pcp-nfsiostat - Man Page

Emulate iostat for NFS mount points using /proc/self/mountstats

Synopsis

pcp [pcp options] nfsiostat [-s samples] [-a archive] [-Z --timezone] [-z --hostzone] [-V Version]

Description

The pcp-nfsiostat command reports client-side Network File System (NFS) I/O statistics for each mounted NFS filesystem. For every NFS mountpoint, the output consists of a summary section followed by detailed read and write statistics blocks. These statistics include operation rates, data throughput, latency, retransmissions, queueing delays, and error counts. By default, pcp-nfsiostat monitors NFS mountpoints on the local host and reports live metrics collected via the PCP NFS PMDA. When an archive is specified, historical metrics are reported instead.

Output Format

Statistics are reported per mounted NFS filesystem using the following layout:

server:/export mounted on /mount/point:

           ops/s       rpc bklog
           0.017           0.000

read:              ops/s   kB/s   kB/op   retrans   avg RTT (ms)   avg exe (ms)   avg queue (ms)   errors
                   ...

write:             ops/s   kB/s   kB/op   retrans   avg RTT (ms)   avg exe (ms)   avg queue (ms)   errors
                   ...

Field Descriptions

ops/s

Number of NFS operations performed per second.

rpc bklog

Average number of RPC requests waiting to be transmitted.

kB/s

Kilobytes transferred per second.

kB/op

Average number of kilobytes transferred per operation.

retrans

Number of RPC retransmissions and the retransmission percentage.

avg RTT (ms)

Average round-trip time in milliseconds for RPC requests.

avg exe (ms)

Average execution time in milliseconds spent servicing requests on the server.

avg queue (ms)

Average time in milliseconds spent waiting in the RPC transmission queue.

errors

Number of failed operations and failure percentage.

Options

-a, --archive Iarchive

Fetch NFS I/O statistics from the specified PCP archive.

-s, --samples Isamples

Number of samples to collect before exiting.

-z,  --hostzone

Set the reporting timezone to the local timezone of the metrics source.

-Z, --timezone Itz

Set the reporting timezone.

-V,  --version

Display version information and exit.

-?,  --help

Display usage information and exit.

Notes

pcp-nfsiostat reports client-side NFS statistics collected from the kernel and exposed via the PCP NFS PMDA. The output format and metrics are similar to those reported by the nfsiostat(1) tool from the nfs-utils package.

PCP Environment

Environment variables with the prefix PCP_ are used to parameterize the file and directory names used by PCP. On each installation, the file /etc/pcp.conf contains the local values for these variables. The $PCP_CONF variable may be used to specify an alternative configuration file, as described in pcp.conf(5).

For environment variables affecting PCP tools, see pmGetOptions(3).

See Also

PCPIntro(1), pcp(1), nfsiostat(1), environ(7).

Info

PCP Performance Co-Pilot