[FIXED][CRITICAL] DB Connection Issue

[Freiegeister]

I had a recent issue with SQL Server where the connection pool was exhausted faster than the garbage collection could add redundant connections back to the pool. The cause was tracked to a single db calling function that wasn't explicitly closing the connection.

Could this be the case with M/MU?

[sparrowhawk]

I don't think so. I'm pretty sure that I explicitely close all connections, but in any case as far as I understand it, either PHP or MySQL (not sure which bit handles it) does a database disconnection at the end of all scripts.

Anyone know wheter this is correct?

[Freiegeister]

I was doing some VB.Net/MYSQL programming over the weekend and hit the Too Many Connections error.
The problem? One of my helper classes was not explicitly closing the connection.

I wouldn't think it would be one of the core game modules, but possibly one of the other sections like "Member" or "Login" may be doing this in some situations.

[sparrowhawk]

OK, I'll go through the scripts again to see whether I've forgotten to do an explicit close anywhere.

Thanks.

[sparrowhawk]

Getting it yet again today .

However, as I was the only player on at the time (I think), I'm beginning to feel that it's not the scripts, although I'm not ruling that out as yet.

It also started happening after the UKlinux crash, but agian that may be unrelated.

Needle. Haystack. Proverbial.

[sparrowhawk]

OK, I think that I may have identified the problem. I have uploaded some updated scripts and hopefully that should solve the problems.

The site is unlikely to be active again for some time, until the connections are released again by the server. (Hours?)

[sparrowhawk]

OK, it's back sooner than expected. Hope the fixes work!

[sparrowhawk]

In fact, it's speeding along like a... a .... very fast thing ;D

BTW, David was right, I had some unclosed connections.

[sparrowhawk]

And now it's hanging again

My scripts or the server? I just don't know. The only way to find out will be to copy everything onto the icemark site and see if the problem persists.

Chris, let me know if/when you have time to run the MySQL upgrade script. I appreciate that this is low priority at the moment

Bugger. Here's the latest:

* The Web server may be down.
* The Web server may be too busy.
* The Web server may be experiencing other problems, preventing it from responding to clients.
* The communication path may be experiencing problems.

Nothing to do with connections this time.

Sigh...

[Freiegeister]

Happy to share what I learn from my own mistakes.


With the new problem, I always though Apache was good at recreating HTTP child processes as they got stomped on, unlike IIS that would probably need a restart if this happened.

This may be out of your control, as the HTTP connection pool would usually be shared with other web sites on the server. Let UKLinux know if it keeps happening as they should be able to check the logs to see which site is breaking connections.

[merlin]

Jean-Yves said:

And now it's hanging again

My scripts or the server? I just don't know. The only way to find out will be to copy everything onto the icemark site and see if the problem persists.

Chris, let me know if/when you have time to run the MySQL upgrade script. I appreciate that this is low priority at the moment

Bugger. Here's the latest:



Nothing to do with connections this time.

Sigh...

Email everything to me and I'll do it tonight, got no access to my home machine because of the builders! Alternatively email it to me at work and I can do it now.

[sparrowhawk]

Database has been sent. Please let me know when it's uploaded.

I'll upload the scripts in the meantime.

To the others:

PLEASE DO NOT LOGIN TO THE ICEMARK M/MU UNTIL I LET YOU KNOW THAT IT'S ALL OK!!!

Thanks!

[sparrowhawk]

So far so good from my end. Is it OK for everyone else?

[Matija]

Works great.

[Ringthane]

Oh yes ;D More games