Difference between revisions of "I/O sniffing"

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imported>ThorstenStaerk
imported>ThorstenStaerk
Line 4: Line 4:
  
 
  # blktrace -d /dev/sdg -o - | blkparse -i -  
 
  # blktrace -d /dev/sdg -o - | blkparse -i -  
  <abbr title="device (major/minor number)">8,96</abbr>  <abbr title="device (major/minor number)">2</abbr>        <abbr title="device (major/minor number)">1</abbr>    <abbr title="device (major/minor number)">0.000000000</abbr>  <abbr title="device (major/minor number)">1236</abbr> <abbr title="device (major/minor number)">G</abbr>  <abbr title="device (major/minor number)">N</abbr> <abbr title="process">[kworker/2:4]</abbr>
+
  [...]
  8,96  2        2    0.000001308  1236  I  N 0 (00 ..) [kworker/2:4]
 
  8,96  2        3    0.000002781  1236  D  N 0 (00 ..) [kworker/2:4]
 
 
 
 
 
 
   <abbr title="device (major/minor number)">8,96</abbr>  <abbr title="processor">7</abbr>      <abbr title="sequence number">106</abbr>    <abbr title="timestamp">0.373952974</abbr> <abbr title="PID">11364</abbr>  <abbr title="Event">D</abbr>  <abbr title="Action">W</abbr> <abbr title="starting block + blocks">0 + 8</abbr> <abbr title="process">[kworker/7:2]</abbr>
 
   <abbr title="device (major/minor number)">8,96</abbr>  <abbr title="processor">7</abbr>      <abbr title="sequence number">106</abbr>    <abbr title="timestamp">0.373952974</abbr> <abbr title="PID">11364</abbr>  <abbr title="Event">D</abbr>  <abbr title="Action">W</abbr> <abbr title="starting block + blocks">0 + 8</abbr> <abbr title="process">[kworker/7:2]</abbr>
 
   8,96  7      107    0.374456639    47  C  W 0 + 8 [0]
 
   8,96  7      107    0.374456639    47  C  W 0 + 8 [0]

Revision as of 05:27, 25 May 2013

You can do I/O sniffing using the command blktrace. blktrace will show you every request that goes to the disk.

Example:

# blktrace -d /dev/sdg -o - | blkparse -i - 
[...]
  8,96   7      106     0.373952974 11364  D   W 0 + 8 [kworker/7:2]
  8,96   7      107     0.374456639    47  C   W 0 + 8 [0]