slow page load and mysql errors

[dot2004]

Hi there - I've got three sites running Nuke 5.6 -- for the last month we've had reccuring instances where the pages take so long to load the server times out. Our server hosts did some looking at the mysql error logs and said their seems to be a problem with the way nuke is sending out the mysql queries and it overloads the server.
Does this sound familiar to anyone and do you have any suggestions?
I realize we need to upgrade to a newer version of PHP Nuke but I don't have the option of doing that until after the New Year -- this is our big selling season and we need the sites to be up!
Thanks for any help

[downsize]

first obvious question: did your host upgrade or make changes to mysql by chance?

second, any new or modified modules added?

third, does your host have 'log slow queries' enabled for mysql so you can isolate which ones are causing the problems?

maybe you need to rebuild your indexes.

does this happen randomly or during certain time periods throughout the day?

i'm still running 5.6 for many sites and do not have problems (using mysql v3.x)