Re: Severe performance degradation on Linux

Hi,


On Tue, Jan 6, 2015 at 1:28 PM, Michael Meeks <michael.meeks@collabora.com>
wrote:
>         As Tor suggested doing an strace on each end would show what's up:
>
>         strace -f -ttt -s 256 -o /tmp/slog slow_proces
>
>         And poke in the /tmp/slog for where there is a multi-second jump
in the
> time - and paste a dozen lines or so around that in each direction =)


Well I tried this, and it produced a file of a whopping 383087 lines and 30
MB. I wouldnt expect any sane person to look through all of that in its
entirety on a page by page basis.
;)

I guess that means I cant figure out what's going on. Which leaves me with
one last question:

Are the large amounts of 'futex(FUTEX_WAIT_PRIVATE) /
futex(FUTEX_WAKE_PRIVATE)' expected behavior in this case ? I dont know
enough about it to make the call, but it seems to me that inefficient
locking may lead to performance issues. Also, futex() is as far as I can
tell, a penguin-ism and not available on Mac which may account for the
difference ?

Just my 2$, please feel free to correct my incorrect assumptions.
;)


Anyway, thanks for all the help.


- Maarten