Displaying vdisk I/O statistics
To display vdisk I/O statistics, run mmpmon with the following command included in the input file:
vio_s [f [rg RecoveryGroupName [ da DeclusteredArrayName [ v VdiskName]]]] [reset]This request returns strings containing vdisk I/O statistics as seen by that node. The values are presented as total values for the node, or they can be filtered with the f option. The reset option indicates that the statistics should be reset after the data is sampled.
If the -p option is specified when running mmpmon, the vdisk I/O statistics are provided in the form of keywords and values in the vio_s response. Table 1 lists and describes these keywords in the order in which they appear in the output.
| Keyword | Description |
|---|---|
| _n_ | The IP address of the node that is responding. This is the address by which IBM Storage Scale knows the node. |
| _nn_ | The name by which IBM Storage Scale knows the node. |
| _rc_ | The reason or error code. In this case, the reply value is 0 (OK). |
| _t_ | The current time of day in seconds (absolute seconds since Epoch (1970)). |
| _tu_ | The microseconds part of the current time of day. |
| _rg_ | The name of the recovery group. |
| _da_ | The name of the declustered array. |
| _v_ | The name of the disk. |
| _r_ | The total number of read operations. |
| _sw_ | The total number of short write operations. |
| _mw_ | The total number of medium write operations. |
| _pfw_ | The total number of promoted full track write operations. |
| _ftw_ | The total number of full track write operations. |
| _fuw_ | The total number of flushed update write operations. |
| _fpw_ | The total number of flushed promoted full track write operations. |
| _m_ | The total number of migrate operations. |
| _s_ | The total number of scrub operations. |
| _l_ | The total number log write operations. |
| _fc_ | The total number of force consistency operations. |
| _fix_ | The total number of buffer range fix operations. |
| _ltr_ | The total number of log tip read operations. |
| _lhr_ | The total number of log home read operations. |
| _rgd_ | The total number of recovery group descriptor write operations. |
| _meta_ | The total number metadata block write operations. |
To display these statistics, use the sample script /usr/lpp/mmfs/samples/vdisk/viostat. The following shows the usage of the viostat script:
viostat [-F NodeFile | [--recovery-group RecoveryGroupName
[--declustered-array DeclusteredArrayName
[--vdisk VdiskName]]]]
[Interval [Count]]