substantial.
                                                      >
                                                      >
                                                      >
                                                      > --
                                                      > View this message in context: http://postfix.1071664.n5.nabble.com/Bulk-Mailing-Performance-tp50222p58873.html
                                                      > Sent from the Postfix Users mailing list archive at Nabble.com.
                                                      >

                                                      however magic jedi software overpower setup you might use for deliver
                                                      out, you never will reach the higher powered master level , where you
                                                      can press all others to take your mails at a number in time periods you
                                                      might like , so using paid services/software for bulk maybe a good idea
                                                      by many things, comparing it to some default settings of postfix is
                                                      simply nonsense and typical marketing bla bla


                                                      Best Regards
                                                      MfG Robert Schetterer

                                                      --
                                                      [*] sys4 AG

                                                      http://sys4.de, +49 (89) 30 90 46 64
                                                      Franziskanerstraße 15, 81669 München

                                                      Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263
                                                      Vorstand: Patrick Ben Koetter, Axel von der Ohe, Marc Schiffbauer
                                                      Aufsichtsratsvorsitzender: Florian Kirstein

                                                    • Roel Wagenaar
                                                      ... say ... people on ... software ... Obviously YES. And quite a lot of feeders too. ... DFTT -- Roel Wagenaar, Linux-User #469851 with the Linux Counter;
                                                      Message 26 of 30 , Jun 12, 2013
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                                                        wietse@... (Wietse Venema) wrote:

                                                        > fletch:
                                                        > > The postfix performance claims made via this thread are far-fetched to
                                                        say
                                                        > > the least. Most postfix users will only see outbound throughput in the
                                                        > > range of ~250,000/hour per instance in a production setting. Yet,
                                                        people on
                                                        > > here are claiming 10 million/hour? I guess that would be possible if a
                                                        > > sender were to run, say, 40 postfix instances which would be a complete
                                                        > > management nightmare of course.
                                                        > >
                                                        > > Obviously, vendors like Port25 (company behind PowerMTA) and GreenArrow
                                                        > > would not be able to make any sales if the benefits of commercial
                                                        software
                                                        > > products v. open source were not substantial.
                                                        >
                                                        > Is this a troll?



                                                        Obviously YES.


                                                        And quite a lot of feeders too.


                                                        > I have documented Postfix performance claims on Wikipedia. Be sure
                                                        > to read the cautionary note about factors outside of Postfix that
                                                        > in practice limit the delivery performance.
                                                        >
                                                        > Wietse
                                                        >
                                                        >

                                                        DFTT


                                                        --
                                                        Roel Wagenaar,

                                                        Linux-User #469851 with the Linux Counter; http://linuxcounter.net/

                                                        Antw.: Omdat het de volgorde verstoord waarin mensen tekst lezen.
                                                        Vraag: Waarom is top-posting een slechte gewoonte?
                                                        Antw.: Top-posting.
                                                        Vraag: Wat is het meest ergerlijke in e-mail?

                                                        Diplomacy is the art of letting someone else get your way.
                                                      • fletch
                                                        What do you mean by: ...they can not come close to postfix as far as email standards go ? My understanding is that powermta fully complies with the various
                                                        Message 27 of 30 , Jun 12, 2013
                                                        • 0 Attachment
                                                          What do you mean by: "...they can not come close to postfix as far as email
                                                          standards go"? My understanding is that powermta fully complies with the
                                                          various RFCs.

                                                          Also, I'm sure there are far more spammers using free software like postfix
                                                          rather than paying for a commercial product.


                                                          On Wed, Jun 12, 2013 at 1:57 PM, AFCommerce LLC [via Postfix] <
                                                          ml-node+s1071664n58880h9@...> wrote:

                                                          > I know powermta as well as postfix and I think I can add to some of the
                                                          > comments on here, powermta is not cheap by any means and of course postfix
                                                          > is free, however pmta might have some settings out of the box that are
                                                          > optimized for bulk but they can not come close to postfix as far as email
                                                          > standards go, incoming mail, etc (in my opinion) mainly from how many
                                                          > servers are using it, basically postfix, exim and sendmail create the
                                                          > standards that a company like pmta has to try to follow.
                                                          >
                                                          > But the main reason bulk mailers mainly pay for pmta is because it has the
                                                          > ability to send on many ips/hostnames far easier than postfix, since
                                                          > postfix wasn't built (by choice) to send from 100s of ips and domains
                                                          > because that can easily become a tool for a spammer (a spammer could try to
                                                          > modify postfix I assume). The commercial support is a 2nd reason, most of
                                                          > us on this list wouldn't need that type of support, but a legitimate
                                                          > company who doesn't have a decent support staff would be interested in that.
                                                          >
                                                          >
                                                          > On Wed, Jun 12, 2013 at 4:09 PM, Robert Schetterer <[hidden email]<http://user/SendEmail.jtp?type=node&node=58880&i=0>
                                                          > > wrote:
                                                          >
                                                          >> Am 12.06.2013 21:17, schrieb fletch:
                                                          >> > The postfix performance claims made via this thread are far-fetched to
                                                          >> say
                                                          >> > the least. Most postfix users will only see outbound throughput in the
                                                          >> > range of ~250,000/hour per instance in a production setting. Yet,
                                                          >> people on
                                                          >> > here are claiming 10 million/hour? I guess that would be possible if a
                                                          >> > sender were to run, say, 40 postfix instances which would be a complete
                                                          >> > management nightmare of course.
                                                          >> >
                                                          >> > Obviously, vendors like Port25 (company behind PowerMTA) and GreenArrow
                                                          >> > would not be able to make any sales if the benefits of commercial
                                                          >> software
                                                          >> > products v. open source were not substantial.
                                                          >> >
                                                          >> >
                                                          >> >
                                                          >> > --
                                                          >> > View this message in context:
                                                          >> http://postfix.1071664.n5.nabble.com/Bulk-Mailing-Performance-tp50222p58873.html
                                                          >> > Sent from the Postfix Users mailing list archive at Nabble.com.
                                                          >> >
                                                          >>
                                                          >> however magic jedi software overpower setup you might use for deliver
                                                          >> out, you never will reach the higher powered master level , where you
                                                          >> can press all others to take your mails at a number in time periods you
                                                          >> might like , so using paid services/software for bulk maybe a good idea
                                                          >> by many things, comparing it to some default settings of postfix is
                                                          >> simply nonsense and typical marketing bla bla
                                                          >>
                                                          >>
                                                          >> Best Regards
                                                          >> MfG Robert Schetterer
                                                          >>
                                                          >> --
                                                          >> [*] sys4 AG
                                                          >>
                                                          >> http://sys4.de, <a href="tel:%2B49%20%2889%29%2030%2090%2046%2064"
                                                          >> value="+498930904664">+49 (89) 30 90 46 64
                                                          >> Franziskanerstraße 15, 81669 München
                                                          >>
                                                          >> Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263
                                                          >> Vorstand: Patrick Ben Koetter, Axel von der Ohe, Marc Schiffbauer
                                                          >> Aufsichtsratsvorsitzender: Florian Kirstein
                                                          >>
                                                          >
                                                          >
                                                          >
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                                                        • Viktor Dukhovni
                                                          ... Let s not go down this rabbit-hole. At this point in the thread we re no longer talking about Postfix. -- Viktor.
                                                          Message 28 of 30 , Jun 12, 2013
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                                                            On Wed, Jun 12, 2013 at 03:53:17PM -0700, fletch wrote:

                                                            > What do you mean by: "...they can not come close to postfix as far as email
                                                            > standards go"? My understanding is that powermta fully complies with the
                                                            > various RFCs.
                                                            >
                                                            > Also, I'm sure there are far more spammers using free software like postfix
                                                            > rather than paying for a commercial product.

                                                            Let's not go down this rabbit-hole. At this point in the thread we're no
                                                            longer talking about Postfix.

                                                            --
                                                            Viktor.
                                                          • Marius Gologan
                                                            Bulk doesn t mean to blast the world in 1 second with emails. 1) The magic of PowerMTA consists in rotating IPs base on returned codes and returned message
                                                            Message 29 of 30 , Jun 30, 2013
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                                                              Bulk doesn't mean to blast the world in 1 second with emails.


                                                              1) The magic of PowerMTA consists in rotating IPs base on returned codes and
                                                              returned message patterns. e.g.: if an IP addresses is banned by an ESP,
                                                              will backoff on a different IP address in order in an attempt to achieve
                                                              delivery. Thus, is designed for email marketing area, not for corporate
                                                              email service.
                                                              If you read the 330 pages guide you'll find that, by default, is sending 2
                                                              messages via 2 parallel connections. Can be increased considerable, but you
                                                              need to be a genius in 'warp speed' throttling and have IPs+Sender Domains
                                                              as Amazon SES has.
                                                              It is very limited for inbound messages handling.

                                                              2) Postfix is a true performance MTA, used world wide (mature).
                                                              The Magic of Postfix is quite complex. E.g: unlike PowerMTA, provides
                                                              dynamic/adaptive throttling which is quite intelligent. It looks like it
                                                              doesn't provide a way for rotating IPs as PowerMTA does. Thus, I don't see
                                                              how spammers prefer Postfix. I'm still learning about Postfix secrets and
                                                              how much creative can be.
                                                              In my opinion, the performance for bulk deliverability should be reduce in
                                                              Postfix, not increased, in order to meat ESP requirements in these days.

                                                              Both MTAs are designed for two different purposes, thus, you cannot compare
                                                              them.

                                                              Postfix, on a *nix machine, is a true Email Server - a complex platform with
                                                              many features, covering all aspects and requirements you can imagine (except
                                                              the one mentioned above), but, often, many steps ahead MS Exchange.
                                                              PowerMTA is an advanced sending software application for email marketers,
                                                              covering exclusively their requirements and needs of rotating IPs per ESP.

                                                              Marius.



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