Linux: Sysstat (sar)

The sar utility which is use monitor the history system performance data on your system.

To use the sar command, simply enter sar from the system,

# sar

To check the memory statistic,

# sar -r

To check the disk statistic,

# sar -d

To check network statistic,

# sar -n

To check processor statistic,

# sar -P ALL

To check certain date statistic let say 8th of the month

# sar -f /var/log/sa/sar09