System activity accounting via cron daemon
Two shell scripts (/usr/lib/sa/sa1 and /usr/lib/sa/sa2) are structured to be run by the cron daemon and provide daily statistics and reports.
The sar command calls a process named sadc to access system data. Sample stanzas are included (but commented out) in the /var/spool/cron/crontabs/adm crontab file to specify when the cron daemon should run the shell scripts.
The following lines show a modified crontab for the adm user. Only the
comment characters for the data collections were removed:
#=================================================================
# SYSTEM ACTIVITY REPORTS
# 8am-5pm activity reports every 20 mins during weekdays.
# activity reports every an hour on Saturday and Sunday.
# 6pm-7am activity reports every an hour during weekdays.
# Daily summary prepared at 18:05.
#=================================================================
0 8-17 * * 1-5 /usr/lib/sa/sa1 1200 3 &
0 * * * 0,6 /usr/lib/sa/sa1 &
0 18-7 * * 1-5 /usr/lib/sa/sa1 &
5 18 * * 1-5 /usr/lib/sa/sa2 -s 8:00 -e 18:01 -i 3600 -ubcwyaqvm &
#=================================================================Collection of data in this manner is useful to characterize system usage over a period of time and to determine peak usage hours.