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nfsiostat manual page
NAMEnfsiostat - Report input/output statistics for network filesystems (NFS).
SYNOPSISnfsiostat [ -h ] [ -k | -m ] [ -t ] [ -V ] [--debuginfo] [ interval [ count ] ]
DESCRIPTIONThe nfsiostat command displays statistics about read and write operations on NFS filesystems.
The interval parameter specifies the amount of time in seconds between each report. The first report contains statistics for the time since system startup (boot). Each subsequent report contains statistics collected during the interval since the previous report. A report consists of an NFS header row followed by a line of statistics for each network filesystem that is mounted. The count parameter can be specified in conjunction with the interval parameter. If the count parameter is specified, the value of count determines the number of reports generated at interval seconds apart. If the interval parameter is specified without the count parameter, the nfsiostat command generates reports continuously.
REPORTThe 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:
Filesystem: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_dir/s (rkB_dir/s, rMB_dir/s)Indicate the number of blocks (kilobytes, megabytes) read from 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.
ops/sIndicate the number of operations that were issued to the filesystem per second.
rops/sIndicate the number of "read" operations that were issued to the filesystem per second.
wops/sIndicate the number of "write" operations that were issued to the filesystem per second.
--debuginfoPrint debug output to stderr.
-hMake the NFS report easier to read by a human.
-kDisplay statistics in kilobytes per second.
-mDisplay statistics in megabytes per second.
-tPrint the time for each report displayed. The timestamp format may depend on the value of the S_TIME_FORMAT environment variable (see below).
-VPrint version number then exit.
ENVIRONMENTThe iostat command takes into account the following environment variables:
S_TIME_FORMATIf 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.
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.
AUTHORSWritten by Ivana Varekova (varekova <at> redhat.com)
Maintained by Sebastien Godard (sysstat <at> orange.fr)
SEE ALSOsar(1), mpstat(1), pidstat(1), vmstat(8), iostat(1), cifsiostat(1)