SAR (System Activity Reporter)
7. Display context switch per second (sar -w) in SAR (System Activity Reporter)
This reports the total number of processes created per second, and total number of context switches per second. “1 3″ reports for every 1 seconds a total of 3 times.
$ sar -w 1 3 Linux 2.6.18-194.el5PAE (dev-db) 03/26/2011 _i686_ (8 CPU) 08:32:24 AM proc/s cswch/s 08:32:25 AM 3.00 53.00 08:32:26 AM 4.00 61.39 08:32:27 AM 2.00 57.00
Following are few variations:
- sar -w
- sar -w 1 3
- sar -w -f /var/log/sa/sa10
8. Reports run queue and load average (sar -q) in SAR (System Activity Reporter)
This reports the run queue size and load average of last 1 minute, 5 minutes, and 15 minutes. “1 3″ reports for every 1 seconds a total of 3 times.
$ sar -q 1 3 Linux 2.6.18-194.el5PAE (dev-db) 03/26/2011 _i686_ (8 CPU) 06:28:53 AM runq-sz plist-sz ldavg-1 ldavg-5 ldavg-15 blocked 06:28:54 AM 0 230 2.00 3.00 5.00 0 06:28:55 AM 2 210 2.01 3.15 5.15 0 06:28:56 AM 2 230 2.12 3.12 5.12 0 Average: 3 230 3.12 3.12 5.12 0
Note: The “blocked” column displays the number of tasks that are currently blocked and waiting for I/O operation to complete.Following are few variations:
- sar -q
- sar -q 1 3
- sar -q -f /var/log/sa/sa10
9. Report network statistics (sar -n) in SAR (System Activity Reporter)
This reports various network statistics. For example: number of packets received (transmitted) through the network card, statistics of packet failure etc.,. “1 3″ reports for every 1 seconds a total of 3 times.
sar -n KEYWORD
KEYWORD can be one of the following:
- DEV – Displays network devices vital statistics for eth0, eth1, etc.,
- EDEV – Display network device failure statistics
- NFS – Displays NFS client activities
- NFSD – Displays NFS server activities
- SOCK – Displays sockets in use for IPv4
- IP – Displays IPv4 network traffic
- EIP – Displays IPv4 network errors
- ICMP – Displays ICMPv4 network traffic
- EICMP – Displays ICMPv4 network errors
- TCP – Displays TCPv4 network traffic
- ETCP – Displays TCPv4 network errors
- UDP – Displays UDPv4 network traffic
- SOCK6, IP6, EIP6, ICMP6, UDP6 are for IPv6
- ALL – This displays all of the above information. The output will be very long.
$ sar -n DEV 1 1 Linux 2.6.18-194.el5PAE (dev-db) 03/26/2011 _i686_ (8 CPU) 01:11:13 PM IFACE rxpck/s txpck/s rxbyt/s txbyt/s rxcmp/s txcmp/s rxmcst/s 01:11:14 PM lo 0.00 0.00 0.00 0.00 0.00 0.00 0.00 01:11:14 PM eth0 342.57 342.57 93923.76 141773.27 0.00 0.00 0.00 01:11:14 PM eth1 0.00 0.00 0.00 0.00 0.00 0.00 0.00
10. Report Sar (System Activity Reporter) Data Using Start Time (sar -s)
When you view historic sar data from the /var/log/sa/saXX file using “sar -f” option, it displays all the sar data for that specific day starting from 12:00 a.m for that day.Using “-s hh:mi:ss” option, you can specify the start time. For example, if you specify “sar -s 10:00:00″, it will display the sar data starting from 10 a.m (instead of starting from midnight) as shown below.You can combine -s option with other sar option.For example, to report the load average on 26th of this month starting from 10 a.m in the morning, combine the -q and -s option as shown below.
$ sar -q -f /var/log/sa/sa23 -s 10:00:01 Linux 2.6.18-194.el5PAE (dev-db) 03/26/2011 _i686_ (8 CPU) 10:00:01 AM runq-sz plist-sz ldavg-1 ldavg-5 ldavg-15 blocked 10:10:01 AM 0 127 2.00 3.00 5.00 0 10:20:01 AM 0 127 2.00 3.00 5.00 0 ... 11:20:01 AM 0 127 5.00 3.00 3.00 0 12:00:01 PM 0 127 4.00 2.00 1.00 0
There is no option to limit the end-time. You just have to get creative and use head command as shown below.For example, starting from 10 a.m, if you want to see 7 entries, you have to pipe the above output to “head -n 10″.
$ sar -q -f /var/log/sa/sa23 -s 10:00:01 | head -n 10 Linux 2.6.18-194.el5PAE (dev-db) 03/26/2011 _i686_ (8 CPU) 10:00:01 AM runq-sz plist-sz ldavg-1 ldavg-5 ldavg-15 blocked 10:10:01 AM 0 127 2.00 3.00 5.00 0 10:20:01 AM 0 127 2.00 3.00 5.00 0 10:30:01 AM 0 127 3.00 5.00 2.00 0 10:40:01 AM 0 127 4.00 2.00 1.00 2 10:50:01 AM 0 127 3.00 5.00 5.00 0 11:00:01 AM 0 127 2.00 1.00 6.00 0 11:10:01 AM 0 127 1.00 3.00 7.00 2