PHP/MySQL server started slowing down to unusable

[neonetman]

We have a PHP/MySQL IIS server running our Intranet on a combination of Joomla and in house code, which has been runnig with no issues for 2 years now. Over the last few days we are getting slow-downs to the point of non usable.

 

* Nothing has changed on the server

* It has plenty of both RAM and CPU allocated to it (it's a Hyper-V machine)

* It has plenty of disk space available

 

I suspect it is to do with the INNODB tables in the database (as one of our backend scripts running on an ISAM table seems fine), however despite increasing memory allocation and max connections to the MySQL server, I'm at a loss to know what is causing it.

 

Can anyone point me in the direction of where to look?

[Meldrew]

Do the mysql logs show anything unusual?

 

Meldrew

[neonetman]

No that I can see, but I'm no expert on MySQL