How to receive shorter tasks?

Message boards : Number crunching : How to receive shorter tasks?

To post messages, you must log in.

AuthorMessage
reboot81

Send message
Joined: 11 Apr 20
Posts: 2
Credit: 2,768,359
RAC: 0
Message 94543 - Posted: 15 Apr 2020, 14:17:33 UTC

I have a couple of computers that are available at night, but the tasks take ~30 hours or more to complete. The CPUs are available from 21:00-06:00. Given the 3 day deadline I'm unable to use these since 9h*3days=27hours.

How do I solve this issue?

I'm using 7.16.5 x64 on Win10.
Rosetta@home preferences: Target CPU run time: 2 hours

However this settings is not reflected in the tasks I receive.
ID: 94543 · Rating: 0 · rate: Rate + / Rate - Report as offensive    Reply Quote
Bryn Mawr

Send message
Joined: 26 Dec 18
Posts: 392
Credit: 12,097,254
RAC: 5,585
Message 94550 - Posted: 15 Apr 2020, 16:05:57 UTC - in response to Message 94543.  

I have a couple of computers that are available at night, but the tasks take ~30 hours or more to complete. The CPUs are available from 21:00-06:00. Given the 3 day deadline I'm unable to use these since 9h*3days=27hours.

How do I solve this issue?

I'm using 7.16.5 x64 on Win10.
Rosetta@home preferences: Target CPU run time: 2 hours

However this settings is not reflected in the tasks I receive.


It looks as though you may have received some faulty WUs that got stuck in a loop. Rosetta tasks are time limited, they will stop at the closest end point to your target run time and there is a watchdog function that should force them to abort if they overrun by more than 4 hours.
ID: 94550 · Rating: 0 · rate: Rate + / Rate - Report as offensive    Reply Quote
Mod.Sense
Volunteer moderator

Send message
Joined: 22 Aug 06
Posts: 4018
Credit: 0
RAC: 0
Message 94558 - Posted: 15 Apr 2020, 17:39:05 UTC - in response to Message 94543.  

Your machines are hidden, so there are not details to examine to help you further.

Setting the runtime preference lower is indeed the proper thing to do for your situation. What was it set to before? That setting defines how long the task should run. There are cases where a model goes awry and the watchdog kicks in when your exceed the preference by more than 4 hours. Note that these 4 hours are 4 hours of CPU time, not elapsed time. Look at the properties of active tasks. Do you see a large difference between CPU time and elapsed time? If so, it would tend to indicate your machine is busy running other work, or perhaps has some memory contention. How many cores does the machine have? How much memory? How much of the memory and CPU is BOINC configured to use?
Rosetta Moderator: Mod.Sense
ID: 94558 · Rating: 0 · rate: Rate + / Rate - Report as offensive    Reply Quote
reboot81

Send message
Joined: 11 Apr 20
Posts: 2
Credit: 2,768,359
RAC: 0
Message 94742 - Posted: 18 Apr 2020, 9:50:08 UTC - in response to Message 94558.  

Sorry for not providing sufficient detail in my first post:

The machines are desktop i5 quad 8GB/SSD/1Gb network with nothing running on them besides Boinc. I changed runtime to 4h several days ago. Runtime is within +-10% CPU time. Machines are set to have one free core, 75 % of CPU time, RAM 50% in use, RAM 80% not in use. Suspend when computer is in use (no), Suspend when non-BOINC CPU usage is above 25%

I do receive short tasks - some 2-3 hours on the same client that recieved a 25 hour task. So things are improving :)
Give it a week or so and see how things are going.

-Should I expect to only receive shorter task when set a low runtime IF there are available matching tasks, and when there no available shorter tasks I'll receive whatevers available, even longer tasks?
ID: 94742 · Rating: 0 · rate: Rate + / Rate - Report as offensive    Reply Quote
Bryn Mawr

Send message
Joined: 26 Dec 18
Posts: 392
Credit: 12,097,254
RAC: 5,585
Message 94745 - Posted: 18 Apr 2020, 10:01:48 UTC - in response to Message 94742.  

Sorry for not providing sufficient detail in my first post:

The machines are desktop i5 quad 8GB/SSD/1Gb network with nothing running on them besides Boinc. I changed runtime to 4h several days ago. Runtime is within +-10% CPU time. Machines are set to have one free core, 75 % of CPU time, RAM 50% in use, RAM 80% not in use. Suspend when computer is in use (no), Suspend when non-BOINC CPU usage is above 25%

I do receive short tasks - some 2-3 hours on the same client that recieved a 25 hour task. So things are improving :)
Give it a week or so and see how things are going.

-Should I expect to only receive shorter task when set a low runtime IF there are available matching tasks, and when there no available shorter tasks I'll receive whatevers available, even longer tasks?


If the machines are exclusively Boinc then why restrict the ram when not in use? At 8Gb the ram is quite tight anyway.

Also, it is generally considered better to leave %CPU at 100 and if you need to restrict the amount of processing, change the % of cores to 75 instead - the perceived wisdom is that this is kinder to the CPU.
ID: 94745 · Rating: 0 · rate: Rate + / Rate - Report as offensive    Reply Quote
Profile Grant (SSSF)

Send message
Joined: 28 Mar 20
Posts: 1679
Credit: 17,802,865
RAC: 22,539
Message 94746 - Posted: 18 Apr 2020, 10:03:26 UTC - in response to Message 94742.  
Last modified: 18 Apr 2020, 10:04:46 UTC

Runtime is within +-10% CPU time.
Ideally the difference between Run time & CPU time should be only a couple of minutes at most for a 4hr run time. If the computer is being used, with programmes requiring a fair amount of CPU resources then it explains the larger difference, otherwise use Task Manager or Process explorer to see what else is using CPU time.



Suspend when non-BOINC CPU usage is above 25%
Even just a script on a web page can push CPU usage well over that. If not happy with that option disabled all together, i'd suggest 85% or higher. Rosetta runs at Idle priority, so pretty much everything else will get CPU time in preference to Rosetta so no real need to suspend even if non BOINC usage is 100%.



Should I expect to only receive shorter task when set a low runtime IF there are available matching tasks, and when there no available shorter tasks I'll receive whatevers available, even longer tasks?
Any task you run should only Run for the Target CPU time you set. If it does run longer, it shouldn't run any longer than 4hrs or so and then the Watchdog timer will end it.
Having said that; we have been getting a few Tasks over the last few days that run well over their Target time, and well over the Watchdog timer 4 hour limit as well. And to add to that, they often have very large periods with no checkpointing (i've seen as much as 40min, others have reported no checkpointing for the entire Runtime).
Grant
Darwin NT
ID: 94746 · Rating: 0 · rate: Rate + / Rate - Report as offensive    Reply Quote

Message boards : Number crunching : How to receive shorter tasks?



©2024 University of Washington
https://www.bakerlab.org