[syslog-ng] Profiling syslog-ng

[John Morrissey]

On Thu, Feb 16, 2006 at 09:56:30AM +0100, Balazs Scheidler wrote:
> On Wed, 2006-02-15 at 14:28 -0500, John Morrissey wrote:
> > FWIW, I modified syslog-ng 1.6.9 to usleep(10000) at the end of the
> > io_iter() loop in src/main.c. This dropped CPU consumption by about fourfold
> > - instead of spinning in that io_iter() loop, reading one or two messages
> > per poll(), it's now reading several (3-15) messages per poll().
> 
> The idea is cool, although I have to admit it is really a hack :)
> 
> This might be useful to others as well. I will probably add it as a
> global option. Thanks for tracking this down.

I pulled the time_sleep() changes from a recent snapshot (thanks!) and am
backporting them to 1.6.x[1]. I noticed this hunk:

+       if (backend->configuration->time_sleep > 0)
+       {
+           struct timespec ts;
+
+           ts.tv_sec = 0;
+           ts.tv_nsec = backend->configuration->time_sleep * 1000;
+
+           nanosleep(&ts, NULL);

The docs say the time_sleep() value is in milliseconds, but
1 msec == 1 000 000 nsec - shouldn't this multiplication factor have an
extra three zeros? :-)

john

[1] http://horde.net/~jwm/software/misc/10_configurable_sleep.diff
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