[Asterisk-Users] (unexplicable) peaks of machine load

[Simone Cittadini]

I have strange peaks of machine load on my asterisk servers, looking at 
top the load is very high even if cpu usage is low and no swap memory is 
used.

This happens on all the machines, some of them have asterisk, mysql, agi 
and digium cards on them, so I thought I was only asking too much, but 
yesterday I noticed the same behaviour on an asterisk machine with only 
two digium in it, no other service and a two line extension.
I thought it can be a problem with digium cards but the interrupts 
aren't shared, and I have the same problem on a pure-voip server.

Asterisk version varies from 1.2.1 to 1.2.5, the kernels are 2.4 or 2.6 
(right ones for the installed cpu, not generic 386)
The only things in common are :

Linux debian, iax channels are used, with jitterbuffer

When this "ghost load" becomes too high (> 3) asterisk starts losing 
packets, and the users starts losing patience ...

Anyone experiencing a similar problem ?