plan9 man page for iostats

IOSTATS(4)						     Kernel Interfaces Manual							IOSTATS(4)

NAME
       iostats - file system to measure I/O

SYNOPSIS
       iostats cmd [ args...  ]

DESCRIPTION
       Iostats is a user-level file server that interposes itself between a program and the regular file server, which allows it to gather statis-
       tics of file system use at the level of the Plan 9 file system protocol, 9P.  After a program exits a report is printed on standard error.

       The report consists of three sections.  The first section reports the amount of user data in read and write messages sent  by  the  program
       and  the  average  rate	at which the data was transferred.  The protocol line reports the amount of data sent as message headers, that is,
       protocol overhead.  The rpc line reports the total number of file system transactions.

       The second section gives the number of messages, the fastest, slowest, and average turn around time and the amount of  data  involved  with
       each 9P message type.  The final section gives an I/O summary for each file used by the program in terms of opens, reads and writes.

SOURCE
       /sys/src/cmd/iostats

BUGS
       Poor clock resolution means that large amounts of I/O must be done to get accurate rate figures.

       Can be fooled by programs that do fresh mounts outside its purview.

																	IOSTATS(4)