[Pgpool-general] pgpool-II 2.2.5 slamming the CPU

[Glyn Astill]

--- On Tue, 24/11/09, Steven Crandell <steven.crandell at gmail.com> wrote:
> I'm seeing this also with
> pgpool-II-2.2.5 running on ubuntu server, kernel 2.6.24.
> Given pgpool's handling method for connections over the
> num_init_children (queuing), I have to set num_init_children
> high enough to ensure children are never depleted (>
> 1000).
> 
> When all those children respawn every $child_life_time
> seconds I see load spikes upwards of 60
> 
> That said, there does not appear to be any operational
> impact on the pgpool server, I am just seeing load spikes
> similar to what Aleksey mentioned turning my monitoring
> solution red multiple times a day.
> 
> 
> I would think that one work around would be to set
> child_max_connections sufficiently low that children respawn
> because they have reached child_max_connections rather than
> than child_life_time.  If I'm understanding the
> situation correctly this would cause child respawns to
> happen more serially rather than all children respawning
> together every $child_life_time seconds.
> 

Hmm, the reason I asked about kernel version was that I started seeing these spikes after going from 2.6.18 to 2.6.26, that's not to say more subtle symptoms were not there before and I didn't notice.

I'm jumping to conclusions that it could be CFS related, and that would make sense for 2.6.24 too .... but I'm pretty much totally uninformed on that.