* Mike Kravetz <[email protected]> wrote:
> On Wed, Sep 20, 2006 at 04:19:07PM +0200, Ingo Molnar wrote:
> > In particular, a nasty softirq performance bug has been fixed, which
> > caused the "5x slowdown under TCP" bug reported to lkml - those TCP
> > performance figures are now on par with vanilla performance.
>
> Just curious about the cause and fix for this issue. I tried
> searching the mail lists for discussion but came up empty. The patch
> it too big for me to determine what specific changes addressed this
> issue. If anyone can point me in the right direction, that would be
> appreciated.
i /think/ it's this bit of code commented out in kernel/softirq.c:
//if (!in_interrupt() && local_softirq_pending())
// invoke_softirq();
try to uncomment that. (this should i think do the trick on PREEMPT_RT -
but no guarantees. It might cause problems on !PREEMPT_RT configs, i had
to juggle around some code here. Maybe the easiest would be if you tried
to take the new softirq.c, sans the lockdep changes. Not sure how
feasible that is though.)
Ingo
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
