NFSIOSTAT(1) | Linux User's Manual | NFSIOSTAT(1) |
NAME¶
nfsiostat - Report input/output statistics for network filesystems (NFS).SYNOPSIS¶
nfsiostat [ -h ] [ -k | -m ] [ -t ] [ -V ] [ interval [ count ] ]DESCRIPTION¶
The nfsiostat command displays statistics about read and write operations on NFS filesystems.REPORT¶
The Network Filesystem (NFS) report provides statistics for each mounted network filesystem. Transfer rates are shown in 1K blocks by default, unless the environment variable POSIXLY_CORRECT is set, in which case 512-byte blocks are used. The report shows the following fields:This columns shows the hostname of the NFS
server followed by a colon and by the directory name where the network
filesystem is mounted.
rBlk_nor/s (rkB_nor/s, rMB_nor)
Indicate the number of blocks (kilobytes,
megabytes) read by applications via the read(2) system call interface. A block
has a size of 512 bytes.
wBlk_nor/s (wkB_nor/s, wMB_nor/s)
Indicate the number of blocks (kilobytes,
megabytes) written by applications via the write(2) system call interface.
rBlk_dir/s (rkB_dir/s, rMB_dir/s)
Indicate the number of blocks (kilobytes,
megabytes) read from files opened with the O_DIRECT flag.
wBlk_dir/s (wkB_dir/s, wMB_dir/s)
Indicate the number of blocks (kilobytes,
megabytes) written to files opened with the O_DIRECT flag.
rBlk_svr/s (rkB_svr/s, rMB_svr/s)
Indicate the number of blocks (kilobytes,
megabytes) read from the server by the NFS client via an NFS READ request.
wBlk_svr/s (wkB_svr/s, wMB_svr/s)
Indicate the number of blocks (kilobytes,
megabytes) written to the server by the NFS client via an NFS WRITE request.
ops/s
Indicate the number of operations that were
issued to the filesystem per second.
rops/s
Indicate the number of 'read' operations that
were issued to the filesystem per second.
wops/s
Indicate the number of 'write' operations that
were issued to the filesystem per second.
OPTIONS¶
- -h
- Make the NFS report easier to read by a human.
- -k
- Display statistics in kilobytes per second.
- -m
- Display statistics in megabytes per second.
- -t
- Print the time for each report displayed. The timestamp format may depend on the value of the S_TIME_FORMAT environment variable (see below).
- -V
- Print version number then exit.
ENVIRONMENT¶
The nfsiostat command takes into account the following environment variables:- S_TIME_FORMAT
- If this variable exists and its value is ISO then
the current locale will be ignored when printing the date in the report
header. The nfsiostat command will use the ISO 8601 format
(YYYY-MM-DD) instead. The timestamp displayed with option -t will also be
compliant with ISO 8601 format.
- POSIXLY_CORRECT
- When this variable is set, transfer rates are shown in
512-byte blocks instead of the default 1K blocks.
BUG¶
/proc filesystem must be mounted for nfsiostat to work.FILE¶
/proc/self/mountstats contains statistics for network filesystems.AUTHORS¶
Written by Ivana Varekova (varekova <at> redhat.com)SEE ALSO¶
sar(1), pidstat(1), mpstat(1), vmstat(8), iostat(1), cifsiostat(1)JANUARY 2011 | Linux |