[8088]

Nothing wrong with the load then. Are you sure those values were actual at the moment your server was lagging? Also, keep an eye on top or htop (press 1 to see all CPU cores) to see if it's HLDS or another process consuming so much CPU time.

[modernatur]

Yeah it's when the server getting freeze lag, and it's the hlds that consuming cpu time. All other process is running fine.

[Firewall_]

you install centos 5.9 . Dynamic tick kernel like high cpu usage for hlds.