Re: PGBOUNCER ISSUE PLEASE HELP(Slowing down the site)

Here is the output of OS limits

postgres(at)symds-pg:~ $ ulimit -a

core file size (blocks, -c) 0
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 790527
max locked memory (kbytes, -l) 32
max memory size (kbytes, -m) unlimited
open files (-n) 4096
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 10240
cpu time (seconds, -t) unlimited
max user processes (-u) 16384
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited

Thanks
Prabhjot

-----Original Message-----
From: ktm(at)rice(dot)edu [mailto:ktm(at)rice(dot)edu]
Sent: Thursday, June 18, 2015 10:16 AM
To: Sheena, Prabhjot
Cc: pgsql-performance(at)postgresql(dot)org; pgsql-general(at)postgresql(dot)org
Subject: Re: [PERFORM] PGBOUNCER ISSUE PLEASE HELP(Slowing down the site)

On Thu, Jun 18, 2015 at 05:09:10PM +0000, Sheena, Prabhjot wrote:
> Guys
> I have an issue going on with PGBOUNCER which is slowing down
> the site
>
> PGBOUNCER VERSION: pgbouncer-1.5.4-2.el6 (Hosted on separate machine) (16 cpu) 98GB RAM
> DATABASE VERION: postgresql 9.3
>
> When the total client connections to pgbouncer are close to 1000, site application works fine but when the total client connections crosses 1150 site application starts showing slowness.
>
> Here is an example of output
>
> postgres(at)symds-pg:~ $ netstat -atnp | grep 5432 | wc (Not all
> processes could be identified, non-owned process info will not be
> shown, you would have to be root to see it all.)
> 960 6720 104640
>
>
> As you can see total connections are like 960 right now my site application is working fine. When connections crosses 1150 and even though I see lot of available connections coz my default_pool_size is set high to 250 but still the application gets slow. Database performance on the other end is great with no slow running queries or anything. So the only place I can think the issue is at PGBOUNCER end.
>

Hi Prabhjot,

This is classic behavior when you have a 1024 file limit. When you are below that number, it work fine. Above that number, you must wait for a connection to close and exit before you can connect which will cause a delay. See what ulimit has to say?

Regards,
Ken