mersenneforum.org  

Go Back   mersenneforum.org > Factoring Projects > Msieve

Reply
 
Thread Tools
Old 2020-03-10, 18:07   #12
VBCurtis
 
VBCurtis's Avatar
 
"Curtis"
Feb 2005
Riverside, CA

33·5·31 Posts
Default

Xyzzy-
While unlikely, it is possible that 20 or 24 threads yields a bit of improvement. Hyperthreads don't always help on matrix solving, but since this is a benchmark thread it might be nice to demonstrate that.

I suggest 20 as alternative because using every possible HT might be impacted by any background process, but that effect should be reduced if we leave a few HTs 'open'. I've found situations where using N-1 cores runs faster than N cores, for what I presume are similar reasons.
VBCurtis is offline   Reply With Quote
Old 2020-03-10, 18:17   #13
pinhodecarlos
 
pinhodecarlos's Avatar
 
"Carlos Pinho"
Oct 2011
Milton Keynes, UK

23·571 Posts
Default

HT helps a lot on LA, at least for me.
pinhodecarlos is offline   Reply With Quote
Old 2020-03-12, 23:36   #14
VBCurtis
 
VBCurtis's Avatar
 
"Curtis"
Feb 2005
Riverside, CA

33·5·31 Posts
Default

Quote:
Originally Posted by VBCurtis View Post
-nc1 was run with target-density 134. After remdups and adding freerels in, msieve states 99.3M unique relations. Matrix came out 4.57M dimensions. TD=140 did not complete filtering.
Machine: Xeon 2680v3 Haswell generation 12x2.5ghz, 48GB memory on 4 channels DDR4 (4x4GB+4x8GB).

VBITS=128 on otherwise idle machine. ETA after 1% of job:
6-threaded 14hr 34 min
12-threads 8 hr 26 min
18-threads 9 hr 15 min
24-threads 8 hr 27 min
These times look rather slow; I just installed the extra 32GB memory today, so perhaps filling all 8 slots slows memory access a bunch. Some time I'll remove the original 16GB and see if 4 sticks is faster than 8.
VBCurtis is offline   Reply With Quote
Old 2020-04-27, 12:16   #15
Xyzzy
 
Xyzzy's Avatar
 
"Mike"
Aug 2002

7×29×37 Posts
Default

Quote:
Originally Posted by VBCurtis View Post
While unlikely, it is possible that 20 or 24 threads yields a bit of improvement. Hyperthreads don't always help on matrix solving, but since this is a benchmark thread it might be nice to demonstrate that.

I suggest 20 as alternative because using every possible HT might be impacted by any background process, but that effect should be reduced if we leave a few HTs 'open'. I've found situations where using N-1 cores runs faster than N cores, for what I presume are similar reasons.
We ran a 24 thread test last night. It was 1.09% faster than the 12 thread job. During the run, the CPU reported roughly 1700% utilization, so there must be a lot of overhead and/or bottlenecks. We are currently running a 20 thread test that we will post later.

Note that we only count the LA phase in our calculations.

Attached Files
File Type: log 24.log (11.5 KB, 12 views)
Xyzzy is offline   Reply With Quote
Old 2020-04-27, 22:12   #16
Xyzzy
 
Xyzzy's Avatar
 
"Mike"
Aug 2002

7×29×37 Posts
Default

Quote:
Originally Posted by Xyzzy View Post
We are currently running a 20 thread test that we will post later.
The 20 thread run somehow ended up slower than the 12 thread run.

12 = 8h04m50s
20 = 8h32m31s
24 = 7h59m33s

Attached Files
File Type: log 20.log (10.5 KB, 9 views)
Xyzzy is offline   Reply With Quote
Reply

Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
PFGW benchmarking carpetpool Hardware 4 2019-09-30 20:06
Looking for benchmarking help with a Phenom or PhenomII X6 mrolle Software 25 2012-03-14 14:15
GMP 5.0.1 vs GMP 4.1.4 benchmarking unconnected GMP-ECM 5 2011-04-03 16:16
Benchmarking dual-CPU machines garo Software 2 2010-09-27 20:33
Benchmarking challenge! Xyzzy Software 17 2003-08-26 15:43

All times are UTC. The time now is 13:59.

Sun May 31 13:59:02 UTC 2020 up 67 days, 11:32, 1 user, load averages: 1.19, 1.30, 1.36

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.

This forum has received and complied with 0 (zero) government requests for information.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation.
A copy of the license is included in the FAQ.