System information

16 System Analysis and Tuning Guide
16:28:51 scd0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
16:28:51 DEV tps rd_sec/s wr_sec/s avgrq-sz avgqu-sz await svctm %util
16:29:01 sdc 32.47 876.72 647.35 46.94 0.33 10.20 3.67 11.91
16:29:01 scd0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
16:29:01 DEV tps rd_sec/s wr_sec/s avgrq-sz avgqu-sz await svctm %util
16:29:11 sdc 48.75 2852.45 366.77 66.04 0.82 16.93 4.91 23.94
16:29:11 scd0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
16:29:11 DEV tps rd_sec/s wr_sec/s avgrq-sz avgqu-sz await svctm %util
16:29:21 sdc 13.20 362.40 412.00 58.67 0.16 12.03 6.09 8.04
16:29:21 scd0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
Average: DEV tps rd_sec/s wr_sec/s avgrq-sz avgqu-sz await svctm %util
Average: sdc 24.26 903.52 509.12 58.23 0.30 12.49 4.68 11.34
Average: scd0 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00
If your machine uses multiple disks, you will receive the best performance, if I/O re-
quests are evenly spread over all disks. Compare the Average values for tps, rd_sec/s,
and wr_sec/s of all disks. Constantly high values in the svctm and %util columns could
be an indication that the amount of free space on the disk is insufficient.
Network Statistics Reports: sar -n KEYWORD
The option -n lets you generate multiple network related reports. Specify one of the
following keywords along with the -n:
• DEV: Generates a statistic report for all network devices
• EDEV: Generates an error statistics report for all network devices
• NFS: Generates a statistic report for an NFS client
• NFSD: Generates a statistic report for an NFS server
• SOCK: Generates a statistic report on sockets
• ALL: Generates all network statistic reports
2.1.2.3 Visualizing sar Data
sar reports are not always easy to parse for humans. kSar, a Java application visual-
izing your sar data, creates easy-to-read graphs. It can even generate PDF reports.
kSar takes data generated on the fly as well as past data from a file. kSar is licensed
under the BSD license and is available from http://ksar.atomique.net/.