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Old 2009-01-07, 20:16   #23
henryzz
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Quote:
Originally Posted by engracio View Post
Hey guys need a liltle help on Ubuntu 8.10 Ibex x64. I am not able to run sr2sieve on this box. When I type in or cut and paste " sr2sieve -i dual_s.abcd -p 29e12 -P 30e12 " I get command not found. I made sure that sr2sieve is executable.

Since this box is dual booted with XP32 sp3, I tried it on xp and it was able to run sr2sieve. I am using the correct files for each os. Windows on xp and linux on x64. Any areas I need to check or change. thanks.
you need to type ./ before the command in linux
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Old 2009-01-07, 20:34   #24
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Quote:
Originally Posted by henryzz View Post
you need to type ./ before the command in linux

Dooh!!! I do it on all other linux dc client so why not sr2sieve.

Thanks that is all it needed.
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Old 2009-01-08, 02:14   #25
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On my Core 2 Duo machine (32Kb L1 cache) I noticed that sr2sieve was not choosing the best hashtable size by default for the current (5 k) sieve file. Adding the -H16 switch to the command line causes it to use a 16Kb instead of 32Kb hashtable, and sieving speed increased from 3.25M p/sec to 3.48M p/sec.

Once Ben's PRP (k=75353) is removed from the sieve file the smaller hashtable should be chosen by default.

The best hashtable size will be different on different hardware, so if you want to squeeze a little more speed out of the sieve you can try using the -H switch to select a size either half or double the default size and see if the speed increases. Use the -v switch to see what size is chosen by default.
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Old 2009-01-08, 04:33   #26
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Quote:
Originally Posted by geoff View Post
On my Core 2 Duo machine (32Kb L1 cache) I noticed that sr2sieve was not choosing the best hashtable size by default for the current (5 k) sieve file. Adding the -H16 switch to the command line causes it to use a 16Kb instead of 32Kb hashtable, and sieving speed increased from 3.25M p/sec to 3.48M p/sec.

Once Ben's PRP (k=75353) is removed from the sieve file the smaller hashtable should be chosen by default.

The best hashtable size will be different on different hardware, so if you want to squeeze a little more speed out of the sieve you can try using the -H switch to select a size either half or double the default size and see if the speed increases. Use the -v switch to see what size is chosen by default.
Thanks geoff, my q8200 ubuntu x64 jump from 1219xxxx to1293xxxx p/sec soon as I added the switch. Any speed increase is a plus.
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Old 2009-01-08, 09:52   #27
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a lot of core 2s have two parts of their L1 cache
Level 1 cache size
4 x 32 KB instruction caches
4 x 32 KB data caches


also sr1sieve(probably sr2sieve as well but i havent used it) detects my L2 cache size as 4MB even though that 4MB is divided between two cores
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Old 2009-01-08, 17:37   #28
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The new 4 k sieve file was uploaded this morning - sorry about the glitch yesterday! The new file has 600731 entries. You can stop sr2sieve, download the new file, and restart the program from the checkpoint. If anyone has interesting observations about the sieve speed-up, please post them here.
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Old 2009-01-09, 00:59   #29
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I notice that the new sieve file is named dual_s.abcd, while the old sieve file was named dualSierp.abcd, so you will want to enter your command line differently when you sieve, for example:

sr2sieve -i dual_s.abcd -p 24e12 -P 25e12
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Old 2009-01-09, 03:47   #30
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Quote:
Originally Posted by engracio View Post
Dooh!!! I do it on all other linux dc client so why not sr2sieve.

Thanks that is all it needed.
The simple, permanent solution to this problem is to add "./" to your path. If you're running csh, for example, you would put this into your .cshrc file:

setenv PATH ./:$PATH

For Bourne shell, the equivalent is:

export PATH=./:$PATH
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Old 2009-01-09, 03:56   #31
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That is a potentially dangerous thing to do.
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Old 2009-01-09, 04:48   #32
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Quote:
Originally Posted by philmoore View Post
The new 4 k sieve file was uploaded this morning - sorry about the glitch yesterday! The new file has 600731 entries. You can stop sr2sieve, download the new file, and restart the program from the checkpoint. If anyone has interesting observations about the sieve speed-up, please post them here.
Phil,

When I was finally able to get the new .dat with just 4k, the speed jumped from 1256xxxx to 1436xxxx. p/sec on my q8200.

Nice benefit getting rid of that 75353 k.
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Old 2009-01-09, 12:05   #33
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I had a nice speed boost as well, my Q6600 went from 1,600,000 p/sec to almost 2,000,000 p/sec on the 32 bit version.
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