ZILSTAT(1)

NAME
zilstat - report ZFS Intent Log statistics

SYNOPSIS
zilstat [-v] [-a|-p pool|-d dataset[,dataset…]] [-f field[,field…]] [-s separator] [-i interval]

DESCRIPTION
zilstat prints statistics about the ZFS Intent Log (ZIL). The ZIL is used to log synchronous write operations and is replayed on pool import if the system crashes before those writes are committed to the main pool.

By default, global ZIL statistics are displayed. When a pool or dataset is specified, per-dataset statistics are shown instead.

If an interval is specified, the output is repeated every interval seconds showing the change in values since the previous sample. Without an interval, cumulative values are displayed.

The following fields are available:
time
    Current time
pool
    Pool name
ds  Dataset name
obj Objset ID
cc  Commit count
cwc Commit writer count
cec Commit error count
csc Commit stall count
cSc Commit suspend count
cCc Commit crash count
ic  In-transaction count
iic Indirect in-transaction count
iib Indirect in-transaction bytes
icc Copied in-transaction count
icb Copied in-transaction bytes
inc Needcopy in-transaction count
inb Needcopy in-transaction bytes
idc Direct (copied + needcopy) count
idb Direct (copied + needcopy) bytes
iwc Total write (indirect + direct) count
iwb Total write (indirect + direct) bytes
imnc
    Normal metaslab count
imnb
    Normal metaslab bytes
imnw
    Normal metaslab write bytes
imna
    Normal metaslab alloc bytes
imsc
    SLOG metaslab count
imsb
    SLOG metaslab bytes
imsw
    SLOG metaslab write bytes
imsa
    SLOG metaslab alloc bytes
imc Total metaslab (normal + SLOG) count
imb Total metaslab (normal + SLOG) bytes
imw Total metaslab (normal + SLOG) write bytes
ima Total metaslab (normal + SLOG) alloc bytes
se% Space efficiency percentage (bytes / alloc)
sen%
    Normal space efficiency percentage
ses%
    SLOG space efficiency percentage
te% Total efficiency percentage (bytes / write)
ten%
    Normal total efficiency percentage
tes%
    SLOG total efficiency percentage

OPTIONS

-h  Display a help message.

-a  Print statistics for all datasets across all pools.

-d dataset
    Print statistics for the specified dataset(s). Multiple datasets may be given as a comma-separated list.

-f field
    Display only the specified fields. Multiple fields may be given as a comma-separated list. See DESCRIPTION for available fields.

-i interval
    Print statistics every interval seconds. Values are reported as rates per second.

-p pool
    Print statistics for all datasets in the specified pool.

-s separator
    Override the default field separator (two spaces) with a custom string.

-v  List all available field headers and their definitions.

ENVIRONMENT

Linux
    Statistics are read from /proc/spl/kstat/zfs/zil for global stats and from per-pool objset files under /proc/spl/kstat/zfs/pool/.

FreeBSD
    Statistics are read via sysctl(8) from the kstat.zfs tree.

SEE ALSO
zarcstat(1), zpool-status(8)

AUTHORS
This manual page was written by Christos Longros <chris.longros@gmail.com>.