internet draft on suggested mod to the Nagle algorithm
- Tcp-impl people,
Just in case you didn't see the following, i'm forwarding the announcement
along. I'd love to hear any thoughts people might have, both on the concept
and on how to implement it. (I need to do at least one modification to add in
how Sam Manthorpe/SGI has addressed this issue.)
Thanks, Greg Minshall
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To: IETF-Announce: ;
Subject: I-D ACTION:draft-minshall-nagle-00.txt
Date: Mon, 01 Feb 1999 11:53:39 -0500
A New Internet-Draft is available from the on-line Internet-Drafts directories.
Title : A Suggested Modification to Nagle's Algorithm
Author(s) : G. Minshall
Filename : draft-minshall-nagle-00.txt
Pages : 4
Date : 29-Jan-99
The Nagle algorithm is one of the primary mechanisms which protects
the internet from poorly designed and/or implemented applications.
However, for a certain class of applications (notably,
request-response protocols) the Nagle algorithm interacts poorly
with delayed acknowledgements to give these applications poorer
This draft is NOT suggesting that these applications should disable
the Nagle algorithm.
This draft suggests a fairly small and simple modification to the
Nagle algorithm to preserve Nagle as a means of protecting the
internet while at the same time giving better performance to a
wider class of applications.
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>> What's the difference [on the wire] between a flush bit in theNone that I can see.
>> send() system call, and explicit setsockopt()'s turning off
>> TCP_NODELAY off before a send() and on afterwards?
> The problem is that there isn't really a required correlation betweenThat's not how I read it. Suppose there is no send window available,
> send() calls and segments, regardless of NODELAY (or anything else I
> can find, excepting _only_ the proposed flush bit, which might be
> defined as guaranteeing that the last byte of the write is the last
> byte of a segment).
MSS 1500, 500 bytes buffered waiting for window, and then, without any
network traffic occurring during it, the application does
write-with-flush 10 bytes then ordinary write 10 bytes more. I don't
think any of the flush-bit proposals would require the next segment to
hold 510 bytes rather than 520 (assuming that when the window opens, it
opens at least 520 bytes' worth).
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