System load is a measure of processes in the run queue. These are 'runnable' proceses, which may not be running, generally because of blocked IO.
\r\n\r\nIn 'top' or 'ps aux', these will appear as processes with an 'R' state flag.
\r\n\r\nIf your system tends toward a high load average, you can modify your atd daemon's load average restriction with the '-l' flag. Modify this in the appropriate /etc/init.d/ (or /etc/rc.d/init.d) script, and restart the daemon. The default is 1.5, which may be too low on some system.
\r\n\r\nYou can also check for resource starvation -- most likely open files (lsof, fuser), possibly memory, user process table entries, and other resources.
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