ioztat
—
display logical I/O statistics for ZFS datasets
ioztat |
[-DeHINnoSxyz ] [-c
count] [-i
interval] [-T
u|d] [-s
name|operations|reads|writes|throughput|nread|nwritten]
[dataset ...] [interval
[count]] |
The ioztat
utility displays logical I/O statistics for
individual ZFS datasets. The first report is averaged over the system uptime
unless suppressed with -y
. If an
interval is specified, this is followed by reports
averaged over the reporting interval. If
-y
or a count is specified,
interval defaults to one second.
Underlying device I/O depends on pool and dataset configuration.
See
zpool-iostat(8)
and
iostat(8)
for reporting on these values.
To filter output you may pass in a list of datasets. If no
datasets are specified, statistics for every mounted dataset in the system
are shown. If the -n
option is given, child datasets
are not included for any specified dataset unless they are also directly
specified.
The options are as follows:
-D
- Display formatted byte sizes using decimal powers of 1000 instead of
powers of 1024.
-c
- Display count reports and exit. This can also be
specified after an interval at the end of the
argument list. If interval is specified but not
count then it defaults to infinity, otherwise it
defaults to one.
-e
- Display exact values, without truncating dataset names (unless
-p
is given) or formatting numeric output.
-H
- Scripted mode, skip headers and tab-separate fields instead of using
arbitrary whitespace.
-h
,
--help
- Display help text and exit.
-I
- Display total statistics since the last report instead of averages
per-second.
-i
- Pause interval seconds between reports. This can
also be specified at the end of the argument list, prior to an optional
count. If no interval is
specified the default is 1 second.
The ioztat
command will accept
non-integer intervals, but it should be noted the reporting interval is
not exact.
-N
- Display headers only once, instead of periodically repeating them.
-n
- Omit children of any specified datasets that haven't themselves been
explicitly specified.
-o
- Overwrite mode. Before each report, clear the screen and print only as
many lines as will fit.
-P
- Display dataset names on a single line.
-p
- Display dataset names as an indented tree spread across multiple lines.
These options override defaults that may be applied by different sorting
and display modes.
-S
- Sum child dataset statistics into their parents. This can be useful when
combined with
-n
to omit display of child datasets
while still seeing associated I/O.
-s
- Sort each report by the specified order. Defaults to
name.
-T
u|d
- Before each report, display a timestamp. Specify u
for a numeric Unix timestamp in seconds since the epoch, or
d for a formatted date-time.
-V
,
--version
- Display the current version of
ioztat
and
exit.
-x
- Specified once, display an opsize group containing throughput divided by
operations, giving the average byte size of each I/O. Specified twice,
also display an unlinks section giving a count of the number of files and
directories queued for deletion, and the number which have been
deleted.
-y
- Omit statistics since boot. This suppresses output for the first
interval seconds.
-z
- Omit datasets which have no activity.
ioztat rpool/USERDATA 1
Display per-second statistics for any mounted datasets within
rpool/USERDATA.
ioztat -zoTd -s operations
5
Display statistics for all mounted datasets with activity across
five second intervals, ordered by total read and write operations, limited
by available display and overwriting prior reports in a manner similar to
top(1).
ioztat -SIn rpool
Display sum total of I/O for all datasets within rpool since
boot.
ioztat -Hey
Display a single one-second report for all mounted datasets, using
a machine-readable format omitting headers, using tab-delimited fields, and
providing exact values.
Please report any issues at https://github.com/jimsalterjrs/ioztat/issues