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ATLAS application :
Best number of cores on a 16 core machine to use for ATLAS
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Send message Joined: 28 Dec 08 Posts: 341 Credit: 5,096,087 RAC: 2,428 ![]() ![]() ![]() |
With 16 cores I am currently using only 4 for ATLAS. But what is the best use for a single task? 4 or 6 or 8? How should the CPU% be showing while the task is working? I see a high percentage on start up up to .70% of 4 cores and then if I come back in an hour or so it drops to .03% of 4 cores and is clicking off about .10% completion every 2 seconds (BoincTasks monitoring). What is it doing? Simulated runs first and then data analysis afterwards? I am trying to understand the process so I can better tell when a task is stuck (a .001% per 2 seconds completion time usually marks a stall) or when it is running normal. What does it do after the first so called 15 seconds of run time vs elapsed time of 4 hours plus to complete the task? |
Send message Joined: 28 Dec 08 Posts: 341 Credit: 5,096,087 RAC: 2,428 ![]() ![]() ![]() |
And now after 7 hours run time on 4 cores it bogs down. Now only moving forward at .004% per 2 seconds on .02% cpu power. Stderr file output: 2021-05-01 21:12:02 (19856): Setting CPU throttle for VM. (100%) 2021-05-01 21:12:02 (19856): Setting checkpoint interval to 900 seconds. (Higher value of (Preference: 180 seconds) or (Vbox_job.xml: 900 seconds)) 2021-05-01 23:18:28 (19856): Status Report: Elapsed Time: '12802.115137' 2021-05-01 23:18:28 (19856): Status Report: CPU Time: '19.859375' 2021-05-02 01:12:39 (19856): Status Report: Elapsed Time: '18802.115137' 2021-05-02 01:12:40 (19856): Status Report: CPU Time: '23.484375' This stinks. |
![]() Send message Joined: 12 Jun 18 Posts: 126 Credit: 53,906,164 RAC: 0 ![]() ![]() |
what is the best use for a single task?One. |
Send message Joined: 28 Dec 08 Posts: 341 Credit: 5,096,087 RAC: 2,428 ![]() ![]() ![]() |
yeah i might have to try that being i blew up a bunch of tasks already with 4 and 8. I used to be able to run ATLAS with 4 no problem, its 50/50 now with 4. |
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