Thread: gcwsieve
View Single Post
Old 2007-06-18, 22:40   #21
geoff's Avatar
Mar 2003
New Zealand

13×89 Posts
Default gcwsieve 1.0.9

Some changes to the 32-bit SSE2 assembler (taken from sr5sieve 1.5.6) have had a big effect on P4 performance. Here are some times for my 2.9 GHz P4 at p=4200e9 using the 2947 term sieve file for the 2.5-5.0 million n range:
Version  Single Thread      2 Hyperthreads
-------  -------------      --------------
1.0.7:   405 kp/s           700 kp/s
1.0.8:   446 kp/s (+10%)    720 kp/s (+3%)
1.0.9:   644 kp/s (+44%)    786 kp/s (+9%)
I don't know whether other SSE2 machines will benefit by as much, or at all.

My P4 is still better off LLR testing, but my P4/Celeron would now be more productive sieving, even just on the 2.5-5 million range. (It is the same speed as a full P4 for sieving, but only half speed for LLR testing which it is doing at the moment).
geoff is offline