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Re: serious performance regression in .41



On 22 May 2014, at 03:15, Christos Zoulas <christos%astron.com@localhost> wrote:

> In article <lljiob$ha3$1%ger.gmane.org@localhost>,
> Christos Zoulas <christos%astron.com@localhost> wrote:
> 
>> Here's an ugly fix (but internally only ugly fix):
>> 
>> http://www.netbsd.org/~christos/mntvnode_lock.diff

Only unmount will use vflush() so this will not help.

> Although this improves the situation the machine still has large pauses.
> - compile a kernel with lockdebug.

No performance tests with LOCKDEBUG or DEBUG please.  These options
are known to be very expensive.

> - start a build
> - hold a key down at the shell prompt and notice how it behaves
> 
> Every 3 or so lines (of 80 characters), you'll notice a large pause
> where the machine is unresponsive for a couple of seconds, and then comes 
> back.

I'm not able to reproduce this behaviour here.  Please describe
your setup (mounted file systems and build command) in more detail.

Will "systat vmstat 1" show anything during the pause?

--
J. Hannken-Illjes - hannken%eis.cs.tu-bs.de@localhost - TU Braunschweig 
(Germany)



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