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Iceberg

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Message 67848 - Posted: 28 Oct 2018, 9:13:47 UTC

I've got an N-Body simulation I received recently that is taking forever to complete. It will take more than 30 hours by my calculation to finish when other N-Body simulations take an hour or less. Do you know why this would be? I am attaching the properties of the WU here:

Application
MilkyWay@Home N-Body Simulation 1.72 (mt)
Name
de_nbody_10_24_2018_v172_20k__data_3_1540379102_9162
State
Task suspended by user
Received
26/10/2018 4:18:47 PM
Report deadline
07/11/2018 3:19:13 PM
Resources
4 CPUs
Estimated computation size
157,474 GFLOPs
CPU time
13:23:53
CPU time since checkpoint
00:00:27
Elapsed time
04:23:12
Estimated time remaining
05:55:39
Fraction done
12.331%
Virtual memory size
18.45 MB
Working set size
16.33 MB
Directory
slots/4
Process ID
13812
Progress rate
2.880% per hour
Executable
milkyway_nbody_1.72_windows_x86_64__mt.exe
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Profilemikey
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Message 67849 - Posted: 28 Oct 2018, 14:04:55 UTC - in response to Message 67848.  

I've got an N-Body simulation I received recently that is taking forever to complete. It will take more than 30 hours by my calculation to finish when other N-Body simulations take an hour or less. Do you know why this would be? I am attaching the properties of the WU here:

Application
MilkyWay@Home N-Body Simulation 1.72 (mt)
Name
de_nbody_10_24_2018_v172_20k__data_3_1540379102_9162
State
Task suspended by user
Received
26/10/2018 4:18:47 PM
Report deadline
07/11/2018 3:19:13 PM
Resources
4 CPUs
Estimated computation size
157,474 GFLOPs
CPU time
13:23:53
CPU time since checkpoint
00:00:27
Elapsed time
04:23:12
Estimated time remaining
05:55:39
Fraction done
12.331%
Virtual memory size
18.45 MB
Working set size
16.33 MB
Directory
slots/4
Process ID
13812
Progress rate
2.880% per hour
Executable
milkyway_nbody_1.72_windows_x86_64__mt.exe


Try suspending the unit and then restarting it.
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Iceberg

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Message 67850 - Posted: 28 Oct 2018, 23:35:49 UTC - in response to Message 67849.  

That didn't work. I may just have to bite the bullet and let it complete. Will take about 36 hours. Oh well.
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TB

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Message 67852 - Posted: 29 Oct 2018, 23:35:22 UTC - in response to Message 67849.  

I've had some like that. Some just took 5-9 hours. One went 17 hours. Currently there's this thing that has crunched for 10 hours and claims to have 17 to go:

Application
MilkyWay@Home N-Body Simulation 1.72 (mt)
Name
de_nbody_10_24_2018_v172_20k__data_1_1540379102_15905
State
Running
Received
10/27/2018 10:57:06 AM
Report deadline
11/8/2018 9:57:05 AM
Resources
4 CPUs
Estimated computation size
86,339 GFLOPs
CPU time
1d 15:23:52
CPU time since checkpoint
00:05:19
Elapsed time
10:39:53
Estimated time remaining
17:07:32
Fraction done
38.376%
Virtual memory size
40.31 MB
Working set size
37.50 MB
Directory
slots/4
Process ID
24988
Progress rate
3.600% per hour
Executable
milkyway_nbody_1.72_windows_x86_64__mt.exe

Don't like them. If there's an error it means a big chunk of time's devoted to something that's corrupted. It means that somebody else has to take another big chunk of time to crunch the numbers a 3rd time.
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Iceberg

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Message 67853 - Posted: 30 Oct 2018, 1:45:42 UTC - in response to Message 67852.  

TB, so I should just let it run anyway to save someone else the grief of having to deal with this one?
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TB

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Message 67854 - Posted: 30 Oct 2018, 10:20:05 UTC - in response to Message 67853.  

Dunno. I've gone back and said I don't want to run n-body simulations after this batch. At least for a while--I have to assume that "they" didn't plan for work units to be this large.
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Message 67855 - Posted: 30 Oct 2018, 15:23:57 UTC

Had a N-Body task error out with Disk usage limit exceeded error after consuming CPU time: 2 days 13 hours 11 min 8 sec.

Task 47513706

Milkyway@Home 1.72
MilkyWay@Home N-Body Simulation (mt)
de_nbody_10_24_2018_v172_20k__data_3_1540379102_25482_0
Reported: Computation error (196,)
Max Virtual RAM Used 32.84 MB
Max Physical RAM Used 34.13 MB

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Message 67856 - Posted: 30 Oct 2018, 16:22:06 UTC - in response to Message 67855.  

Thanks, TB and Dr Who Fan. I'll keep this in mind. I've suspended N-Body sims from after this one completes. Hoping they figure this out soon.
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Jim1348

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Message 67884 - Posted: 9 Nov 2018, 16:38:15 UTC

I use Windows 7 64-bit, and running 4 cores on an i7-4790 had a WU that ran for 19 hours. Now, running 6 cores on an i7-4771 machine, one has gone for 22 hours, with 14 hours remaining.

That is not a problem; I run my machines 24/7 anyway, but I wonder what has changed?
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Jim1348

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Message 67886 - Posted: 10 Nov 2018, 2:30:17 UTC - in response to Message 67884.  

Now, running 6 cores on an i7-4771 machine, one has gone for 22 hours, with 14 hours remaining.

That one ended with "Disk usage limit exceeded</message>".
https://milkyway.cs.rpi.edu/milkyway/result.php?resultid=56340476

I doubt that it is a limitation on my PC; I have 35 GB free, including the amount reserved by BOINC.
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Message boards : Number crunching : Very long N-Body simulation

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