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Old 2020-11-23, 16:40   #34
VBCurtis
 
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At the command line: taskset -c 0-5 ./sllr64 -d

That instance of llr is bound to those 6 cores.
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Old 2020-11-24, 01:14   #35
diep
 
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Quote:
Originally Posted by axn View Post
You can start a command using taskset, not just set the affinity of existing process.
Now that is interesting!

That solves the problem right away!!

<PRE>
nohup taskset -c 0x00000003f /home/diep/89/sllr64 &
</PRE>
And then hope it works :)
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Old 2020-11-24, 01:19   #36
diep
 
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Quote:
Originally Posted by VBCurtis View Post
At the command line: taskset -c 0-5 ./sllr64 -d

That instance of llr is bound to those 6 cores.
Ah yes -c much better than the mask as easier to read.
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Old 2020-12-18, 02:48   #37
diep
 
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Ok testing here at the Xeons i notice with LLR that if an exponent has a problem that it probably is doing something else then slowing it down. Now that's ok if 1 exponent has a problem that for this specific exponent it happens - but it keeps getting the slow times then for the next series of exponents in the list.

Note all at 2 cores Xeon L5420.
See below - from systematically "scoring" 16k-17k+ second timings then systematically all timings get 24k - 27k+ seconds.

How to avoid this?

See below timings - note i also internet on this box and on this type Xeon box even if it would be idle it still isn't very consequent in timings i see on other machines there yet it's about the big picture here:

32767*2^4101473-1 is not prime. LLR Res64: FA84A1769FE24283 Time : 16897.779 sec.
32767*2^4103009-1 is not prime. LLR Res64: 8DF9BDCF88466FAE Time : 17090.899 sec.
32767*2^4104225-1 is not prime. LLR Res64: A57D26F36D87D892 Time : 16802.392 sec.
32767*2^4104465-1 is not prime. LLR Res64: D8786A3A79D3F359 Time : 18200.538 sec.
32767*2^4106945-1 is not prime. LLR Res64: 8DC7CCAEEA11FE48 Time : 17942.759 sec.
32767*2^4107825-1 is not prime. LLR Res64: 512A78D3A50DEA3F Time : 16107.209 sec.
32767*2^4109921-1 is not prime. LLR Res64: 31FC76F271FF0120 Time : 16164.177 sec.
32767*2^4111073-1 is not prime. LLR Res64: 9327513915719938 Time : 17099.554 sec.
32767*2^4111553-1 is not prime. LLR Res64: 4AC78A05671C7556 Time : 17602.927 sec.
32767*2^4112289-1 is not prime. LLR Res64: 26837D8FF89C6CC7 Time : 16750.925 sec.
32767*2^4114353-1 is not prime. LLR Res64: FF48F58E0FF7B865 Time : 16347.888 sec.
32767*2^4116321-1 is not prime. LLR Res64: 99B52F6824755635 Time : 17379.061 sec.
32767*2^4117425-1 is not prime. LLR Res64: 0856BBAD04389318 Time : 18949.598 sec.
32767*2^4118273-1 is not prime. LLR Res64: 8F81BE9803270946 Time : 18013.186 sec.
32767*2^4119905-1 is not prime. LLR Res64: 9A1C90E9408A0F21 Time : 16455.584 sec.
32767*2^4121169-1 is not prime. LLR Res64: 6BA8B79D26B6C400 Time : 14965.595 sec.
32767*2^4122081-1 is not prime. LLR Res64: 15C6767CB702988E Time : 16362.165 sec.
32767*2^4122801-1 is not prime. LLR Res64: 8D07CCBC76F458CB Time : 17121.588 sec.
32767*2^4124193-1 is not prime. LLR Res64: B481A62B2912F64A Time : 18505.062 sec.
32767*2^4126193-1 is not prime. LLR Res64: 97B82BC551F3FFD3 Time : 18709.559 sec.
32767*2^4128545-1 is not prime. LLR Res64: 77173DC87468D5A2 Time : 17801.900 sec.
32767*2^4128993-1 is not prime. LLR Res64: 6ACB065E32A13ED9 Time : 17728.279 sec.
32767*2^4130241-1 is not prime. LLR Res64: 200F8DF827962EDB Time : 16690.141 sec.
32767*2^4131345-1 is not prime. LLR Res64: FCC3BE70195E5D03 Time : 16470.305 sec.
32767*2^4132353-1 is not prime. LLR Res64: 52ED3CD5051BE971 Time : 18351.335 sec.
32767*2^4133681-1 is not prime. LLR Res64: 962E89938EC018A2 Time : 16284.558 sec.
32767*2^4134833-1 is not prime. LLR Res64: 2902BB84273B1029 Time : 14830.133 sec.
32767*2^4135953-1 is not prime. LLR Res64: C19F65BFDC4F7FE1 Time : 19130.523 sec.
32767*2^4137713-1 is not prime. LLR Res64: BB396569E706C14B Time : 19081.886 sec.
32767*2^4139313-1 is not prime. LLR Res64: 29B1921AF09C7FB5 Time : 16209.595 sec.
32767*2^4141073-1 is not prime. LLR Res64: 08B3AEE43099FB00 Time : 14897.605 sec.
32767*2^4142193-1 is not prime. LLR Res64: 66A0E82DAA189406 Time : 18802.833 sec.
32767*2^4143201-1 is not prime. LLR Res64: 05122F46F5BA879D Time : 18212.873 sec.
32767*2^4143969-1 is not prime. LLR Res64: CC278E4AA00CD709 Time : 17270.017 sec.
32767*2^4145553-1 is not prime. LLR Res64: 5F11E24E9CB440D2 Time : 16466.316 sec.
32767*2^4146689-1 is not prime. LLR Res64: 99CF3AB56045AB25 Time : 16852.775 sec.
32767*2^4147953-1 is not prime. LLR Res64: BAA226B247A6E76A Time : 14965.353 sec.
32767*2^4149233-1 is not prime. LLR Res64: EEB892D8D87E0D61 Time : 13072.448 sec.
32767*2^4150241-1 is not prime. LLR Res64: 65B3BF50D94E6A58 Time : 17524.087 sec.
Iter: 647351/4152080, ERROR: ROUND OFF (0.4375) > 0.4
Continuing from last save file.
Resuming LLR test of 32767*2^4152081-1 at iteration 444545 [10.70%]
32767*2^4152081-1 is not prime. LLR Res64: 08DF76A5E56313D7 Time : 17152.113 sec.
32767*2^4153841-1 is not prime. LLR Res64: 1F91AF5AD58C7E66 Time : 13279.942 sec.
32767*2^4155329-1 is not prime. LLR Res64: 7B15C93BFDA13457 Time : 19910.129 sec.
32767*2^4156785-1 is not prime. LLR Res64: 75617A13366D4CD9 Time : 16451.425 sec.
32767*2^4158369-1 is not prime. LLR Res64: 74EE925FE9755400 Time : 17554.074 sec.
Iter: 2093818/4159648, ERROR: ROUND OFF (0.4375) > 0.4
Continuing from last save file.
Resuming LLR test of 32767*2^4159649-1 at iteration 1761025 [42.33%]
Disregard last error. Result is reproducible and thus not a hardware problem.
For added safety, redoing iteration using a slower, more reliable method.
Continuing from last save file.
Resuming LLR test of 32767*2^4159649-1 at iteration 2093818 [50.33%]
32767*2^4159649-1 is not prime. LLR Res64: FA888797604FF91F Time : 19187.604 sec.
32767*2^4162385-1 is not prime. LLR Res64: 29F1B26E74408FE4 Time : 26793.191 sec.
32767*2^4162785-1 is not prime. LLR Res64: EC706F392A94CB6B Time : 20967.189 sec.
Iter: 1634141/4163392, ERROR: ROUND OFF (0.40625) > 0.4
Continuing from last save file.
Resuming LLR test of 32767*2^4163393-1 at iteration 1357825 [32.61%]
Disregard last error. Result is reproducible and thus not a hardware problem.
For added safety, redoing iteration using a slower, more reliable method.
Continuing from last save file.
Resuming LLR test of 32767*2^4163393-1 at iteration 1634141 [39.25%]
32767*2^4163393-1 is not prime. LLR Res64: FBDB37EC6CB9F80D Time : 22611.094 sec.
32767*2^4164689-1 is not prime. LLR Res64: 46337F8E6904FA71 Time : 22375.340 sec.
Iter: 3233274/4166144, ERROR: ROUND OFF (0.4375) > 0.4
Continuing from last save file.
Resuming LLR test of 32767*2^4166145-1 at iteration 3213697 [77.13%]
Disregard last error. Result is reproducible and thus not a hardware problem.
For added safety, redoing iteration using a slower, more reliable method.
Continuing from last save file.
Resuming LLR test of 32767*2^4166145-1 at iteration 3233274 [77.60%]
32767*2^4166145-1 is not prime. LLR Res64: 8747901D78B0169E Time : 17872.369 sec.
Iter: 3199351/4167088, ERROR: ROUND OFF (0.4375) > 0.4
Continuing from last save file.
Resuming LLR test of 32767*2^4167089-1 at iteration 3138177 [75.30%]
Disregard last error. Result is reproducible and thus not a hardware problem.
For added safety, redoing iteration using a slower, more reliable method.
Continuing from last save file.
Resuming LLR test of 32767*2^4167089-1 at iteration 3199351 [76.77%]
32767*2^4167089-1 is not prime. LLR Res64: FC9EA26582754D15 Time : 16371.428 sec.
32767*2^4167969-1 is not prime. LLR Res64: 2C7A5AAC66CEE7AB Time : 21888.822 sec.
32767*2^4169313-1 is not prime. LLR Res64: D6346C9A9DFD1741 Time : 27292.371 sec.
32767*2^4170129-1 is not prime. LLR Res64: 92DC3BCE468BF006 Time : 23650.646 sec.
32767*2^4171521-1 is not prime. LLR Res64: C0328AB23FF9D5EE Time : 26452.741 sec.
32767*2^4174049-1 is not prime. LLR Res64: B6E7884E3EF49372 Time : 25588.219 sec.
32767*2^4175585-1 is not prime. LLR Res64: 60616D1A3DC4E7DA Time : 24240.461 sec.
32767*2^4177169-1 is not prime. LLR Res64: DB105BFDECD92593 Time : 20327.782 sec.
32767*2^4178369-1 is not prime. LLR Res64: D6C8FF91B305244A Time : 25175.016 sec.
32767*2^4179489-1 is not prime. LLR Res64: E2E9122DFE3E2F1A Time : 25580.794 sec.
32767*2^4180833-1 is not prime. LLR Res64: 5B9AF4626030882E Time : 27378.527 sec.
32767*2^4182065-1 is not prime. LLR Res64: DF4ED9E813C6C8E7 Time : 25302.748 sec.
32767*2^4183425-1 is not prime. LLR Res64: EDAD4835AE5F9E02 Time : 25071.799 sec.
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Old 2020-12-18, 02:58   #38
masser
 
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Are you crossing an FFT boundary?
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Old 2020-12-18, 03:02   #39
VBCurtis
 
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These are tests right on the cusp of two FFT lengths. The longer FFT is necessary to avoid the roundoff errors, and LLR is smart enough to use the longer FFT on subsequent tests.

Check your screen display for FFT size to confirm or refute that a larger FFT is being used. This is desirable behavior, so you don't want a workaround.
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Old 2020-12-18, 15:47   #40
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I am running it in textmode nohupped of course - not graphical.

Had restarted all the 4 processes. This specific proces now has 2 new outputs, see the last 2 outputs below. A lot faster again...

32767*2^4179489-1 is not prime. LLR Res64: E2E9122DFE3E2F1A Time : 25580.794 sec.
32767*2^4180833-1 is not prime. LLR Res64: 5B9AF4626030882E Time : 27378.527 sec.
32767*2^4182065-1 is not prime. LLR Res64: DF4ED9E813C6C8E7 Time : 25302.748 sec.
32767*2^4183425-1 is not prime. LLR Res64: EDAD4835AE5F9E02 Time : 25071.799 sec.
Iteration 1706797 / 4184225
32767*2^4184225-1 is not prime. LLR Res64: 9531FBEF2A7307A8 Time : 22511.542 sec.
32767*2^4186929-1 is not prime. LLR Res64: 667011F7E43C9E4D Time : 19650.986 sec.
diep@thegathering:~/riesel$
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Old 2020-12-18, 22:41   #41
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My LLRTools data for Yorkfield lists the cutoff for k=32767 between FFT lengths 336K and 384K at 4168512, and my Haswell data is similar, so this appears to be an FFT boundary.

To get the FFT length info, pass the -d flag on the command line.

Last fiddled with by Happy5214 on 2020-12-18 at 22:43
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Old 2020-12-18, 23:59   #42
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Quote:
Originally Posted by Happy5214 View Post
My LLRTools data for Yorkfield lists the cutoff for k=32767 between FFT lengths 336K and 384K at 4168512, and my Haswell data is similar, so this appears to be an FFT boundary.

To get the FFT length info, pass the -d flag on the command line.
As you see i compare timings from above the boundary - so i compare the same FFT lengths with each other.

Restarting it's faster as VBCurtis explained why that's the case.
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Old 2020-12-19, 00:02   #43
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Had restarted all 4 times at the same time now we see big improvement in timings the last few LLR's again at 2 processes (each proces gets 2 cores, the box has 8 in total), as we would expect because of VBCurtis explanation:

$ tail test[1-4]/lresults.txt

=> test1/lresults.txt <==
32767*2^4178369-1 is not prime. LLR Res64: D6C8FF91B305244A Time : 25175.016 sec.
32767*2^4179489-1 is not prime. LLR Res64: E2E9122DFE3E2F1A Time : 25580.794 sec.
32767*2^4180833-1 is not prime. LLR Res64: 5B9AF4626030882E Time : 27378.527 sec.
32767*2^4182065-1 is not prime. LLR Res64: DF4ED9E813C6C8E7 Time : 25302.748 sec.
32767*2^4183425-1 is not prime. LLR Res64: EDAD4835AE5F9E02 Time : 25071.799 sec.
Iteration 1706797 / 4184225
32767*2^4184225-1 is not prime. LLR Res64: 9531FBEF2A7307A8 Time : 22511.542 sec.
32767*2^4186929-1 is not prime. LLR Res64: 667011F7E43C9E4D Time : 19650.986 sec.
32767*2^4187585-1 is not prime. LLR Res64: 74CCDDC491CBBC67 Time : 20588.003 sec.
32767*2^4190001-1 is not prime. LLR Res64: C5DDDD4D65A2D4DA Time : 20514.303 sec.

==> test2/lresults.txt <==
32767*2^4184913-1 is not prime. LLR Res64: 91CC53B73DECC4A5 Time : 19405.763 sec.
32767*2^4187105-1 is not prime. LLR Res64: 581ABB66BE0A6A0D Time : 19405.110 sec.
32767*2^4188033-1 is not prime. LLR Res64: 50454C639A29F322 Time : 20873.789 sec.
32767*2^4190273-1 is not prime. LLR Res64: 36D4EDC1045BE7CC Time : 18767.328 sec.
32767*2^4191633-1 is not prime. LLR Res64: DDF3B5B0620E6F6D Time : 20740.177 sec.
Iteration 1739046 / 4192833
32767*2^4192833-1 is not prime. LLR Res64: 90FF762361BD5B42 Time : 18954.435 sec.
32767*2^4195505-1 is not prime. LLR Res64: 6F7BD4194D5A4146 Time : 20401.832 sec.
32767*2^4196225-1 is not prime. LLR Res64: C37DBA10B425A841 Time : 20717.100 sec.
32767*2^4198673-1 is not prime. LLR Res64: 1090DEB866C017B7 Time : 20339.577 sec.

==> test3/lresults.txt <==
32767*2^4180305-1 is not prime. LLR Res64: 27B6A279CC19687A Time : 25012.032 sec.
32767*2^4181825-1 is not prime. LLR Res64: D23478428F6F991A Time : 24829.173 sec.
32767*2^4183233-1 is not prime. LLR Res64: 91A485F04DDEA5DA Time : 26954.555 sec.
32767*2^4183649-1 is not prime. LLR Res64: 4ECBA3026F3BD247 Time : 25344.495 sec.
32767*2^4185569-1 is not prime. LLR Res64: F4AA6D7BDFD427A3 Time : 23590.185 sec.
Iteration 2246443 / 4187265
32767*2^4187265-1 is not prime. LLR Res64: FAD65845FECD0A58 Time : 21362.924 sec.
32767*2^4188593-1 is not prime. LLR Res64: F84F1B176AC41BE2 Time : 16331.206 sec.
32767*2^4190721-1 is not prime. LLR Res64: 5109EFC983746880 Time : 16211.906 sec.
32767*2^4191729-1 is not prime. LLR Res64: 54A3272B2D19CF9A Time : 19655.511 sec.

==> test4/lresults.txt <==
32767*2^4186449-1 is not prime. LLR Res64: 6C13EED233CE10FF Time : 20702.989 sec.
32767*2^4187313-1 is not prime. LLR Res64: C2D6E4F84AD67621 Time : 20164.802 sec.
32767*2^4189905-1 is not prime. LLR Res64: 8B5196F80A316ED8 Time : 20127.331 sec.
32767*2^4190913-1 is not prime. LLR Res64: F39F0D09297212C8 Time : 19915.178 sec.
32767*2^4192353-1 is not prime. LLR Res64: 0D13E6D5613C666E Time : 20785.073 sec.
Iteration 3452461 / 4193409
32767*2^4193409-1 is not prime. LLR Res64: 7A5CAC9E4EC65DB8 Time : 19600.347 sec.
32767*2^4195761-1 is not prime. LLR Res64: 639E6CFD1E6AF6E6 Time : 21593.866 sec.
32767*2^4197633-1 is not prime. LLR Res64: DA27FA27EAC4AFE0 Time : 21342.204 sec.
32767*2^4199105-1 is not prime. LLR Res64: 3742CE46FA420F78 Time : 20142.416 sec.

Last fiddled with by diep on 2020-12-19 at 00:02
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Old 2020-12-19, 01:32   #44
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You really shouldn't be trying to defeat the LLR decision to use the bigger FFT. A silent rounding error, while unlikely, is possible. I'd rather do one test at 25k seconds than a set of double-checks at 18k sec each because the results aren't as trustworthy.
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