cifsiostat
Report CIFS/SMB client statistics
SYNOPSIS
cifsiostat [options] [interval [count ]]
PARAMETERS
-c
Display requests per second (r/s, w/s) instead of throughput
-d
Display device utilization (%util) statistics
-h
Make report human readable (e.g., use GiB/s suffixes)
-k
Display rates in kilobytes per second (default)
-m
Display rates in megabytes per second
-t
Print timestamp beside each report
-V
Display version information and exit
interval
Seconds between reports (default: 1)
count
Number of reports (default: unlimited)
DESCRIPTION
cifsiostat is a command-line tool from the sysstat package that reports CIFS (Common Internet File System) statistics for network filesystems mounted via SMB/CIFS protocols, such as Samba shares. It provides detailed I/O performance metrics, helping administrators diagnose bottlenecks in file access over networks.
Primarily, it displays throughput for reads and writes (in KB/s or MB/s), transactions per second (tps), and data transferred per operation. Statistics are aggregated per CIFS server or share. Like other sysstat tools, it can run in single-shot mode for current stats or continuously with an interval (in seconds) and optional count of reports.
The tool reads data from /proc/fs/cifs/stats (or equivalent kernel interfaces), making it lightweight and kernel-dependent. Output includes columns like Svname (server name), tps, kB_read/s, kB_wrtn/s, and async/sync variants. It's invaluable for tuning Samba servers, monitoring NAS devices, or troubleshooting slow file transfers in enterprise environments.
Human-readable output with -h shows GiB/s, etc., and device utilization with -d adds %util metrics.
CAVEATS
Requires sysstat package and kernel CIFS stats enabled (CONFIG_CIFS_STATS=y). No output if no CIFS mounts active. Data from /proc/fs/cifs/ may reset on remounts. Not for local filesystems.
TYPICAL OUTPUT
Svname: Server name
tps: Transactions/sec
kB_read/s: KB read/sec
kB_wrtn/s: KB written/sec
%util: Device utilization (with -d)
EXAMPLE
cifsiostat 5 3
Reports CIFS stats every 5s, 3 times.
HISTORY
Part of sysstat suite since version 6.0.2 (2006), added for Linux kernel 2.6 CIFS support. Enhanced in later versions for better Samba integration and human-readable output (sysstat 10+). Maintained by Sebastien Godard.
