Monitoring Load & Memory using SAR

sar for load & memory.

sysstat - daemon 

Using sar we can monitor performance of server(load, memory etc…)in real time.

 

sar -q

report load average. (fetch data from /var/log/sa(sysstat)/sa*, where sa* represent the date like sa10,sa11,sa12etc.).

Examples,

sar -q  (List current day’s load averages starting from 12:00:00, with 10 minute interval).

sar -q 1 5 (List load averages 5 times from when we enter this with an interval of 1 sec).

sar -q -f /var/log/sa/sa23  (Fetch data from /var/log/sa/sa23).

sar -r 

report memory details.

Examples,

sar -r (List current days memory usage from 12:00:00)

sar -r 1 5 (List memory usage 5 times from when we enter this with an interval of 1 sec).

sar -r -f /var/log/sa/sa23  (Fetch data from /var/log/sa/sa23).

Examples,
1. sar -q




2. sar -q 1 5




3. sar -q -f /var/log/sysstat/sa06





4. sar -r




5. sar -r 1 5




6. sar -r -f /var/log/sysstat/sa06




-r and -q are the commonly using SAR switches, Please refer other switches too (-u, -v, -P, -d, -b etc…)