# installation
# It collects the data every 10 minutes and generate its report daily. crontab file (/etc/cron.d/sysstat) is responsible for collecting and generating reports.
yum install sysstat
systemctl start sysstat
systemctl enable sysstat

# show CPU utilization 5 times every 2 seconds.
sar 2 5

# show memory  utilization 5 times every 2 seconds.
sar -r 2 5

# show paging statistics 5 times every 2 seconds.
sar -B 2 5

# To generate all network statistic:
sar -n ALL

# reading SAR log file using -f
sar -f /var/log/sa/sa31|tail