mysql_pconnect: Too many connections error

agligich

My application is accessed my many users
So i am running application with persistance connection(mysql_pconnect)
I keep getting php warning: Too many connections and my db server goes down and I have to reboot db server to get application to work

I am running my aplication on Linux platform with Apache/1.3.33 PHP/4.3.11 MySQL/4.1.10a
I set max connections to 500
But the error still keeps appearing

Can anyone suggest anything?
Thanks a lot...

nemonoman

try not using pconnect.
try closing connections.

Roger_Ramjet

Basic fix is NOT to use mysql_pconnect, just use mysql_connect

There is no gain from using it except in certain very rare situations which demand it. Otherwise it just causes problems. The behaviour and use of pconnect is misunderstood by many people, and nearly always ends up with your problem.

This has been discussed in depth in these threads if you want to know why

http://www.phpbuilder.com/board/showthread.php?t=10292426&highlight=pconnect
http://www.phpbuilder.com/board/showthread.php?t=10292274&highlight=pconnect
http://www.phpbuilder.com/board/showthread.php?t=10291643&highlight=pconnect

agligich

tx
it was very usefull to read about pconnect
and proved me that i definatly need to stick to using it
i have seportate boxes for db and web servers and i have high traffic

Can u recomd anything to help me deal with this issue

nemonoman

Highly recommend you change to mysql_connect, close connections following db activities, and see if this doesn't instantly solve your problem.

agligich

i am more then sure that it will
but performance will go down and i can't affort that

nemonoman

You are beyond our help.

ahundiak

If you absolutely have to have more than 500 active connections then increase the max connections limit on your db server.

Seems like an awful lot though. Must have a pretty powerful db server. You do understand that each time a page is accessed it probably gets a different connection? The performance improvement that you think you are getting is probably insignificant.

Also, consider the difference in performance bewteen a working system and a non-working system.

Roger_Ramjet

agligich wrote:
tx
it was very usefull to read about pconnect
and proved me that i definatly need to stick to using it
i have seportate boxes for db and web servers and i have high traffic

Can u recomd anything to help me deal with this issue

You have misunderstood what you read. Not unusual, I did myself at first, and most people do. That was why I pointed you to our discussions on this issue.

persistent connections are NOT closed when you use mysql_close(), they are only killed when you restart the server. (which is why you currently have to keep restarting it to keep your app running) AND THERE IS NO WAY ROUND THIS
they are not pooled for other processes to use, they are only reused if the very same process, NOT SCRIPT BUT INSTANCE OF THAT SCRIPT, needs to reconnects - unlikely to actually happen with a web app.
this means that you end up with a whole load of running connections that are not being used, nor can they be used since the web server process that created them no longer exists.
so you hit your max connections limit - and will do however big you make it - cos you cannot make it infinite

Persistent connections would be of value if you had a server script permanently running to e.g. mirror you db, log transactions, or process something for client scripts; since that process would still have the same identity every time it needed to use a db connection and so would get the benefit of pconnect.