Managing many thousand buffers in emacs

Question

I am on a project with over ten thousand files. I would like to be able to navigate around these files easily.

iswitchb mode bogs down quite badly with this many files; icicles is better in speed, but I like the UI of iswitchb.

Suggestions?

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Stefan requested a profiler run on the iswitchb-mode execution:

- call-interactively                                             2740  79%
  - iswitchb-buffer                                              2628  76%
    - iswitchb                                                   2628  76%
      - iswitchb-read-buffer                                     2628  76%
        - completing-read                                        2599  75%
          - completing-read-default                              2596  75%
            - read-from-minibuffer                               2596  75%
              - iswitchb-post-command                            1034  30%
                - iswitchb-exhibit                               1034  30%
                  - iswitchb-set-common-completion                947  27%
                    - iswitchb-find-common-substri                925  26%
                      - mapcar                                    925  26%
                        - iswitchb-word-matching-s                922  26%
                          + iswitchb-case                          10   0%
                            string-match                            1   0%
                  + iswitchb-set-matches                           63   1%
                  + iswitchb-completions                           24   0%
              + redisplay_internal (C function)                   869  25%
              - timer-event-handler                               499  14%
                - byte-code                                       499  14%
                  - apply                                         499  14%
                    - jit-lock-context-fontify                    491  14%
                      + buffer-list                                15   0%
                    + show-paren-function                           6   0%
                    + display-time-event-handler                    2   0%
              + call-interactively                                 34   0%
              + icicle-unhighlight-lighter                          3   0%
              + iswitchb-pre-command                                1   0%
        + iswitchb-make-buflist                                    15   0%

Answer 1

If you want to use Icicles, but you want the interactive behavior to more closely resemble iswitchb, then there are several customizations you can try, depending on which parts of the iswitchb interaction you like. See this section of the Icicles doc: Icicles - Ido and IswitchB.

Wrt using zillions of files: remember that you can also define projects using Icicles -- sets of related files that you use together. That, like etags and other approaches, is one way to pre-filter the possible file-name candidates.

Answer 2

Have you tried this?

iswitchb-max-to-show is a variable defined in `iswitchb.el'.
Its value is nil

Documentation:
If non-nil, limit the number of names shown in the minibuffer.
If this value is N, and N is greater than the number of matching
buffers, the first N/2 and the last N/2 matching buffers are
shown.  This can greatly speed up iswitchb if you have a
multitude of buffers open.

You can customize this variable.

Answer 3

Having just tried iswitchb in a sessions with 10000 buffers, I see indeed that's it's unbearably slow.

I suggest you try M-x icomplete-mode: in Emacs-24.3, the default C-x b completion already accepts substring matches, just like iswitchb, so the only missing feature is the one offered by icomplete-mode, but icomplete-mode is still perfectly fast in my session with 10000 buffers. Basically, since Emacs-24.3, iswitchb is made obsolete by icomplete-mode.

Answer 4

Can your zillions of files can be organized into useful sets -- even perhaps overlapping sets?

Bookmarks can help a lot with such organization. With Bookmark+, you can bookmark:

• Individual files.
• Sets of files.
• Individual Dired buffers, recording their markings, "omit" settings, and inserted subdirectories.
• Sparse trees of Dired buffers, based on marked subdirectories, recursively.
• Emacs desktops.
• Bookmark files, i.e., sets of bookmarks.
• Bookmark-list displays, with their settings (markings, omissions etc.).

And you can tag bookmarks, delicious-style. Tags are names (arbitrary strings) you pick to categorize bookmarks or files (i.e., autofile bookmarks). You can assign any number of tags to a bookmark. Tags can even have associated (arbitrary) Lisp values.

You can bookmark the same file (or file set) multiple times, and give those different bookmarks different tags.

IOW, there are various ways to define different "views" of files and sets of files.

Answer 5

You can give Helm a try. It can be used for switching buffers and much more: http://amitp.blogspot.hu/2012/10/emacs-helm-for-finding-files.html