Changing the request histogram facility request size and latency ranges
The rhist nr (new range) request allows the user to change the size and latency ranges used in the request histogram facility.
The use of rhist nr implies an rhist reset. Counters for read and write operations are recorded separately. If there are no mounted file systems at the time rhist nr is issued, the request still runs. The size range operand appears first, followed by a blank, and then the latency range operand.
Table 1 describes the keywords for the rhist nr response, in the order that they appear in the output. These keywords are used only when mmpmon is invoked with the -p flag.
| Keyword | Description |
|---|---|
| _n_ | IP address of the node responding. This is the address by which GPFS knows the node. |
| _nn_ | The hostname that corresponds to the IP address (the _n_ value). |
| _req_ | The action requested. In this case, the value is nr. |
| _rc_ | Indicates the status of the operation. |
| _t_ | Indicates the current time of day in seconds (absolute seconds since Epoch (1970)). |
| _tu_ | Microseconds part of the current time of day. |
An _rc_ value of 16 indicates that the histogram operations lock is busy. Retry the request.