How can I run a job when the server load is low?

Posted by jberryman on Server Fault See other posts from Server Fault or by jberryman
Published on 2010-04-14T23:15:36Z Indexed on 2010/04/14 23:23 UTC
Read the original article Hit count: 261

Filed under:

linux

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bash

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ec2

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scheduled-task

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cron

I have a command that runs a disk snapshot (on EC2, freezing an XFS disk and running an EBS snapshot command), which is set to run on a regular schedule as a cron job. Ideally I would like to be able to have the command delayed for a period of time if the disk is being used heavily at the moment the task is scheduled to run.

I'm afraid that using nice/ionice might not have the proper effect, as I would like the script to run with high priority while it is running (i.e. wait for a good time, then finish fast).

Thanks.

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