Info Catalog elisp: Time Parsing elisp: System Interface elisp: Time Calculations

elisp: Processor Run Time

 
 38.9 Processor Run time
 =======================
 
 Emacs provides several functions and primitives that return time, both
 elapsed and processor time, used by the Emacs process.
 
  -- Command: emacs-uptime &optional format
      This function returns a string representing the Emacs “uptime”—the
      elapsed wall-clock time this instance of Emacs is running.  The
      string is formatted by ‘format-seconds’ according to the optional
      argument FORMAT.  For the available format descriptors, see 
      format-seconds Time Parsing.  If FORMAT is ‘nil’ or omitted, it
      defaults to ‘"%Y, %D, %H, %M, %z%S"’.
 
      When called interactively, it prints the uptime in the echo area.
 
  -- Function: get-internal-run-time
      This function returns the processor run time used by Emacs as a
      list of four integers: ‘(SEC-HIGH SEC-LOW MICROSEC PICOSEC)’, using
      the same format as ‘current-time’ (Time of Day).
 
      Note that the time returned by this function excludes the time
      Emacs was not using the processor, and if the Emacs process has
      several threads, the returned value is the sum of the processor
      times used up by all Emacs threads.
 
      If the system doesn’t provide a way to determine the processor run
      time, ‘get-internal-run-time’ returns the same time as
      ‘current-time’.
 
  -- Command: emacs-init-time
      This function returns the duration of the Emacs initialization
      (Startup Summary) in seconds, as a string.  When called
      interactively, it prints the duration in the echo area.
 

Info Catalog elisp: Time Parsing elisp: System Interface elisp: Time Calculations