Messages in this thread |  | | | Date | Mon, 17 Nov 2008 12:39:10 -0500 (EST) | | From | Mikulas Patocka <> | | Subject | Re: Active waiting with yield() |
On Sat, 15 Nov 2008, Peter Zijlstra wrote:
> On Fri, 2008-11-14 at 16:41 -0500, Mikulas Patocka wrote:
>
> > So, use msleep(1) instead of yield() ?
>
> wait_event() of course!
Why? Why developes don't like active waiting when terminating a driver?
Is there any real workload when 1ms delay on driver unload would be
problematic? Or don't they like it because of coding style?
L1 cache miss --- 10ns --- on every request, when using wait queues
msleep latency --- 1ms --- on driver termination, when using msleep
--- so if the driver processes more than 100000 requests between reboots,
wait queues actually slow things down.
Mikulas
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