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2010-05-12, 00:21   #23
Historian

Mar 2010

538 Posts

Quote:
 Originally Posted by gribozavr Yes, I'm working on 10G-150G, currently @ 46T. tpsieve needs 2.7 Gb of RAM. I started working on it when nobody talked about continuing previous search. Not much CPU time spent (a few days), so I can cancel it altogether if we decide that it is useless.
No, it's not useless; in fact I was thinking of picking up another range to LLR for this n. With that said, could you upload the sieve file for k<15M?

Last fiddled with by Historian on 2010-05-12 at 00:22

2010-05-12, 00:25   #24
gribozavr

Mar 2005
Internet; Ukraine, Kiev

11·37 Posts

Quote:
 Originally Posted by Lennart How does your tpconfig looks like ?
qmax=10e6 is not commented out. Everything else is the same.

Quote:
 Originally Posted by Historian No, it's not useless; in fact I was thinking of picking up another range to LLR for this n. With that said, could you upload the sieve file for k<15M?
Too early for LLR. Currently sieving removes tens of factors per second.

Last fiddled with by gribozavr on 2010-05-12 at 00:26

2010-05-12, 00:29   #25
Lennart

"Lennart"
Jun 2007

112010 Posts

Quote:
 Originally Posted by gribozavr qmax=10e6 is not commented out. Everything else is the same.
Ok. I run 2 tpsieve on my i7 920 both -t4 and I use ~85% cpu.

If I run -t8 it will go down to 70%.

Try raise nice.
priority=low to normal or 0

2010-05-12, 01:17   #26
TimSorbet
Account Deleted

"Tim Sorbera"
Aug 2006
San Antonio, TX USA

10B716 Posts

Quote:
 Originally Posted by gribozavr While we are talking about it, I want to ask a question. I've got a 4-core i5-750 and I start tpsieve with "-t 4". But top shows that it uses only 50% available time of each core. Why? RAM bandwidth is not enough?
Obvious question: Are you running any other math projects (or other programs) at the same priority that are taking the other half? Or is it actually idling?
Code:
# Sieve block size, in bytes. Should not exceed L2 cache size.
blocksize=512k
The L2 cache on my i5-750 is 4x256 KBytes (according to CPU-Z). Maybe your blocksize is too large to fit in your L2. Try setting blocksize to 256k or other values.
(I have blocksize set to 256k. When I run tpsieve with 4 threads it can use the equivalent of about 3.6 cores. I might be able to get this higher if I experimented more, but it's already certainly better than your performance of ~2.0 cores. blocksize is the most significant difference I have to your file that could be causing this. Another possibility is the priority, as Lennart suggested.)

Last fiddled with by TimSorbet on 2010-05-12 at 01:28

 2010-05-22, 08:10 #27 rajula     "Tapio Rajala" Feb 2010 Finland 32·5·7 Posts I would like to work also on this project (at least for a while) and reserve 2.0M - 3.0M. I'll run it on one core so it should be done in about two days.
2010-05-22, 19:20   #28
Oddball

May 2010

499 Posts

Quote:
 Originally Posted by rajula I would like to work also on this project (at least for a while) and reserve 2.0M - 3.0M. I'll run it on one core so it should be done in about two days.

Welcome to the twin search, and happy prime hunting

 2010-05-22, 19:45 #29 Lennart     "Lennart" Jun 2007 100011000002 Posts I shall do a test. I reserve 3M-10M Lennart
2010-05-22, 21:07   #30
TimSorbet
Account Deleted

"Tim Sorbera"
Aug 2006
San Antonio, TX USA

11·389 Posts

Quote:
 Originally Posted by Oddball Stats: Code: Rank Username Amount sieved (in M) 1 Oddball 1.3 2 Mini-Geek 0.5 3 Historian 0.2
This isn't sieving. It's primality testing. You could replace "sieved" with "tested" or "LLRed" or "LLRd" or something like that.

Last fiddled with by TimSorbet on 2010-05-22 at 21:10

2010-05-22, 21:15   #31
Oddball

May 2010

1F316 Posts

Quote:
 Originally Posted by Mini-Geek This isn't sieving. It's primality testing.
Oops Fixed.

I'll reserve 10M-12M.

 2010-05-22, 23:13 #32 Lennart     "Lennart" Jun 2007 46016 Posts Taking 12M-20M Lennart

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