Re: RCU latency regression in 2.6.16-rc1

[Lee Revell]

On Tue, 2006-01-24 at 09:01 +0100, Ingo Molnar wrote:
> * Lee Revell <rlrevell@xxxxxxxxxxx> wrote:
> 
> > On Tue, 2006-01-24 at 08:56 +0100, Ingo Molnar wrote:
> > > * Lee Revell <rlrevell@xxxxxxxxxxx> wrote:
> > > 
> > > > I ported the latency tracer to 2.6.16 and got this 13ms latency within 
> > > > a few hours.  This is a regression from 2.6.15.
> > > > 
> > > > It appears that RCU can invoke ipv4_dst_destroy thousands of times in 
> > > > a single batch.
> > > 
> > > could you try the PREEMPT_RCU patch below?
> > 
> > Sure.  If it works do you see this making it in 2.6.16?  Otherwise we 
> > still would have a regression...
> 
> nope, that likely wont make v2.6.16, which is frozen already.
> 

Well, the last latency regression I found, I was told "I wish you'd
caught this at 2.6.15-rc1, something could have been done".  Now I've
found another one at the -rc1 stage, and there's still nothing that can
be done?

Lee

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/