Re: Connection pooling

On Sat, 08 Sep 2007 19:28:52 +0400, Scott Marlowe
<scott(dot)marlowe(at)gmail(dot)com> wrote:

> On 9/7/07, Max Zorloff <zorloff(at)gmail(dot)com> wrote:
>> On Fri, 07 Sep 2007 10:58:36 +0400, Marko Kreen <markokr(at)gmail(dot)com>
>> wrote:
>>
>> >> The pgpool (I tried 3.1, 3.4 and pgpool-II 1.2) works fine but has
>> the
>> >> following problem - after some time it
>> >> just "hangs", and if I try to connect to it with psql it just hangs
>> >> indefinitely. After restart
>> >> it works fine again. I turned off persistent connections in php so
>> it's
>> >> not that. Does anybody
>> >> have the same problem?
>> >
>> > All symptoms point to the same problem - your app fails to
>> > release server connections for reuse.
>> >
>> > If the problem is that PHP fails to disconnect connection,
>> > although the transaction is finished, you could run pgbouncer
>> > in more relaxed mode - pool_mode=transaction. Also setting
>> > client_idle_timeout to something may help debugging.
>>
>> > If the problem is uncommitted transactions, you could set
>> > query_timeout to some small number (1-3) to see where
>> > errors appear.
>> >
>> > Both timeouts are not something I would put into productions
>> > config, so the code should be fixed still...
>>
>> pgbouncer does not have this problem, only pgpool does.
>> pgbouncer has the problem of being very slow.
>>
>> i thought php released connections at the end of script?
>> and also if i had this problem pgpool would hang in a few seconds
>> because the server has some load.
>
> It does if you're running without pg_pconnect (i.e. using regular
> pg_connects) and if the script doesn't crash the apache/php backend
> it's running in.
>
> Are you using pg_pconnect and / or having crashing apache backends?

I specifically turn off pconnects and I don't think I crash backends,
never saw mistakes of that type.