pidstat

Monitors system resource usage for individual processes.

Description

pidstat is a command from the sysstat toolset. it is used to monitor the utilization of system resources (CPU, memory, threads, device I/O, etc.) for all or specific processes.

When run for the first time, pidstat displays statistics since system startup. Subsequent runs show statistics since the previous run. Users can specify the number of reports and the time interval between them.

Syntax

pidstat [options] [interval [count]]

Options

• -u: (Default) Display CPU utilization for each process.
• -r: Display memory utilization.
• -d: Display I/O statistics.
• -w: Display context switching activity.
• -t: Display statistics for threads associated with the selected tasks.
• -p <pid>: Monitor only the specified process ID.
• -T { TASK | CHILD | ALL }:
  • TASK: Report independent tasks (default).
  • CHILD: Report cumulative statistics for a process and all its children.
  • ALL: Report both.
• -V: Print version number.
• -h: Display all activities on a single line for easier parsing by other programs.
• -I: In an SMP environment, report CPU usage divided by the total number of processors.
• -l: Display the command name and all its arguments.

Examples

View CPU usage for all processes

# pidstat -u -p ALL
11:04:06 AM   UID       PID    %usr %system  %guest    %CPU   CPU  Command
11:04:06 AM     0         1    0.03    0.05    0.00    0.08    20  systemd
...

Header Meanings:

• PID: Process ID.
• %usr: Percentage of CPU used by the process at the user level.
• %system: Percentage of CPU used by the process at the kernel level.
• %guest: Percentage of CPU used by the process in a virtual machine.
• %CPU: Total percentage of CPU time used by the process.
• CPU: Processor number the process is running on.
• Command: The command associated with the process.

View memory usage for all processes

# pidstat -r
11:10:35 AM   UID       PID  minflt/s  majflt/s     VSZ    RSS   %MEM  Command
11:10:35 AM     0         1      7.24      0.05  191312   4208   0.01  systemd
...

Header Meanings:

• minflt/s: Minor page faults per second (those that don't require loading from disk).
• majflt/s: Major page faults per second (those that require loading from disk).
• VSZ: Virtual size (KB) of the entire task.
• RSS: Resident Set Size (KB) - non-swapped physical memory used.

View I/O usage for all processes

# pidstat -d
11:12:30 AM   UID       PID   kB_rd/s   kB_wr/s kB_ccwr/s  Command
11:12:30 AM     0         1    250.05     11.57      2.13  systemd
...

Header Meanings:

• kB_rd/s: Kilobytes read from disk per second.
• kB_wr/s: Kilobytes written to disk per second.
• kB_ccwr/s: Kilobytes whose writing to disk has been cancelled (e.g., when a task truncates a dirty pagecache).

View context switching activity

# pidstat -w
11:15:52 AM   UID       PID   cswch/s nvcswch/s  Command
11:15:52 AM     0         1      3.15      0.03  systemd
...

Header Meanings:

• cswch/s: Number of voluntary context switches per second.
• nvcswch/s: Number of non-voluntary context switches per second.