API Reference

Exceptions

psutil.NoSuchProcess

Raised when no process with the given PID/parameter was found in the current process list.

psutil.AccessDenied

Exception raised when permission to perform an action is denied.

Classes

psutil.Process(pid)

A class which represents an OS process.

• pid
  The process pid.

• ppid
  The process parent pid.

• parent
  Return the parent process as a Process object. If no ppid is known then return None.

• name
  The process name.

• path
  The process path.

• cmdline
  The command line process has been called with.

• create_time
  The process creation time as a floating point number expressed in seconds since the epoch, in UTC.

• uid
  The real user id of the current process. Where uid doesn't make sense (Windows) always return -1.

• gid
  The real group id of the current process. Where gid doesn't make sense (Windows) always return -1.

• username
  The name of the user that owns the process.

New in 0.1.3

• getcwd()
  Return a string representing the process current working directory.

New in 0.1.3 - Availability Windows, Linux

• get_cpu_times()
  Return a tuple whose values are process CPU user and system times which means the amount of time expressed in seconds that a process has spent in user/system mode.

• get_cpu_percent()
  Compare process times to system time elapsed since last call and calculate CPU utilization as a percentage. It is recommended for accuracy that this function be called with at least 1 second between calls. The initial delta is calculated from the instantiation of the Process object.

• get_memory_info()
  Return a tuple representing RSS (Resident Set Size) and VMS (Virtual Memory Size) in bytes.
  On UNIX RSS and VMS are the same values shown by ps. On Windows RSS and VMS refer to "Mem Usage" and "VM Size" columns of taskmgr.exe.

• get_memory_percent()
  Compare physical system memory to process resident memory and calculate process memory utilization as a percentage.

• is_running()
  Return whether the current process is running in the current process list.

• suspend()
  Suspend process execution.

New in 0.1.3

• resume()
  Resume process execution.

New in 0.1.3

• kill([sig])
  Kill the current process by using signal sig (defaults to SIGKILL).

Functions

psutil.get_pid_list()

Return a list of current running PIDs.

psutil.pid_exists(pid)

Check whether the given PID exists in the current process list.

psutil.process_iter()

Return an iterator yielding a Process class instances for all running processes on the local machine.

System related objects

psutil.cpu_percent()

Return the current system-wide CPU utilization as a percentage. For highest accuracy, it is recommended that this be called at least 1/10th of a second after importing the module or calling cpu_percent() in a previous call, to allow for a larger time delta from which to calculate the percentage value.

psutil.cpu_times()

Return system CPU times as a CPUTimes class object. Every CPU time is accessible in form of a CPUTimes attribute and represents the time CPU has spent in the given mode.
The attributes availability varies depending on the platform. Here follows a list of all available attributes:

- user
- system
- idle
- nice (UNIX)
- iowait (Linux)
- irq (Linux, FreeBSD)
- softirq (Linux)

psutil.TOTAL_PHYMEM
psutil.avail_phymem()
psutil.used_phymem()

Return the amount of total, available and used physical memory on the system, in bytes.

psutil.total_virtmem()
psutil.avail_virtmem()
psutil.used_virtmem()

Return the amount of total, available and used virtual memory on the system, in bytes.
On Linux they match the values returned by free command line utility. On OS X and FreeBSD they represent the same values as returned by sysctl vm.vmtotal. On Windows they are determined by reading the *PageFile values of MEMORYSTATUSEX structure.