Dynamic Ticks/HZ

Ryan Stone rysto32 at gmail.com
Mon Nov 5 13:11:42 UTC 2012


On Mon, Nov 5, 2012 at 4:40 AM, Joe Holden <lists at rewt.org.uk> wrote:

> doh, running kernel wasn't as GENERIC as I thought it was, looks like
> device polling not only breaks dynamic ticks but also reduces rx ability
> significantly, exactly 150,000 pps per 1000hz on igb versus 650,000 without
>
> Is this a known issue? (and if device polling isn't as useful as it once
> was, should it be removed?)
>

Device polling on modern multiqueue NICs isn't very useful because you're
limited to a single thread for handling packets.  I have a patch that fixes
this that I've let fall by the wayside.


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