xsm

xsm [-options]

-display displayname
    Specifies the X server to connect to. If not specified, uses the DISPLAY environment variable.

-help
    Displays help information about the command.

The xsm command displays shared memory usage for an X server. It provides information about the memory segments used by the X server and the clients connected to it.

It is a useful tool for diagnosing memory leaks or excessive memory consumption by X applications. By examining the output, you can identify the largest memory segments and determine which clients are using the most memory.

The command typically needs root or X server user permissions to function correctly. The output can be piped to other utilities for analysis or reporting.

xsm requires appropriate permissions to access the X server's shared memory segments. It may not work correctly if the user does not have sufficient privileges. Output can vary slightly based on the X server version and configuration.

The output of xsm typically shows the shared memory segment ID, the size of the segment, the number of processes attached to the segment, and a list of process IDs (PIDs) that are using the segment. This information can be used to track down the applications consuming the most shared memory.

xsm was originally part of the standard X11 distribution, intended to provide diagnostics for memory utilization. Its usage has diminished with modern system monitoring tools, but it remains useful for specific X server debugging.

xwininfo(1), xprop(1)