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farta
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confused Why BOINC not execute near expiring WUs first?

I'm caching WUs more than default. I'm aware that algorithm for sorting and picking up WUs from cache is inexplicable. Right now it is about 9/10/2015 11:00 local time, 4 tasks with ETA between 9/17 & 9/20 are running, 23 WUs are in cache queue, and 4 tasks with ETA 9/13 seems at the end of the queue.

I'm worrying about if it would cause WU expire. Is there an option about priority algorithm (which I may changed by mistake)? Or is there a flaw in BOINC's algorithm? Or is there nothing to be worried about, BOINIC would guarantee WU won't expire due to not executing them in time?
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Former Member
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Re: Why BOINC not execute near expiring WUs first?

Not quite inexplicable, but close wink. The basis of scheduling is FIFO, First In First Out, no matter the deadline. Only when there's a deadline-exceed threat will jobs move in the EDF, Earliest Deadline First order, automatically (and some will debate this). BOINC has though some safeties build-in. For instance the shorter deadline tasks are moved ahead if half of their deadline has already been used up. If though there is so much cached that everything starts running in 'panic' mode, you're in trouble. This is why the rule of thumb is to never cache more than half of the shortest deadline project you participate in. E.g. if the MCM repairs are due in 2.8 days and your buffer is greater than 1.4 days worth of work, these MCM repairs will be scheduled ahead quite soon. A second safety is, that clients that do not return work within 48 hours will not get those repair / short deadline jobs. The [WCG] server keeps track of what to assign.

In a nutshell
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[Edit 1 times, last edit by Former Member at Sep 10, 2015 7:37:37 AM]
[Sep 10, 2015 7:35:42 AM]   Link   Report threatening or abusive post: please login first  Go to top 
Former Member
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Re: Why BOINC not execute near expiring WUs first?

BTW, the rescheduling algorithm runs ones per minute or 10 seconds, don't quite remember. It re-computes total estimated buffer runtime needed to process all tasks and then assesses if EDF is required for any task in the buffer.
[Sep 10, 2015 7:40:38 AM]   Link   Report threatening or abusive post: please login first  Go to top 
farta
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Re: Why BOINC not execute near expiring WUs first?

Not quite inexplicable, but close wink. The basis of scheduling is FIFO, First In First Out, no matter the deadline. Only when there's a deadline-exceed threat will jobs move in the EDF, Earliest Deadline First order, automatically (and some will debate this). BOINC has though some safeties build-in. For instance the shorter deadline tasks are moved ahead if half of their deadline has already been used up. If though there is so much cached that everything starts running in 'panic' mode, you're in trouble. This is why the rule of thumb is to never cache more than half of the shortest deadline project you participate in. E.g. if the MCM repairs are due in 2.8 days and your buffer is greater than 1.4 days worth of work, these MCM repairs will be scheduled ahead quite soon. A second safety is, that clients that do not return work within 48 hours will not get those repair / short deadline jobs. The [WCG] server keeps track of what to assign.

In a nutshell


Thanks a lot. I'm running FAAH & MCM, caching 0.5 day of task. I guess it would be OK. biggrin
[Sep 11, 2015 4:18:21 AM]   Link   Report threatening or abusive post: please login first  Go to top 
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