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Are we really chasing the right issue?

Posted Feb 24, 2012 8:45 UTC (Fri) by dlang (✭ supporter ✭, #313)
In reply to: Are we really chasing the right issue? by rvfh
Parent article: Short sleeps suffering from slack

the owner of the system set the slack value, why should an application programmer of some random application get to override this?

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Posted Feb 24, 2012 9:29 UTC (Fri) by rvfh (subscriber, #31018) [Link]

Problem is:
* app dev says it should sleep 1 second
* sys owner says if you sleep, then you may sleep for 5 seconds

What do we do? Either
* sleep for 1 second, as requested, or
* sleep for up to 5 seconds and break the application

I think this calls for a new user-space API, such as:
unsigned int sleep_slack(unsigned int seconds, unsigned int slack);

But sleep's behaviour should not be changed.

Are we really chasing the right issue?

Posted Feb 24, 2012 9:55 UTC (Fri) by tglx (subscriber, #31301) [Link]

> But sleep's behaviour should not be changed.

The kernel does not change sleep() behaviour. It's the sysadmins choice to set slack to something large. The kernel provides the mechanism, but not the policy.