Re: connection pool

Hallo

Need your help

1 got a Site runnig php 4.4.2 and postgresql (8.1.4) and
Follwing problem

- 4 Server (Apache) up to 300 clients connection to the DB
- 1 DB machine

So:

- If I run with persisent, i got up to 1200 Connction and I run out
of memeory

- if I run with no persisent connection i got massive forking of postgres
(but less problems)

How can I build up a Pool of Connections ?

What about "Pgpool" ?

Thanks

Hi,

I had the same trouble 6 years ago with my beginning of Postgresql ...

4 web and 1 db ...

Just put a limitation in the php.ini

; Maximum number of persistent links. -1 means no limit.
pgsql.max_persistent = 18

; Maximum number of links (persistent+non persistent). -1 means no limit.
pgsql.max_links = 18

It'll run perfectly ... for me it's like that since 6 years ... and I have
thousand of visitor each day on my services :o)

Regards,

Le lundi 31 juillet 2006 21:48, Peter Hofer a écrit :
> Hallo
>
> Need your help
>
> 1 got a Site runnig php 4.4.2 and postgresql (8.1.4) and
> Follwing problem
>
> - 4 Server (Apache) up to 300 clients connection to the DB
> - 1 DB machine
>
> So:
>
> - If I run with persisent, i got up to 1200 Connction and I run out
> of memeory
>
> - if I run with no persisent connection i got massive forking of postgres
> (but less problems)
>
> How can I build up a Pool of Connections ?
>
> What about "Pgpool" ?
>
> Thanks
>
>
>
>
>
>
>
>
>
>
>
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 5: don't forget to increase your free space map settings

--
Hervé Piedvache

NOUVELLE ADRESSE - NEW ADDRESS :
Elma Ingénierie Informatique
3 rue d'Uzès
F-75002 - Paris - France
Pho. 33-144949901
Fax. 33-144882747

Hy

Thanks for your answer

As far as i know " pgsql.max_persistent " limits the no on
Persistent Connections per apache client - and not for all
Apaches - so I set it "pgsql.max_persistent = 1" since we
Connect to the same DB all the time

Currently we got 2 Servers runnung with persistent Connection,
and 2 Server with non-persitent connections

Right now i have 359 progres running, 345 are idle.

If I set the other servers to persistent connections, too, I will have
About 700 progres running - 95% on idle
They all take memory ...

I will have to expand up to 10 and more WebServers in near future
Therefore persistent-Connection (because of the memory amount to handle 1500
Connection) nor
Non-persistent-Connection (because of forking ) is a suitable way

What I think about, is a maschine getting all the Connections from the
Apache, and
Forward only those to the DB whitch are not idle

Any idea ?

Thanks

Peter

> -----Ursprüngliche Nachricht-----
> Von: pgsql-php-owner(at)postgresql(dot)org
> [mailto:pgsql-php-owner(at)postgresql(dot)org] Im Auftrag von Hervé Piedvache
> Gesendet: Dienstag, 01. August 2006 09:29
> An: pgsql-php(at)postgresql(dot)org; peter(dot)hofer(at)ics(dot)at
> Betreff: Re: [PHP] connection pool
>
> Hi,
>
> I had the same trouble 6 years ago with my beginning of Postgresql ...
>
> 4 web and 1 db ...
>
> Just put a limitation in the php.ini
>
> ; Maximum number of persistent links. -1 means no limit.
> pgsql.max_persistent = 18
>
> ; Maximum number of links (persistent+non persistent). -1
> means no limit.
> pgsql.max_links = 18
>
> It'll run perfectly ... for me it's like that since 6 years
> ... and I have thousand of visitor each day on my services :o)
>
> Regards,
>
> Le lundi 31 juillet 2006 21:48, Peter Hofer a écrit :
> > Hallo
> >
> > Need your help
> >
> > 1 got a Site runnig php 4.4.2 and postgresql (8.1.4) and Follwing
> > problem
> >
> > - 4 Server (Apache) up to 300 clients connection to the DB
> > - 1 DB machine
> >
> > So:
> >
> > - If I run with persisent, i got up to 1200 Connction and I run out
> > of memeory
> >
> > - if I run with no persisent connection i got massive
> forking of postgres
> > (but less problems)
> >
> > How can I build up a Pool of Connections ?
> >
> > What about "Pgpool" ?
> >
> > Thanks
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> >
> > ---------------------------(end of
> > broadcast)---------------------------
> > TIP 5: don't forget to increase your free space map settings
>
> --
> Hervé Piedvache
>
> NOUVELLE ADRESSE - NEW ADDRESS :
> Elma Ingénierie Informatique
> 3 rue d'Uzès
> F-75002 - Paris - France
> Pho. 33-144949901
> Fax. 33-144882747
>
> ---------------------------(end of
> broadcast)---------------------------
> TIP 4: Have you searched our list archives?
>
> http://archives.postgresql.org

On Monday 31 July 2006 15:48, Peter Hofer wrote:
> Hallo
>
> Need your help
>
> 1 got a Site runnig php 4.4.2 and postgresql (8.1.4) and
> Follwing problem
>
> - 4 Server (Apache) up to 300 clients connection to the DB
> - 1 DB machine
>
> So:
>
> - If I run with persisent, i got up to 1200 Connction and I run out
> of memeory
>

one recommendation would be to set your max # of apache children to something
less than the amount of connections you can handle on postgresql. for
example, if you can only handle 1000 connections, set the max # of children
per server to say 245 (leave 20 slots for super user connections).

one thing I do wonder about is just how much ram (or how little) you have
available. istm 1200 connections should not run you out of memory on a
dedicated db machine.

> - if I run with no persisent connection i got massive forking of postgres
> (but less problems)
>

yeah... I often recommend not using persistent connections in php since they
tend to cause trouble :-)

> How can I build up a Pool of Connections ?
>
> What about "Pgpool" ?
>

RIght... pgpool basically acts as an intermediary, so everything connects to
the pool, which then forwards on requests to the database. I would think
reducing the number of apache children would work better, but this might be
worth a shot since your mixing pg_connect and pg_pconnect between servers. If
you do please report back your experience to the list :-)

--
Robert Treat
Build A Brighter LAMP :: Linux Apache {middleware} PostgreSQL