Site performance, Server errors, outages and tunings

I am getting this a lot since yesterday. Trying the same addres again often works. I remember having read something about database troubles, but couldn't find it, so I wrote it here.

[Like Ra]

Capacity problem. As I said I will probably have to upgrade to the business model, but that will require some investments. See here: http://www.likera.com/blog/wp/archives/8836

[Like Ra]

Also we've reached another record today: 62 online users.

[Like Ra]

The site is running on a virtual server now. But after some time we are getting server error again. For some reason PHP processes get stuck. After reboot or after I manually kill the stuck processes, everything is back to normal.

I suspect one plugin I've currently disabled. Let's see if it gets better.

[Like Ra]

apparently it was the caching one w3-cache. Instead of increasing performance it hogged it. Took me quite a while to figure out what it was.


Let's try to reinstall it...

[Like Ra]

Reinstalled, reconfigured, crashed again.
Removed...

Fun, fun ...

[Like Ra]

Too many stuck PHP processes ... Does not look good. This is exactly what brings the system to a halt.

[Like Ra]

Still works... Meanwhile fixed another old error.

[Like Ra]

No, there is something else...

[Like Ra]

I don't get it ... I see no problems at all, but 15 min ago the load was 61!

top - 18:08:01 up 1:17, 2 users, load average: 46.63, 61.28, 41.59

So I had to reboot the VPS (again).