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ionice limits process I/O, to keep it from swamping the system (Linux)

Terminal - ionice limits process I/O, to keep it from swamping the system (Linux)
ionice -c3 find /
2009-02-19 17:23:12
User: mkc
Functions: find
ionice limits process I/O, to keep it from swamping the system (Linux)

This command is somewhat similar to 'nice', but constrains I/O usage rather than CPU usage. In particular, the '-c3' flag tells the OS to only allow the process to do I/O when nothing else is pending. This dramatically increases the responsiveness of the rest of the system if the process is doing heavy I/O.

There's also a '-p' flag, to set the priority of an already-running process.


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What others think

The -c3 refers to the idle priority class, which according to the manpage is only permitted for root. Therefore the line should read:

# ionice -c3 find /

Comment by markrian 442 weeks and 5 days ago

Erm, having now tried it, it seems the manpage is talking rubbish. Any user can change their own processes to idle priority!

Comment by markrian 442 weeks and 5 days ago

Yeah, I'm a little unclear on this. It seems like I was able to do it as a regular user at some point, but now maybe root is required. I think non-root access to this is considered to be a security hole (for somewhat obscure reasons).

Comment by mkc 442 weeks and 4 days ago

Your point of view

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