Re: serious performance regression in .41

[christos%astron.com@localhost (Christos Zoulas)]

In article <2B9BF96F-5DB2-4B91-8FD0-A01F0F455C16%eis.cs.tu-bs.de@localhost>,
J. Hannken-Illjes <hannken%eis.cs.tu-bs.de@localhost> wrote:
>On 22 May 2014, at 13:27, Christos Zoulas <christos%astron.com@localhost> 
>wrote:
>
>> In article <0E8BFCFC-C4CD-4CE3-8BAC-22EB8EBD3471%eis.cs.tu-bs.de@localhost>,
>> J. Hannken-Illjes <hannken%eis.cs.tu-bs.de@localhost> wrote:
>>> On 22 May 2014, at 03:15, Christos Zoulas <christos%astron.com@localhost> 
>>> wrote:
><snip>
>> 
>>>> - 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.
>> 
>> The build command is standard. I have raid over sd0 (SAS drives).
>> How much memory do you have? Leave enough time for the buffer cache
>> to fill up.
>
>It is 16 CPU / 16 GB virtual machine on KVM/CentOS6.

8 real CPUs, no VM.

>The output of "mount" and the raid level could help, any tuning
>with "sysctl"?

No tuning.

It worked fine before the changes...

I am testing this now:

http://www.netbsd.org/~christos/vnode_iterator.diff

christos