Tasks available / different between computers


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Questions and Answers : Preferences : Tasks available / different between computers

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Maczor
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Message 1272178 - Posted: 17 Aug 2012, 17:11:40 UTC

I have two computers, both in the same room. Computer A had some tasks to report so I did manual update, it reported the tasks and got about 50 new tasks. Great! I then immediately went to Computer B. Computer B had a few tasks to report but it was down to it's last 4 tasks (it has 4 cpus so it does 4 at a time). I did a manual update on Computer B, it sent the completed tasks, but it responded with "Project has no tasks available".

So now I have Computer A with a queue of about 80 tasks and Computer B has only 4 tasks that it will complete in the next 1-3 hours.

I'm confused why the project had tasks for Computer A but not Computer B.

Also is there a way to move tasks from Computer A to Computer B so that both computers can stay crunching?

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Message 1272183 - Posted: 17 Aug 2012, 17:19:38 UTC - in response to Message 1272178.

I have two computers, both in the same room. Computer A had some tasks to report so I did manual update, it reported the tasks and got about 50 new tasks. Great! I then immediately went to Computer B. Computer B had a few tasks to report but it was down to it's last 4 tasks (it has 4 cpus so it does 4 at a time). I did a manual update on Computer B, it sent the completed tasks, but it responded with "Project has no tasks available".

So now I have Computer A with a queue of about 80 tasks and Computer B has only 4 tasks that it will complete in the next 1-3 hours.

I'm confused why the project had tasks for Computer A but not Computer B.

Also is there a way to move tasks from Computer A to Computer B so that both computers can stay crunching?


To answer your last question first, yes, it CAN be done, but it's highly NOT recommended due to the complexity of the process and the fact that you'd have to move the work back to the first system to report it.

Assignment of work is always based on what happens to be available at the moment you hit the update button. With thousands of systems all looking for work (since we're coming out of a planned outage which lasted close to 48 hours), it's more surprising to me that you got 50 units at once than that you got 0 right after.
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Message 1272214 - Posted: 17 Aug 2012, 17:49:09 UTC

Thanks for the reply. I won't try and move tasks to another computer as it does sound like more work than it is worth. I guess I'll just keep checking for new tasks on Computer B until some are available.

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Message 1272227 - Posted: 17 Aug 2012, 18:05:52 UTC

The answer is simple - the feeder stream at S@H contains 100 WU, and is refilled automatically when all the WU are assigned to a cruncher. If you make a call for new work and there are no WU in the feeder stream you get the "No work available". The refill and emptying rates are quite high, so the delay between no work being available and some being there is quite short (I think it is below a second), but the number of users making work requests is very high...

As to moving tasks between computers, don't, it can upset all sorts of things, not the least of which are the servers because they where they sent each and every task, and expect them all to come back from the correct server.
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Message 1272373 - Posted: 18 Aug 2012, 0:29:35 UTC - in response to Message 1272227.

The answer is simple - the feeder stream at S@H contains 100 WU, and is refilled automatically when all the WU are assigned to a cruncher. If you make a call for new work and there are no WU in the feeder stream you get the "No work available". The refill and emptying rates are quite high, so the delay between no work being available and some being there is quite short (I think it is below a second), but the number of users making work requests is very high...

As to moving tasks between computers, don't, it can upset all sorts of things, not the least of which are the servers because they where they sent each and every task, and expect them all to come back from the correct server.

I believe that it is once a second that it is refilled. If it empties in the first tenth of a second, it will stay empty for the next nine tenths of a second. Situations like this happen all the time just after an outage as many computers are out of work.
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Questions and Answers : Preferences : Tasks available / different between computers

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