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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?

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thks Kyle for editing i'm beginer :) i'am verry appreciate that :) – dani.jtk Mar 12 '10 at 18:17

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

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Good example why "read the docs" is rarely an acceptable answer. Very little explained in those links. For example: What is TPS? – DraxDomax May 5 at 14:52

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.

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sdb mounted to IBM external Storage over iscsi and we have cronjob to move file from sda to sdb – dani.jtk Mar 12 '10 at 18:25
You need to look at the IBM external storage stats. That's where the bottleneck appears to be. – xenny Mar 26 '10 at 15:25

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