--- In

primenumbers@yahoogroups.com, Phil Carmody <thefatphil@...> wrote:

>

> Jack Brennen wrote:

> > Looks like you can extrapolate that implementation to get the first

> > 3.2 trillion primes in about 5-6 hours on an Intel i7-920, assuming

> > sufficient RAM available.

>

> I think the results of a willy-waving contest nearly a decade ago between Terje Mathisen and James Van Buskirk on c.l.a.x, concluded that about an order of magnitude faster than that speed should be possible. If you're James, that is. Tomas e Silva's sieve uses pretty much the same algorithm, but he hasn't optimised it quite as much. (James is an extreme optimiser, very few people can optimise as much!)

> http://www.ieeta.pt/~tos/software/prime_sieve.html

>

> Phil

>

Nearly two orders of magnitude is possible. YAFU and primesieve both compute pi(x) to 3.2e12 using the sieve of Eratosthenes in about 30 minutes on my machine (a pretty fast server). They are both threadable too - with 4 threads YAFU takes about 8 minutes.

- ben.