1;;; benchmark.el --- support for benchmarking code
2
3;; Copyright (C) 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
4
5;; Author: Dave Love  <fx@gnu.org>
6;; Keywords: lisp, extensions
7
8;; This file is free software; you can redistribute it and/or modify
9;; it under the terms of the GNU General Public License as published by
10;; the Free Software Foundation; either version 2, or (at your option)
11;; any later version.
12
13;; This file is distributed in the hope that it will be useful,
14;; but WITHOUT ANY WARRANTY; without even the implied warranty of
15;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16;; GNU General Public License for more details.
17
18;; You should have received a copy of the GNU General Public License
19;; along with GNU Emacs; see the file COPYING.  If not, write to
20;; the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
21;; Boston, MA 02110-1301, USA.
22
23;;; Commentary:
24
25;; Utilities for timing the execution of forms, including the time
26;; taken for GC.  Note that prior to timing code you may want to
27;; ensure things like:  there has just been a GC, the relevant code is
28;; already loaded (so that there's no overhead from autoloading etc.),
29;; and the code is compiled if appropriate (but see
30;; `benchmark-run-compiled').
31
32;;; Code:
33
34(defmacro benchmark-elapse (&rest forms)
35  "Return the time in seconds elapsed for execution of FORMS."
36  (let ((t1 (make-symbol "t1"))
37	(t2 (make-symbol "t2")))
38    `(let (,t1 ,t2)
39       (setq ,t1 (current-time))
40       ,@forms
41       (setq ,t2 (current-time))
42       (+ (* (- (car ,t2) (car ,t1)) 65536.0)
43	  (- (nth 1 ,t2) (nth 1 ,t1))
44	  (* (- (nth 2 ,t2) (nth 2 ,t1)) 1.0e-6)))))
45(put 'benchmark-elapse 'edebug-form-spec t)
46(put 'benchmark-elapse 'lisp-indent-function 0)
47
48;;;###autoload
49(defmacro benchmark-run (&optional repetitions &rest forms)
50  "Time execution of FORMS.
51If REPETITIONS is supplied as a number, run forms that many times,
52accounting for the overhead of the resulting loop.  Otherwise run
53FORMS once.
54Return a list of the total elapsed time for execution, the number of
55garbage collections that ran, and the time taken by garbage collection.
56See also `benchmark-run-compiled'."
57  (unless (natnump repetitions)
58    (setq forms (cons repetitions forms)
59	  repetitions 1))
60  (let ((i (make-symbol "i"))
61	(gcs (make-symbol "gcs"))
62	(gc (make-symbol "gc")))
63    `(let ((,gc gc-elapsed)
64	   (,gcs gcs-done))
65       (list ,(if (> repetitions 1)
66		  ;; Take account of the loop overhead.
67		  `(- (benchmark-elapse (dotimes (,i ,repetitions)
68					  ,@forms))
69		      (benchmark-elapse (dotimes (,i ,repetitions))))
70		`(benchmark-elapse ,@forms))
71	     (- gcs-done ,gcs)
72	     (- gc-elapsed ,gc)))))
73(put 'benchmark-run 'edebug-form-spec t)
74(put 'benchmark-run 'lisp-indent-function 2)
75
76;;;###autoload
77(defmacro benchmark-run-compiled (&optional repetitions &rest forms)
78  "Time execution of compiled version of FORMS.
79This is like `benchmark-run', but what is timed is a funcall of the
80byte code obtained by wrapping FORMS in a `lambda' and compiling the
81result.  The overhead of the `lambda's is accounted for."
82  (unless (natnump repetitions)
83    (setq forms (cons repetitions forms)
84	  repetitions 1))
85  (let ((i (make-symbol "i"))
86	(gcs (make-symbol "gcs"))
87	(gc (make-symbol "gc"))
88	(code (byte-compile `(lambda () ,@forms)))
89	(lambda-code (byte-compile `(lambda ()))))
90    `(let ((,gc gc-elapsed)
91	   (,gcs gcs-done))
92       (list ,(if (> repetitions 1)
93		  ;; Take account of the loop overhead.
94		  `(- (benchmark-elapse (dotimes (,i ,repetitions)
95					  (funcall ,code)))
96		      (benchmark-elapse (dotimes (,i ,repetitions)
97					  (funcall ,lambda-code))))
98		`(benchmark-elapse (funcall ,code)))
99	     (- gcs-done ,gcs) (- gc-elapsed ,gc)))))
100(put 'benchmark-run-compiled 'edebug-form-spec t)
101(put 'benchmark-run-compiled 'lisp-indent-function 2)
102
103;;;###autoload
104(defun benchmark (repetitions form)
105  "Print the time taken for REPETITIONS executions of FORM.
106Interactively, REPETITIONS is taken from the prefix arg.  For
107non-interactive use see also `benchmark-run' and
108`benchmark-run-compiled'."
109  (interactive "p\nxForm: ")
110  (let ((result (eval `(benchmark-run ,repetitions ,form))))
111    (if (zerop (nth 1 result))
112	(message "Elapsed time: %fs" (car result))
113      (message "Elapsed time: %fs (%fs in %d GCs)" (car result)
114	       (nth 2 result) (nth 1 result)))))
115
116(provide 'benchmark)
117
118;;; arch-tag: be570e24-4b51-4784-adf3-fa2b56c31946
119;;; benchmark.el ends here
120