Question about Solaris and sar

Discussion in 'OT Technology' started by trouphaz, Sep 4, 2008.

  1. trouphaz

    trouphaz New Member

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    I have a host that is running Solaris 10 and using mpxio for disk multipathing. When I run "sar -d" I see each device multiple times and I'm trying to understand what this stuff means. Here is a sample:

    Code:
    00:00:04   device        %busy   avque   r+w/s  blks/s  avwait  avserv
               ssd87.t3          0     0.0     334    6036     0.0     0.0
               ssd87.t4          0     0.0     335    6340     0.0     0.0
               ssd87.t7          0     0.0     334    7072     0.0     0.0
               ssd87.t8          0     0.0     335    6484     0.0     0.0
               ssd87             4     0.0       4      85     0.0     9.1
               ssd87,c           0     0.0       0       0     0.0     0.0
               ssd87,d           0     0.0       0       0     0.0     0.0
               ssd87,e           4     0.0       4      85     0.0     9.1
    
    Now, I know the ssd87,c, ssd87,d and ssd87,e entries each represent the slices on disk (a=0, b=1, c=2, etc). Since this is a VxVM disk, slice 4 is basically where all of the data is, slice 3 just has the VxVM headers and slice 2 is still the whole disk. Then, ssd87 on its own represents the entire disk.

    Through some deductive reasoning, I'm making an educated guess that the .t3, .t4, .t7 and .t8 entries represent the 4 paths to disk as managed by mpxio, but I can't seem to figure out the statistics associated with those paths. Is it saying i'm getting ~335 IOs/second per path and 6000-7000 blocks/sec per path? How come those numbers are completely different from the ssd87 entry for the same exact time period which is showing 4 IOs/sec and 85 blocks/sec?
     

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