Re: [patch 4 15/22] timer: Remove slack leftovers

From: Jason A. Donenfeld
Date: Fri Jul 22 2016 - 11:18:17 EST

Hi Thomas,

On Fri, Jul 22, 2016 at 3:04 PM, Thomas Gleixner <tglx@xxxxxxxxxxxxx> wrote:
> Well, this really depends on the TIMEOUT value you have. The code now does
> implicit batching for larger timeouts by queueing the timers into wheels with
> coarse grained granularity. As long as your new TIMEOUT value ends up in the
> same bucket then that's equivalent to the slack thing.
> Can you give me a ballpark of your TIMEOUT value?

Generally either 5 seconds, 10 seconds, or 25 seconds.

Are these okay? Is the 25 case substantially different from the 5 case?

> When you take the slow (queueing) path, it's still expensive, not as bad as
> the previous one, but not really cheap either.

Hmm, okay.