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-   -   Archived sieve reservations and discussions (https://www.mersenneforum.org/showthread.php?t=13389)

Oddball 2010-08-07 15:53

[quote]My new computer allowed me to squeeze in one more completed range before I go on vacation.
[/quote]
Well, I got to squeeze in yet another range. This computer rocks!
490T-495T complete, about 11200 factors found:

[URL]http://www.sendspace.com/file/dwsnad[/URL]

My flight leaves in just a couple of hours, so this will really be the last range I finish before going on vacation.

mdettweiler 2010-08-07 16:00

480T-485T (range 1) complete, 11592 factors: [url]http://www.sendspace.com/file/vche0n[/url] (Lennart's site is acting a little strangely ATM.)

Reserving 495T-500T.

BTW @Oddball: I'm not sure if you'll get this before departing, but did you by chance run a comparison to see which is faster overall, one 6-threaded instance of tpsieve or 6 one-threaded instances? In my experience, even the best of multithreaded applications suffers a little performance hit as it scales across multiple cores; I'm curious to see how pronounced that effect is with 6 threads.

henryzz 2010-08-08 14:33

[quote=mdettweiler;224391]480T-485T (range 1) complete, 11592 factors: [URL]http://www.sendspace.com/file/vche0n[/URL] (Lennart's site is acting a little strangely ATM.)

Reserving 495T-500T.

BTW @Oddball: I'm not sure if you'll get this before departing, but did you by chance run a comparison to see which is faster overall, one 6-threaded instance of tpsieve or 6 one-threaded instances? In my experience, even the best of multithreaded applications suffers a little performance hit as it scales across multiple cores; I'm curious to see how pronounced that effect is with 6 threads.[/quote]
From memory tpsieve is a memory hog. He probably doesn't have enough memory to run 6x1Gb jobs

mdettweiler 2010-08-08 17:48

[quote=henryzz;224451]From memory tpsieve is a memory hog. He probably doesn't have enough memory to run 6x1Gb jobs[/quote]
Hmm, hadn't thought of that. I suppose 2 instances with 3 threads apiece would work pretty well, though--depending on how tpsieve scales (the only other comparison point I have is Prime95, which does a radically different type of calculation; it scales badly for >4 threads), that may do the trick to recover a lot of performance loss.

Puzzle-Peter 2010-08-10 17:17

When I was sieving for n=333333 I got the best performance by running -t2 sieves which was as fast as two single threads but less administration. Two times -t2 on a quad, four times on a V8. More threads per sieve were inefficient even when I did not reach memory limits.

BTW: which is the most recent release for Linux64? Maby newer version behave differently...

mdettweiler 2010-08-11 10:59

495T-500T complete, 11300 factors: [url]http://www.sendspace.com/file/1mgk1w[/url]

Will return after the impending NPLB rally. :smile:

Oddball 2010-08-13 01:47

[quote=Oddball;223885]I'll be away too for a while. My vacation's a bit shorter - from August 7th until the 12th.[/quote]
I'm back :smile:
Reserving 500T-510T.

[quote]
Is now Moomoo2=MooooMoo ?[/quote]
Probably not, the name seems to be a Pokemon reference and nothing more. In that game, MooMoo milk was an item used to heal Pokemon. It came from a Pokemon called Miltank, which also happens to be MooMoo2's avatar. As for the number 2 in MooMoo2's username, I'm guessing that it's there because Miltank first appeared in the 2nd generation of Pokemon.

Anyway, I'm not merging the MooMoo2 and the MooooMoo names in the stats page. MooMoo2 =/= MooooMoo unless proven otherwise.

[quote]
I'm not sure if you'll get this before departing, but did you by chance run a comparison to see which is faster overall, one 6-threaded instance of tpsieve or 6 one-threaded instances? In my experience, even the best of multithreaded applications suffers a little performance hit as it scales across multiple cores; I'm curious to see how pronounced that effect is with 6 threads.[/quote]
[quote]From memory tpsieve is a memory hog. He probably doesn't have enough memory to run 6x1Gb jobs[/quote]
I have 8GB of RAM, which is barely enough to fit 6 X 1GB threads (Windows 7 takes up nearly one and a half gigs of RAM). Here were the results:

one 2-threaded instance of tpsieve: 33.1 M p/sec
two 1-threaded instances of tpsieve: 33.3 M p/sec

one 6-threaded instance of tpsieve: 85.2 M p/sec
six 1-threaded instances of tpsieve: 84.9 M p/sec

The performance hit/gain seems to be negligible for tpsieve.

[quote]
495T-500T complete[/quote]
That finishes a major milestone - the work done since last year is equivalent to sieving n=480K-495K until p=500T (the 480K-485K range is missing 200T-300T, but this is balanced out by the 485K-495K range, which is completed to 550T). Let's see whether we can reach 1P by the end of next month.

Thanks to everyone who participated!

amphoria 2010-08-13 08:28

Reserving 510T-515T (range 1).

Oddball 2010-08-14 17:20

500T-510T complete, about 22100 factors found:

[URL]http://www.sendspace.com/file/bh3z6d[/URL]

Reserving 515T-525T.

gribozavr 2010-08-15 10:58

I'm back. I've downloaded and verified all files from posts above.

Oddball: Unfortunately, it was (is?) extremely hot here and we had problems with electricity. Range 200T-300T should have been completed, but it is not, I'm now continuing it (32% done). The machine that was processing 550T-750T is a remote one and it is still down. I don't know how much of 550T-750T is done, so in order not to duplicate work, I'll be waiting until the machine is fixed.

Oddball 2010-08-15 18:23

515T-525T complete, about 21300 factors found:

[URL]http://www.sendspace.com/file/8mbks2[/URL]

I'll get 525T-550T.

[quote=gribozavr;225500]
Oddball: Unfortunately, it was (is?) extremely hot here and we had problems with electricity. Range 200T-300T should have been completed, but it is not, I'm now continuing it (32% done). The machine that was processing 550T-750T is a remote one and it is still down. I don't know how much of 550T-750T is done, so in order not to duplicate work, I'll be waiting until the machine is fixed.[/quote]
I see. When you're done with the 200T-300T range, could you upload the 480K-485K file as well as the small k file (k<100000 for n=480K-481K)? I might try some LLR work for a change.


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