Home / server / Questions / 121963
In Process
dani.jtk
Asked: 2010-03-13 09:48:26 +0800 CST

can someone explain IOSTAT ouput?

  • 772

i'am having IBM server with Redhat 5 ElsmP connected to the IBM Storage over iSCSI (in sdb ) can someone explain this output from iostat command 

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
          12.79    0.01    4.53   72.22    0.00   10.45

Device:            tps   Blk_read/s   Blk_wrtn/s   Blk_read   Blk_wrtn
sda              95.63        48.88       240.95  485589164 2393706728
sdb              29.20       350.49       402.08 3481983365 3994494696

move large file to sdb very slowly,it seem normaly?

linux iostat

2 Answers

  1. The following articles will give you a better idea about iostat. I always use iostat -x .

    http://mituzas.lt/2009/03/11/iostat/

    http://www.igvita.com/2009/06/23/measuring-optimizing-io-performance/

    • 6

  2. It appears you have 72.22% iowait(time spent by a process while waiting for disk I/O to complete) which is likely why the file move is slow.

    • 1