[rhn-users] Random high load - bizzare fix

[Charith Perera]

Over the past few weeks, many of our machines running RHEL have been showing 
very high loads at random times. Some of the machines run Apache and postfix. 
The average load is usually around 0.5 on some machines and 0.0 on others. 
When the load spikes, it's usually around 3.0, and has reached 5.0 on some 
occations. We have tried turning off all services (NFS, NFS mounts, postfix, 
crond, etc) and Apache, none of which made any significant reduction in the 
load. 

On one occasion there were a few updates available for vim, cups, and cpio. 
Doing the updates fixed the load problem immediately, so I figured that the 
cpio may have had a problem. However, upon further inspection of the 
advisory, it seemed completely unrelated. 

On the most recent occurance of the load spike, I ran "up2date -l" and found 
that there were no updates available. However, immediately following the 
execution of the command, the load returned to the normal value. 

I am waiting to see if it works a third time. Until then, has anyone else 
experienced this? What could be raising the system load so high, and how does 
up2date fix the problem?

Thanks,


Charith Perera