>From 99a05473fe9c5aef5619585733265c715ac93f01 Mon Sep 17 00:00:00 2001 From: Gemini Lasswell Date: Tue, 30 Jul 2019 11:56:51 -0700 Subject: [PATCH 2/5] Improve performance of backtrace printing (bug#36566) * lisp/emacs-lisp/cl-print.el (cl-print-to-string-with-limit): Reduce print-level and print-length more quickly when the structure being printed is very large. --- lisp/emacs-lisp/cl-print.el | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-) diff --git a/lisp/emacs-lisp/cl-print.el b/lisp/emacs-lisp/cl-print.el index 5fe3dd1b91..530770128e 100644 --- a/lisp/emacs-lisp/cl-print.el +++ b/lisp/emacs-lisp/cl-print.el @@ -548,21 +548,22 @@ cl-print-to-string-with-limit ;; call_debugger (bug#31919). (let* ((print-length (when limit (min limit 50))) (print-level (when limit (min 8 (truncate (log limit))))) - (delta (when limit - (max 1 (truncate (/ print-length print-level)))))) + (delta-length (when limit + (max 1 (truncate (/ print-length print-level)))))) (with-temp-buffer (catch 'done (while t (erase-buffer) (funcall print-function value (current-buffer)) - ;; Stop when either print-level is too low or the value is - ;; successfully printed in the space allowed. - (when (or (not limit) - (< (- (point-max) (point-min)) limit) - (= print-level 2)) - (throw 'done (buffer-string))) - (cl-decf print-level) - (cl-decf print-length delta)))))) + (let ((result (- (point-max) (point-min)))) + ;; Stop when either print-level is too low or the value is + ;; successfully printed in the space allowed. + (when (or (not limit) (< result limit) (<= print-level 2)) + (throw 'done (buffer-string))) + (let* ((ratio (/ result limit)) + (delta-level (max 1 (min (- print-level 2) ratio)))) + (cl-decf print-level delta-level) + (cl-decf print-length (* delta-length delta-level))))))))) (provide 'cl-print) ;;; cl-print.el ends here -- 2.19.2