Monitoring CIFS File System I/O Performance with cifsiostat

Description: cifsiostat is a tool used to monitor the I/O performance of CIFS file systems.

Syntax:

cifsiostat [ options ] [ <interval> [ <count> ] ] [ mount point ]

Overview: cifsiostat is a tool for monitoring I/O performance of CIFS (Common Internet File System) file systems, similar to iostat. It is part of the sysstat package and is specifically designed to display I/O statistics for CIFS client mount points. CIFS is a network file-sharing protocol based on SMB (Server Message Block), commonly used in Windows environments but also supported by Linux and other operating systems.

Options:

• -k Show I/O activity statistics in kilobytes per second instead of blocks per second.
• -m Show I/O activity statistics in megabytes per second.

Parameters:

• Interval The time interval (in seconds) between each output.
• Count The total number of outputs.
• Mount Point Show I/O activity statistics for a specific mount point.

Examples:

1 Display I/O activity statistics for all CIFS mount points:

cifsiostat

2 Output statistics every 5 seconds for a total of 10 times:

cifsiostat 5 10

3 Show statistics for a specific mount point:

cifsiostat /mnt/cifs

4 View I/O statistics for two mount points:

cifsiostat /mnt/shared /mnt/backup

The output of cifsiostat is similar to iostat, including the number of read and write operations, the amount of data read and written, the average I/O size, and I/O wait times. An example output is shown below:

Example Output:

Filesystem: /mnt/cifs
rMB/s    wMB/s    rIO/s    wIO/s   rSizeKB   wSizeKB
0.000    0.012    1.00     10.00   0.00      4.00

Explanation of Fields:

rMB/s MB read per second.
wMB/s MB written per second.
rIO/s Number of read I/O requests per second.
wIO/s Number of write I/O requests per second.
rSizeKB Average size (in KB) of each read operation.
wSizeKB Average size (in KB) of each write operation.