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Time calculation way off

Time calculation way off

Message boards : Number crunching : Time calculation way off
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blyons123

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Message 54837 - Posted: 26 Sep 2016, 13:04:44 UTC

Even though my CPU benchmark runs every few days. ALL the tasks are off by 2-3 times time estimation!? A "5 day" actually takes 12-15 days.
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Profile Iain Inglis
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Message 54838 - Posted: 26 Sep 2016, 14:04:06 UTC - in response to Message 54837.  
Last modified: 26 Sep 2016, 14:04:38 UTC

BOINC Manager estimates the model run time in advance based on information supplied with the model (the GFLOPS estimate) and the time it actually took to run models in the past. The BOINC Manager estimates may be inaccurate when a new machine joins the project but tend to get better slowly.

There is a second effect, however, which is that the model may take longer to run than it should. Here, for example, is a model completed by your machine, wah2_mex50_ken2_193512_13_436_010687296_0. The reported "run-time" and "CPU time" differ by quite a lot:

Run time 639,500.57
CPU time 558,190.60

A comparable MEX50 on one of my machines has the following:

Run time 424,636.00
CPU time 423,956.60

The reason for this may be the BOINC Manager setting that keeps models in memory when suspended. That's set on mine and not on yours, as is apparent in the stdout log of your completed model:

<core_client_version>7.6.22</core_client_version>
<![CDATA[
<stderr_txt>
onitor - Suspend request from BOINC...
Suspended CPDN Monitor - Suspend request from BOINC...
Suspended CPDN Monitor - Suspend request from BOINC...
Suspended CPDN Monitor - Suspend request from BOINC...
Suspended CPDN Monitor - Suspend request from BOINC...
Suspended CPDN Monitor - Suspend request from BOINC...
Suspended CPDN Monitor - Suspend request from BOINC...


Try changing the setting in BOINC Manager (Options | Computing preferences | Disk and memory, then tick the "Leave non-GPU tasks in memory while suspended" box) - and see whether things improve.
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Profile Dave Jackson
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Message 54846 - Posted: 27 Sep 2016, 8:34:08 UTC

What I fail to understand is when by highlighting a task and clicking on properties you can see the percentage/hour. It can not be difficult for BOINC to calculate time remaining based on this. (This is only relevant once a task has started.
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WB8ILI

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Message 54848 - Posted: 27 Sep 2016, 13:15:39 UTC

Dave Jackson -

I have noticed that too. One value is elapsed time and the other is the amount of computational time left (apples and oranges comparison). Maybe the percent has something to do with the percent of time steps completed and nothing to do with any times.

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Message boards : Number crunching : Time calculation way off

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