gdb-many-windows causes hangs in emacs 24.5

Question

When running gdb -i=miand then attach to the process for debugging, emacs hangs for like 5 minutes before I can type anything. After trial and error I found it is caused by the following line in my init.el file:

(setq gdb-many-windows t)

Start software to debug->Get Process ID->Start Emacs->Start gdb inside Emacs (with many-window)->Attach to Process->Set break point->Continue->Do things in software GUI to trigger breakpoint->Emacs show break point hit and hangs for 5 minutes

The configuration was never changed, and I only start experiencing this problem recently. So is gdb-many-windows really affecting the performance so bad or if there is some thing else possibly, like the version of emacs or debugger?

GNU Emacs 24.5.1 (x86_64-unknown-linux-gnu, GTK+ Version 2.10.4). GNU gdb (GDB) 7.10.

Answer 1

If thats indeed gdb-many-windows problem. One can avoid using gdb-many-windows and define similar functionality inside the function gdb-get-source-file. You can modify the source file and build from source, but can also defadvice gdb-get-source-file, e.g.

(defadvice gdb-get-source-file (after new-setup-gdb-windows activate)
    (goto-char (point-min))
  (if (re-search-forward gdb-source-file-regexp nil t)
      (setq gdb-main-file (read (match-string 1))))
    (gdb-get-buffer-create 'gdb-stack-buffer)
  (set-window-dedicated-p (selected-window) nil)
  (switch-to-buffer gud-comint-buffer)
  (delete-other-windows)
     (let ((win0 (selected-window))
        (win1 (split-window nil nil 'left))      ;code and output
        (win2 (split-window-below (/ (* (window-height) 2) 3)))     ;stack
        )
    (select-window win2)
    (gdb-set-window-buffer (gdb-stack-buffer-name))
    (select-window win1)
    (set-window-buffer
     win1
     (if gud-last-last-frame
         (gud-find-file (car gud-last-last-frame))
       (if gdb-main-file
           (gud-find-file gdb-main-file)
         ;; Put buffer list in window if we
         ;; can't find a source file.
         (list-buffers-noselect))))
    (setq gdb-source-window (selected-window))
    (let ((win3 (split-window nil (/ (* (window-height) 3) 4)))) ;io
      (gdb-set-window-buffer (gdb-get-buffer-create 'gdb-inferior-io) nil win3))
    (select-window win0)
;;(if gdb-many-windows
;;gdb-setup-windows is previously called here
            )
      (gdb-force-mode-line-update
       (propertize "ready" 'face font-lock-variable-name-face)))

Right now gdb-get-source-file is doing something similar to the original gdb-many-windows file but with fewer buffers.