How to lowering server load when using SUPHP?

Had to uninstall eaccelerator and now server loads are through the roof!

[brizad]

I just added suphp to my VPS and my server loads have gone through the roof. I had heard there was some overhead when using suphp but I had no idea it would be so high--sometimes 100s of times higher than before.

I didn't find out until after the fact that eaccelerator wasn't compatible with suphp.

I've got 100 sites or so on my server and all but a few are wordpress and joomla so it's pretty php intensive.

I haven't been able to find any options for lowering the server load other than adding caching plugins to WP and joomla and hoping that it lowers the loads. But I'm hoping the WebmasterWorld geniuses might have some ideas ;)

Thanks!

[lammert]

Suphp switches user contexts between the different script calls which adds extra overhead. Furthermore switching user contexts may disable some of the system cache sharing functionality, which will cause more instances of the same data stored in memory, lowering the available space for general caching.

Are all 100 sites running under different user accounts, or are the site grouped with just a few different owners?

[brizad]

Lammert, yes all sites run under different accounts.

Turns out that when I ran suphp last week something else apparently got messed up that caused the server and memory loads to spike. Rebooting the server got things working much better. I started running suphp again today and so far the loads are not a whole lot higher than without suphp so maybe things will work out.

I'm definitely open to hearing about any ways to lower the load if possible.