1 ;;;; This software is part of the SBCL system. See the README file for
4 ;;;; This software is derived from the CMU CL system, which was
5 ;;;; written at Carnegie Mellon University and released into the
6 ;;;; public domain. The software is in the public domain and is
7 ;;;; provided with absolutely no warranty. See the COPYING and CREDITS
8 ;;;; files for more information.
10 (in-package "SB-PROFILE")
12 ;;;; reading internal run time with high resolution and low overhead
14 ;;; FIXME: It might make sense to replace this with something
15 ;;; with finer resolution, e.g. milliseconds or microseconds.
16 ;;; For that matter, maybe we should boost the internal clock
17 ;;; up to something faster, like milliseconds.
19 (defconstant +ticks-per-second+ internal-time-units-per-second)
21 (declaim (inline get-internal-ticks))
22 (defun get-internal-ticks () (get-internal-run-time))
26 ;;; a PCOUNTER is used to represent an unsigned integer quantity which
27 ;;; can grow bigger than a fixnum, but typically does so, if at all,
28 ;;; in many small steps, where we don't want to cons on every step.
29 ;;; (Total system consing, time spent in a profiled function, and
30 ;;; bytes consed in a profiled function are all examples of such
32 (defstruct (pcounter (:copier nil))
33 (integer 0 :type unsigned-byte)
34 (fixnum 0 :type (and fixnum unsigned-byte)))
36 (declaim (ftype (function (pcounter integer) pcounter) incf-pcounter))
37 ;;;(declaim (inline incf-pcounter)) ; FIXME: maybe inline when more stable
38 (defun incf-pcounter (pcounter delta)
39 (let ((sum (+ (pcounter-fixnum pcounter) delta)))
40 (cond ((typep sum 'fixnum)
41 (setf (pcounter-fixnum pcounter) sum))
43 (incf (pcounter-integer pcounter) sum)
44 (setf (pcounter-fixnum pcounter) 0))))
47 (declaim (ftype (function (pcounter) integer) pcounter->integer))
48 ;;;(declaim (inline pcounter->integer)) ; FIXME: maybe inline when more stable
49 (defun pcounter->integer (pcounter)
50 (+ (pcounter-integer pcounter)
51 (pcounter-fixnum pcounter)))
53 ;;;; operations on (OR PCOUNTER FIXNUM)
55 ;;;; When we don't want to cons a PCOUNTER unless we're forced to, we
56 ;;;; start with a FIXNUM counter and only create a PCOUNTER if the
57 ;;;; FIXNUM overflows.
59 (declaim (ftype (function ((or pcounter fixnum) integer) (or pcounter fixnum)) %incf-pcounter-or-fixnum))
60 ;;;(declaim (inline %incf-pcounter-or-fixnum)) ; FIXME: maybe inline when more stable
61 (defun %incf-pcounter-or-fixnum (x delta)
64 (let ((sum (+ x delta)))
65 (if (typep sum 'fixnum)
67 (make-pcounter :integer sum))))
69 (incf-pcounter x delta))))
71 (define-modify-macro incf-pcounter-or-fixnum (delta) %incf-pcounter-or-fixnum)
73 ;;; Trade off space for execution time by handling the common fast
74 ;;; (TYPEP DELTA 'FIXNUM) case inline and only calling generic
75 ;;; arithmetic as a last resort.
76 (defmacro fastbig-incf-pcounter-or-fixnum (x delta)
77 (once-only ((delta delta))
79 (fixnum (incf-pcounter-or-fixnum ,x ,delta))
80 (integer (incf-pcounter-or-fixnum ,x ,delta)))))
82 (declaim (ftype (function ((or pcounter fixnum)) integer) pcounter-or-fixnum->integer))
83 (declaim (maybe-inline pcounter-or-fixnum->integer))
84 (defun pcounter-or-fixnum->integer (x)
87 (pcounter (pcounter->integer x))))
89 ;;;; implementation-dependent interfaces
92 ;;; To avoid unnecessary consing in the "encapsulation" code, we want
93 ;;; find out the number of required arguments, and use &REST to
94 ;;; capture only non-required arguments. This function returns (VALUES
95 ;;; MIN-ARGS OPTIONALS-P), where MIN-ARGS is the number of required
96 ;;; arguments and OPTIONALS-P is true iff there are any non-required
97 ;;; arguments (such as &OPTIONAL, &REST, or &KEY).
98 (declaim (ftype (function ((or symbol cons)) (values fixnum t)) fun-signature))
99 (defun fun-signature (name)
100 (let ((type (info :function :type name)))
101 (cond ((not (function-type-p type))
104 (values (length (function-type-required type))
105 (or (function-type-optional type)
106 (function-type-keyp type)
107 (function-type-rest type)))))))
110 ;;;; global data structures
112 ;;; We associate a PROFILE-INFO structure with each profiled function
113 ;;; name. This holds the functions that we call to manipulate the
114 ;;; closure which implements the encapsulation.
115 (defvar *profiled-function-name->info* (make-hash-table))
116 (defstruct (profile-info (:copier nil))
117 (name (required-argument) :read-only t)
118 (encapsulated-fun (required-argument) :type function :read-only t)
119 (encapsulation-fun (required-argument) :type function :read-only t)
120 (read-stats-fun (required-argument) :type function :read-only t)
121 (clear-stats-fun (required-argument) :type function :read-only t))
123 ;;; These variables are used to subtract out the time and consing for
124 ;;; recursive and other dynamically nested profiled calls. The total
125 ;;; resource consumed for each nested call is added into the
126 ;;; appropriate variable. When the outer function returns, these
127 ;;; amounts are subtracted from the total.
128 (defvar *enclosed-ticks* 0)
129 (defvar *enclosed-consing* 0)
130 (declaim (type (or pcounter fixnum) *enclosed-ticks* *enclosed-consing*))
132 ;;; This variable is also used to subtract out time for nested
133 ;;; profiled calls. The time inside the profile wrapper call --
134 ;;; between its two calls to GET-INTERNAL-TICKS -- is accounted
135 ;;; for by the *ENCLOSED-TIME* variable. However, there's also extra
136 ;;; overhead involved, before we get to the first call to
137 ;;; GET-INTERNAL-TICKS, and after we get to the second call. By
138 ;;; keeping track of the count of enclosed profiled calls, we can try
139 ;;; to compensate for that.
140 (defvar *enclosed-profiles* 0)
141 (declaim (type (or pcounter fixnum) *enclosed-profiles*))
143 ;;; the components of profiling overhead
144 (defstruct (overhead (:copier nil))
145 ;; the number of ticks a bare function call takes. This is
146 ;; factored into the other overheads, but not used for itself.
147 (call (required-argument) :type single-float :read-only t)
148 ;; the number of ticks that will be charged to a profiled
149 ;; function due to the profiling code
150 (internal (required-argument) :type single-float :read-only t)
151 ;; the number of ticks of overhead for profiling that a single
152 ;; profiled call adds to the total runtime for the program
153 (total (required-argument) :type single-float :read-only t))
155 (declaim (type overhead *overhead*))
157 ;;;; profile encapsulations
159 ;;; Trade off space for time by handling the usual all-FIXNUM cases
161 (defmacro fastbig- (x y)
162 (once-only ((x x) (y y))
163 `(if (and (typep ,x 'fixnum)
167 (defmacro fastbig-1+ (x)
169 `(if (typep ,x 'index)
173 ;;; Return a collection of closures over the same lexical context,
174 ;;; (VALUES ENCAPSULATION-FUN READ-STATS-FUN CLEAR-STATS-FUN).
176 ;;; ENCAPSULATION-FUN is a plug-in replacement for ENCAPSULATED-FUN,
177 ;;; which updates statistics whenver it's called.
179 ;;; READ-STATS-FUN returns the statistics:
180 ;;; (VALUES COUNT TIME CONSING PROFILE).
181 ;;; COUNT is the count of calls to ENCAPSULATION-FUN. TICKS is
182 ;;; the total number of ticks spent in ENCAPSULATED-FUN.
183 ;;; CONSING is the total consing of ENCAPSULATION-FUN. PROFILE is the
184 ;;; number of calls to the profiled function, stored for the purposes
185 ;;; of trying to estimate that part of profiling overhead which occurs
186 ;;; outside the interval between the profile wrapper function's timer
189 ;;; CLEAR-STATS-FUN clears the statistics.
191 ;;; (The reason for implementing this as coupled closures, with the
192 ;;; counts built into the lexical environment, is that we hope this
193 ;;; will minimize profiling overhead.)
194 (defun profile-encapsulation-lambdas (encapsulated-fun)
195 (declare (type function encapsulated-fun))
196 (declare (optimize speed safety))
201 (declare (type (or pcounter fixnum) count ticks consing profiles))
204 (lambda (sb-c:&more arg-context arg-count)
205 #+nil (declare (optimize (speed 3) (safety 0))) ; FIXME: remove #+NIL?
206 (fastbig-incf-pcounter-or-fixnum count 1)
209 (inner-enclosed-profiles 0))
210 (declare (type unsigned-byte dticks dconsing))
211 (declare (type unsigned-byte inner-enclosed-profiles))
212 (multiple-value-prog1
213 (let ((start-ticks (get-internal-ticks))
214 ;; KLUDGE: We add (THE UNSIGNED-BYTE ..) wrappers
215 ;; around GET-BYTES-CONSED because as of
216 ;; sbcl-0.6.4, at the time that the FTYPE of
217 ;; GET-BYTES-CONSED is DECLAIMed, the
218 ;; cross-compiler's type system isn't mature enough
219 ;; to do anything about it. -- WHN 20000503
220 (start-consing (the unsigned-byte (get-bytes-consed)))
222 (*enclosed-consing* 0)
223 (*enclosed-profiles* 0))
224 (declare (inline pcounter-or-fixnum->integer))
225 (multiple-value-prog1
226 (multiple-value-call encapsulated-fun
227 (sb-c:%more-arg-values arg-context
230 (setf dticks (fastbig- (get-internal-ticks) start-ticks)
231 dconsing (fastbig- (the unsigned-byte
234 (setf inner-enclosed-profiles
235 (pcounter-or-fixnum->integer *enclosed-profiles*))
236 (fastbig-incf-pcounter-or-fixnum ticks (fastbig-
239 (fastbig-incf-pcounter-or-fixnum consing
243 (fastbig-incf-pcounter-or-fixnum profiles
244 inner-enclosed-profiles)))
245 (fastbig-incf-pcounter-or-fixnum *enclosed-ticks* dticks)
246 (fastbig-incf-pcounter-or-fixnum *enclosed-consing* dconsing)
247 (fastbig-incf-pcounter-or-fixnum *enclosed-profiles*
249 inner-enclosed-profiles)))))
252 (values (pcounter-or-fixnum->integer count)
253 (pcounter-or-fixnum->integer ticks)
254 (pcounter-or-fixnum->integer consing)
255 (pcounter-or-fixnum->integer profiles)))
265 ;;; A symbol or (SETF FOO) list names a function, a string names all
266 ;;; the functions named by symbols in the named package.
267 (defun mapc-on-named-functions (function names)
270 (symbol (funcall function name))
272 ;; We call this just for the side effect of checking that
273 ;; NAME is a legal function name:
274 (function-name-block-name name)
275 ;; Then we map onto it.
276 (funcall function name))
277 (string (let ((package (find-undeleted-package-or-lose name)))
278 (do-symbols (symbol package)
279 (when (eq (symbol-package symbol) package)
280 (when (fboundp symbol)
281 (funcall function symbol))
282 (let ((setf-name `(setf ,symbol)))
283 (when (fboundp setf-name)
284 (funcall function setf-name)))))))))
287 ;;; Profile the named function, which should exist and not be profiled
289 (defun profile-1-unprofiled-function (name)
290 (let ((encapsulated-fun (fdefinition name)))
291 (multiple-value-bind (encapsulation-fun read-stats-fun clear-stats-fun)
292 (profile-encapsulation-lambdas encapsulated-fun)
293 (setf (fdefinition name)
295 (setf (gethash name *profiled-function-name->info*)
296 (make-profile-info :name name
297 :encapsulated-fun encapsulated-fun
298 :encapsulation-fun encapsulation-fun
299 :read-stats-fun read-stats-fun
300 :clear-stats-fun clear-stats-fun))
303 ;;; Profile the named function. If already profiled, unprofile first.
304 (defun profile-1-function (name)
305 (cond ((fboundp name)
306 (when (gethash name *profiled-function-name->info*)
307 (warn "~S is already profiled, so unprofiling it first." name)
308 (unprofile-1-function name))
309 (profile-1-unprofiled-function name))
311 (warn "ignoring undefined function ~S" name)))
314 ;;; Unprofile the named function, if it is profiled.
315 (defun unprofile-1-function (name)
316 (let ((pinfo (gethash name *profiled-function-name->info*)))
318 (remhash name *profiled-function-name->info*)
319 (if (eq (fdefinition name) (profile-info-encapsulation-fun pinfo))
320 (setf (fdefinition name) (profile-info-encapsulated-fun pinfo))
321 (warn "preserving current definition of redefined function ~S"
324 (warn "~S is not a profiled function." name))))
327 (defmacro profile (&rest names)
331 If no names are supplied, return the list of profiled functions.
333 If names are supplied, wrap profiling code around the named functions.
334 As in TRACE, the names are not evaluated. A symbol names a function.
335 A string names all the functions named by symbols in the named
336 package. If a function is already profiled, then unprofile and
337 reprofile (useful to notice function redefinition.) If a name is
338 undefined, then we give a warning and ignore it. See also
339 UNPROFILE, REPORT and RESET."
341 `(loop for k being each hash-key in *profiled-function-name->info*
343 `(mapc-on-named-functions #'profile-1-function ',names)))
345 (defmacro unprofile (&rest names)
347 "Unwrap any profiling code around the named functions, or if no names
348 are given, unprofile all profiled functions. A symbol names
349 a function. A string names all the functions named by symbols in the
350 named package. NAMES defaults to the list of names of all currently
353 `(mapc-on-named-functions #'unprofile-1-function ',names)
356 (defun unprofile-all ()
357 (dohash (name profile-info *profiled-function-name->info*)
358 (declare (ignore profile-info))
359 (unprofile-1-function name)))
362 "Reset the counters for all profiled functions."
363 (dohash (name profile-info *profiled-function-name->info*)
364 (declare (ignore name))
365 (funcall (profile-info-clear-stats-fun profile-info))))
367 ;;;; reporting results
369 (defstruct (time-info (:copier nil))
375 ;;; Return our best guess for the run time in a function, subtracting
376 ;;; out factors for profiling overhead. We subtract out the internal
377 ;;; overhead for each call to this function, since the internal
378 ;;; overhead is the part of the profiling overhead for a function that
379 ;;; is charged to that function.
381 ;;; We also subtract out a factor for each call to a profiled function
382 ;;; within this profiled function. This factor is the total profiling
383 ;;; overhead *minus the internal overhead*. We don't subtract out the
384 ;;; internal overhead, since it was already subtracted when the nested
385 ;;; profiled functions subtracted their running time from the time for
386 ;;; the enclosing function.
387 (defun compensate-time (calls ticks profile)
388 (let ((raw-compensated
389 (- (/ (float ticks) (float +ticks-per-second+))
390 (* (overhead-internal *overhead*) (float calls))
391 (* (- (overhead-total *overhead*)
392 (overhead-internal *overhead*))
394 (max raw-compensated 0.0)))
397 "Report results from profiling. The results are
398 approximately adjusted for profiling overhead, but when RAW is true
399 the unadjusted results are reported. The compensation may be somewhat
400 inaccurate when bignums are involved in runtime calculation, as in
401 a very-long-running Lisp process."
402 (declare (optimize (speed 0)))
403 (unless (boundp '*overhead*)
406 (let ((time-info-list ())
407 (no-call-name-list ()))
408 (dohash (name pinfo *profiled-function-name->info*)
409 (unless (eq (fdefinition name)
410 (profile-info-encapsulation-fun pinfo))
411 (warn "Function ~S has been redefined, so times may be inaccurate.~@
412 PROFILE it again to record calls to the new definition."
414 (multiple-value-bind (calls ticks consing profile)
415 (funcall (profile-info-read-stats-fun pinfo))
417 (push name no-call-name-list)
418 (push (make-time-info :name name
420 :seconds (compensate-time calls
429 :key #'time-info-seconds))
431 (format *trace-output*
432 "~& seconds | consed | calls | sec/call | name~@
433 ------------------------------------------------------~%")
435 (let ((total-time 0.0)
438 (dolist (time-info time-info-list)
439 (incf total-time (time-info-seconds time-info))
440 (incf total-calls (time-info-calls time-info))
441 (incf total-consed (time-info-consing time-info))
442 (format *trace-output*
443 "~10,3F | ~9:D | ~7:D | ~10,6F | ~S~%"
444 (time-info-seconds time-info)
445 (time-info-consing time-info)
446 (time-info-calls time-info)
447 (/ (time-info-seconds time-info)
448 (float (time-info-calls time-info)))
449 (time-info-name time-info)))
450 (format *trace-output*
451 "------------------------------------------------------~@
452 ~10,3F | ~9:D | ~7:D | | Total~%"
453 total-time total-consed total-calls)
454 (format *trace-output*
455 "~%estimated total profiling overhead: ~4,2F seconds~%"
456 (* (overhead-total *overhead*) (float total-calls)))
457 (format *trace-output*
458 "~&overhead estimation parameters:~% ~Ss/call, ~Ss total profiling, ~Ss internal profiling~%"
459 (overhead-call *overhead*)
460 (overhead-total *overhead*)
461 (overhead-internal *overhead*)))
463 (when no-call-name-list
464 (format *trace-output*
465 "~%These functions were not called:~%~{~<~%~:; ~S~>~}~%"
466 (sort no-call-name-list #'string<
468 (symbol-name (function-name-block-name name))))))
472 ;;;; overhead estimation
474 ;;; We average the timing overhead over this many iterations.
475 (defconstant +timer-overhead-iterations+ 50000)
477 ;;; a dummy function that we profile to find profiling overhead
478 (declaim (notinline compute-overhead-aux))
479 (defun compute-overhead-aux (x)
480 (declare (ignore x)))
482 ;;; Return a newly computed OVERHEAD object.
483 (defun compute-overhead ()
485 (let ((start (get-internal-ticks))
486 (fun (symbol-function 'compute-overhead-aux)))
487 (dotimes (i +timer-overhead-iterations+)
489 (/ (float (- (get-internal-ticks) start))
490 (float +ticks-per-second+)
491 (float +timer-overhead-iterations+)))))
492 (let (;; Measure unprofiled calls to estimate call overhead.
493 (call-overhead (frob))
496 ;; Measure profiled calls to estimate profiling overhead.
499 (profile compute-overhead-aux)
501 (- (frob) call-overhead)))
502 (let* ((pinfo (gethash 'compute-overhead-aux
503 *profiled-function-name->info*))
504 (read-stats-fun (profile-info-read-stats-fun pinfo))
505 (time (nth-value 1 (funcall read-stats-fun))))
506 (setf internal-overhead
508 (float +ticks-per-second+)
509 (float +timer-overhead-iterations+))))
510 (unprofile compute-overhead-aux))
511 (make-overhead :call call-overhead
512 :total total-overhead
513 :internal internal-overhead))))
515 ;;; It would be bad to compute *OVERHEAD*, save it into a .core file,
516 ;;; then load old *OVERHEAD* value from the .core file into a
517 ;;; different machine running at a different speed. We avoid this by
518 ;;; erasing *CALL-OVERHEAD* whenever we save a .core file.
520 (makunbound '*overhead*))
521 *before-save-initializations*)