From: Lars Ingebrigtsen Date: Fri, 11 Dec 2020 13:49:53 +0000 (+0100) Subject: Add a new command `memory-report' X-Git-Tag: emacs-28.0.90~4789 X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=004d7e97e2c54c1089a776055ffd173d132fe5ae;p=emacs.git Add a new command `memory-report' * doc/lispref/internals.texi (Garbage Collection): Document it. * lisp/emacs-lisp/memory-report.el: New package. --- diff --git a/doc/lispref/internals.texi b/doc/lispref/internals.texi index bb25983aa4b..fb24544c917 100644 --- a/doc/lispref/internals.texi +++ b/doc/lispref/internals.texi @@ -615,6 +615,19 @@ during garbage collection so far in this Emacs session, as a floating-point number. @end defvar +@defun memory-report +It can sometimes be useful to see where Emacs is using memory (in +various variables, buffers, and caches). This command will open a new +buffer (called @samp{"*Memory Report*"}) that will give an overview, +in addition to listing the ``largest'' buffers and variables. + +All the data here is approximate, because there's really no consistent +way to compute the size of a variable. For instance, two variables +may share parts of a data structure, and this will be counted twice, +but this command may still give a useful high-level overview of which +parts of Emacs is using memory. +@end defun + @node Stack-allocated Objects @section Stack-allocated Objects diff --git a/etc/NEWS b/etc/NEWS index 1640e277987..33cc2c30a08 100644 --- a/etc/NEWS +++ b/etc/NEWS @@ -275,6 +275,11 @@ preserving markers, properties and overlays. The new variable number of seconds that 'revert-buffer-with-fine-grain' should spend trying to be non-destructive. ++++ +** New command 'memory-report'. +This command opens a new buffer called "*Memory Report*" and gives a +summary of where Emacs is using memory currently. + ** Outline +++ diff --git a/lisp/emacs-lisp/memory-report.el b/lisp/emacs-lisp/memory-report.el new file mode 100644 index 00000000000..58555fa9f0d --- /dev/null +++ b/lisp/emacs-lisp/memory-report.el @@ -0,0 +1,299 @@ +;;; memory-report.el --- Short function summaries -*- lexical-binding: t -*- + +;; Copyright (C) 2020 Free Software Foundation, Inc. + +;; Keywords: lisp, help + +;; This file is part of GNU Emacs. + +;; GNU Emacs is free software: you can redistribute it and/or modify +;; it under the terms of the GNU General Public License as published by +;; the Free Software Foundation, either version 3 of the License, or +;; (at your option) any later version. + +;; GNU Emacs is distributed in the hope that it will be useful, +;; but WITHOUT ANY WARRANTY; without even the implied warranty of +;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +;; GNU General Public License for more details. + +;; You should have received a copy of the GNU General Public License +;; along with GNU Emacs. If not, see . + +;;; Commentary: + +;; Todo (possibly): Font cache, regexp cache, bidi cache, various +;; buffer caches (newline cache, free_region_cache, etc), composition +;; cache, face cache. + +;;; Code: + +(require 'seq) +(require 'subr-x) +(eval-when-compile (require 'cl-lib)) + +(defvar memory-report--type-size (make-hash-table)) + +;;;###autoload +(defun memory-report () + "Generate a report of how Emacs is using memory. + +This report is approximate, and will commonly over-count memory +usage by variables, because shared data structures will usually +by counted more than once." + (interactive) + (pop-to-buffer "*Memory Report*") + (special-mode) + (button-mode 1) + (setq truncate-lines t) + (message "Gathering data...") + (let ((reports (append (memory-report--garbage-collect) + (memory-report--image-cache) + (memory-report--buffers) + (memory-report--largest-variables))) + (inhibit-read-only t) + summaries details) + (message "Gathering data...done") + (erase-buffer) + (insert (propertize "Estimated Emacs Memory Usage\n\n" 'face 'bold)) + (dolist (report reports) + (if (listp report) + (push report summaries) + (push report details))) + (dolist (summary (nreverse summaries)) + (insert (format "%s %s\n" + (memory-report--format (cdr summary)) + (car summary)))) + (insert "\n") + (dolist (detail (nreverse details)) + (insert detail "\n"))) + (goto-char (point-min))) + +(defun memory-report-object-size (object) + "Return the size of OBJECT in bytes." + (unless memory-report--type-size + (memory-report--garbage-collect)) + (memory-report--object-size (make-hash-table :test #'eq) object)) + +(defun memory-report--size (type) + (or (gethash type memory-report--type-size) + (gethash 'object memory-report--type-size))) + +(defun memory-report--set-size (elems) + (setf (gethash 'string memory-report--type-size) + (cadr (assq 'strings elems))) + (setf (gethash 'cons memory-report--type-size) + (cadr (assq 'conses elems))) + (setf (gethash 'symbol memory-report--type-size) + (cadr (assq 'symbols elems))) + (setf (gethash 'object memory-report--type-size) + (cadr (assq 'vectors elems))) + (setf (gethash 'float memory-report--type-size) + (cadr (assq 'floats elems))) + (setf (gethash 'buffer memory-report--type-size) + (cadr (assq 'buffers elems)))) + +(defun memory-report--garbage-collect () + (let ((elems (garbage-collect))) + (memory-report--set-size elems) + (let ((data (list + (list 'strings + (+ (memory-report--gc-elem elems 'strings) + (memory-report--gc-elem elems 'string-bytes))) + (list 'vectors + (+ (memory-report--gc-elem elems 'vectors) + (memory-report--gc-elem elems 'vector-slots))) + (list 'floats (memory-report--gc-elem elems 'floats)) + (list 'conses (memory-report--gc-elem elems 'conses)) + (list 'symbols (memory-report--gc-elem elems 'symbols)) + (list 'intervals (memory-report--gc-elem elems 'intervals)) + (list 'buffer-objects + (memory-report--gc-elem elems 'buffers))))) + (list (cons "Overall Object Memory Usage" + (seq-reduce #'+ (mapcar (lambda (elem) + (* (nth 1 elem) (nth 2 elem))) + elems) + 0)) + (cons "Reserved (But Unused) Object Memory" + (seq-reduce #'+ (mapcar (lambda (elem) + (if (nth 3 elem) + (* (nth 1 elem) (nth 3 elem)) + 0)) + elems) + 0)) + (with-temp-buffer + (insert (propertize "Object Storage\n\n" 'face 'bold)) + (dolist (object (seq-sort (lambda (e1 e2) + (> (cadr e1) (cadr e2))) + data)) + (insert (format "%s %s\n" + (memory-report--format (cadr object)) + (capitalize (symbol-name (car object)))))) + (buffer-string)))))) + +(defun memory-report--largest-variables () + (let ((variables nil)) + (mapatoms + (lambda (symbol) + (when (boundp symbol) + (let ((size (memory-report--object-size + (make-hash-table :test #'eq) + (symbol-value symbol)))) + (when (> size 1000) + (push (cons symbol size) variables))))) + obarray) + (list + (cons (propertize "Memory Used By Global Variables" + 'help-echo "Upper bound; mutually overlapping data from different variables are counted several times") + (seq-reduce #'+ (mapcar #'cdr variables) 0)) + (with-temp-buffer + (insert (propertize "Largest Variables\n\n" 'face 'bold)) + (cl-loop for i from 1 upto 20 + for (symbol . size) in (seq-sort (lambda (e1 e2) + (> (cdr e1) (cdr e2))) + variables) + do (insert (memory-report--format size) + " " + (symbol-name symbol) + "\n")) + (buffer-string))))) + +(defun memory-report--object-size (counted value) + (if (gethash value counted) + 0 + (setf (gethash value counted) t) + (memory-report--object-size-1 counted value))) + +(cl-defgeneric memory-report--object-size-1 (_counted _value) + 0) + +(cl-defmethod memory-report--object-size-1 (_ (value symbol)) + ;; Don't count global symbols -- makes sizes of lists of symbols too + ;; heavey. + (if (intern-soft value obarray) + 0 + (memory-report--size 'symbol))) + +(cl-defmethod memory-report--object-size-1 (_ (_value buffer)) + (memory-report--size 'buffer)) + +(cl-defmethod memory-report--object-size-1 (counted (value string)) + (+ (memory-report--size 'string) + (string-bytes value) + (memory-report--interval-size counted (object-intervals value)))) + +(defun memory-report--interval-size (counted intervals) + ;; We get a list back of intervals, but only count the "inner list" + ;; (i.e., the actual text properties), and add the size of the + ;; intervals themselves. + (+ (* (memory-report--size 'interval) (length intervals)) + (seq-reduce #'+ (mapcar + (lambda (interval) + (memory-report--object-size counted (nth 2 interval))) + intervals) + 0))) + +(cl-defmethod memory-report--object-size-1 (counted (value list)) + (let ((total 0) + (size (memory-report--size 'cons))) + (while value + (cl-incf total size) + (setf (gethash value counted) t) + (when (car value) + (cl-incf total (memory-report--object-size counted (car value)))) + (if (cdr value) + (if (consp (cdr value)) + (setq value (cdr value)) + (cl-incf total (memory-report--object-size counted (cdr value))) + (setq value nil)) + (setq value nil))) + total)) + +(cl-defmethod memory-report--object-size-1 (counted (value vector)) + (let ((total (+ (memory-report--size 'vector) + (* (memory-report--size 'object) (length value))))) + (cl-loop for elem across value + do (setf (gethash elem counted) t) + (cl-incf total (memory-report--object-size counted elem))) + total)) + +(cl-defmethod memory-report--object-size-1 (counted (value hash-table)) + (let ((total (+ (memory-report--size 'vector) + (* (memory-report--size 'object) (hash-table-size value))))) + (maphash + (lambda (key elem) + (setf (gethash key counted) t) + (setf (gethash elem counted) t) + (cl-incf total (memory-report--object-size counted key)) + (cl-incf total (memory-report--object-size counted elem))) + value) + total)) + +(defun memory-report--format (bytes) + (setq bytes (/ bytes 1024.0)) + (let ((units '("kB" "MB" "GB" "TB"))) + (while (>= bytes 1024) + (setq bytes (/ bytes 1024.0)) + (setq units (cdr units))) + (format "%5.1f%s" bytes (car units)))) + +(defun memory-report--gc-elem (elems type) + (* (nth 1 (assq type elems)) + (nth 2 (assq type elems)))) + +(defun memory-report--buffers () + (let ((buffers (mapcar (lambda (buffer) + (cons buffer (memory-report--buffer buffer))) + (buffer-list)))) + (list (cons "Total Buffer Memory Usage" + (seq-reduce #'+ (mapcar #'cdr buffers) 0)) + (with-temp-buffer + (insert (propertize "Largest Buffers\n\n" 'face 'bold)) + (cl-loop for i from 1 upto 20 + for (buffer . size) in (seq-sort (lambda (e1 e2) + (> (cdr e1) (cdr e2))) + buffers) + do (insert (memory-report--format size) + " " + (button-buttonize + (buffer-name buffer) + #'memory-report--buffer-details buffer) + "\n")) + (buffer-string))))) + +(defun memory-report--buffer-details (buffer) + (with-current-buffer buffer + (apply + #'message + "Buffer text: %s; variables: %s; text properties: %s; overlays: %s" + (mapcar #'string-trim (mapcar #'memory-report--format + (memory-report--buffer-data buffer)))))) + +(defun memory-report--buffer (buffer) + (seq-reduce #'+ (memory-report--buffer-data buffer) 0)) + +(defun memory-report--buffer-data (buffer) + (with-current-buffer buffer + (list (save-restriction + (widen) + (+ (position-bytes (point-max)) + (- (position-bytes (point-min))) + (gap-size))) + (seq-reduce #'+ (mapcar (lambda (elem) + (if (cdr elem) + (memory-report--object-size + (make-hash-table :test #'eq) + (cdr elem)) + 0)) + (buffer-local-variables buffer)) + 0) + (memory-report--object-size (make-hash-table :test #'eq) + (object-intervals buffer)) + (memory-report--object-size (make-hash-table :test #'eq) + (overlay-lists))))) + +(defun memory-report--image-cache () + (list (cons "Total Image Cache Size" (image-cache-size)))) + +(provide 'memory-report) + +;;; memory-report.el ends here diff --git a/test/lisp/emacs-lisp/memory-report-tests.el b/test/lisp/emacs-lisp/memory-report-tests.el new file mode 100644 index 00000000000..01bcf18423a --- /dev/null +++ b/test/lisp/emacs-lisp/memory-report-tests.el @@ -0,0 +1,54 @@ +;;; memory-report-tests.el --- tests for memory-report.el -*- lexical-binding: t -*- + +;; Copyright (C) 2016-2020 Free Software Foundation, Inc. + +;; This file is part of GNU Emacs. + +;; GNU Emacs is free software: you can redistribute it and/or modify +;; it under the terms of the GNU General Public License as published by +;; the Free Software Foundation, either version 3 of the License, or +;; (at your option) any later version. + +;; GNU Emacs is distributed in the hope that it will be useful, +;; but WITHOUT ANY WARRANTY; without even the implied warranty of +;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +;; GNU General Public License for more details. + +;; You should have received a copy of the GNU General Public License +;; along with GNU Emacs. If not, see . + +(require 'ert) +(require 'memory-report) + +(defun setup-memory-report-tests () + (memory-report--set-size + '((conses 16 499173 99889) + (symbols 48 22244 3) + (strings 32 92719 4559) + (string-bytes 1 40402011) + (vectors 16 31919) + (vector-slots 8 385148 149240) + (floats 8 434 4519) + (intervals 56 24499 997) + (buffers 984 33)))) + +(ert-deftest memory-report-sizes () + (setup-memory-report-tests) + (should (equal (memory-report-object-size (cons nil nil)) 16)) + (should (equal (memory-report-object-size (cons 1 2)) 16)) + + (should (equal (memory-report-object-size (list 1 2)) 32)) + (should (equal (memory-report-object-size (list 1)) 16)) + + (should (equal (memory-report-object-size (list 'foo)) 16)) + + (should (equal (memory-report-object-size (vector 1 2 3 4)) 80)) + + (should (equal (memory-report-object-size "") 32)) + (should (equal (memory-report-object-size "a") 33)) + (should (equal (memory-report-object-size (propertize "a" 'face 'foo)) + 81))) + +(provide 'memory-report-tests) + +;;; memory-report-tests.el ends here