reserve
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reserve [2017/08/31 16:09] – mimbert | reserve [2022/08/30 10:39] – mimbert | ||
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+ | Despite this syntax being not user-friendly, | ||
+ | * Nodes are often shutdown, in energy saving mode. Booking only the needed nodes ensures that only these ones will be wakeup. This contributes to increase node lifetime and saving energy | ||
+ | * As only needed nodes are asked, it avoids your oar job being canceled or postponed in case one node that you don't use is unavailable | ||
+ | * It allows tracing more accurately resources usage | ||
+ | |||
+ | ==== Booking the room without any node ==== | ||
+ | |||
+ | You can book the room only, without any node with the following syntax: | ||
+ | |||
+ | < | ||
+ | |||
+ | This is useful in particular if you want to go physically in the room for experimenting with specific hardware, because it avoids waking any node if they are in energy saving mode. | ||
+ | |||
+ | ==== A note on OAR job scheduling ==== | ||
+ | |||
+ | Be aware that OAR behaviour may sometimes be counter-intuitive: | ||
+ | * because the nodes are currently shutdown, so it needs to wake them up, which may take some time | ||
+ | * because another job is running | ||
+ | * because the resources you ask are currently not available but oar expects them to be available in the future | ||
+ | * etc. | ||
+ | So, the only reliable way to be sure that your job is actually running is to check that the job's state is " | ||
+ | |||
+ | < | ||
+ | |||
+ | Tasks submitted to minus will never start unless the job is " | ||
+ | |||
+ | ==== A note on energy saving ==== | ||
+ | |||
+ | When nodes are unused, and after a timeout, they will be automatically shutdown (and will appear as " | ||
+ | |||
+ | When a job is submitted, shutdown nodes are waken up. Thus the job will not start immediately, | ||
+ | |||
+ | When there is a reservation, | ||
==== Advanced usage: sharing the platform ==== | ==== Advanced usage: sharing the platform ==== |
reserve.txt · Last modified: 2022/11/18 16:43 by pgirard