Only recurse down into subdirectories if the link count is more than 2.

This results in a 100x speed up on my nnmh spool, and that's from an
SSD disk, and not over nfs.

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 94fb680..1ae82d2 100644 (file)
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,7 @@
+2010-09-04  Lars Magne Ingebrigtsen  <larsi@gnus.org>
+
+       * nnmh.el (nnmh-request-list-1): Optimize for speed.
+
 2010-09-03  Lars Magne Ingebrigtsen  <larsi@gnus.org>
 
        * mm-util.el (mm-image-load-path): Just return the image directories,

diff --git a/lisp/nnmh.el b/lisp/nnmh.el
index 05eb669..86f751c 100644 (file)
--- a/lisp/nnmh.el
+++ b/lisp/nnmh.el
@@ -207,21 +207,29 @@ as unread by Gnus.")
 (defun nnmh-request-list-1 (dir)
   (setq dir (expand-file-name dir))
   ;; Recurse down all directories.
-  (let ((dirs (and (file-readable-p dir)
-                  (nnheader-directory-files dir t nil t)))
-       rdir)
+  (let ((files (nnheader-directory-files dir t nil t))
+       (max 0)
+       min rdir attributes num)
     ;; Recurse down directories.
-    (while (setq rdir (pop dirs))
-      (when (and (file-directory-p rdir)
+    (dolist (rdir files)
+      (setq attributes (file-attributes rdir))
+      (when (null (nth 0 attributes))
+       (setq file (file-name-nondirectory rdir))
+       (when (string-match "^[0-9]+$" file)
+         (setq num (string-to-number file))
+         (setq max (max max num))
+         (when (or (null min)
+                   (< num min))
+           (setq min num))))
+      (when (and (eq (nth 0 attributes) t) ; Is a directory
+                (> (nth 1 attributes) 2)  ; Has sub-directories
                 (file-readable-p rdir)
                 (not (equal (file-truename rdir)
                             (file-truename dir))))
-       (nnmh-request-list-1 rdir))))
-  ;; For each directory, generate an active file line.
-  (unless (string= (expand-file-name nnmh-toplev) dir)
-    (let ((files (mapcar 'string-to-number
-                        (directory-files dir nil "^[0-9]+$" t))))
-      (when files
+       (nnmh-request-list-1 rdir)))
+    ;; For each directory, generate an active file line.
+    (unless (string= (expand-file-name nnmh-toplev) dir)
+      (when min
        (with-current-buffer nntp-server-buffer
          (goto-char (point-max))
          (insert
@@ -233,14 +241,13 @@ as unread by Gnus.")
                (file-truename (file-name-as-directory
                                (expand-file-name nnmh-toplev))))
               dir)
-             (mm-string-to-multibyte   ;Why?  Isn't it multibyte already?
+             (mm-string-to-multibyte ;Why?  Isn't it multibyte already?
               (mm-encode-coding-string
                (nnheader-replace-chars-in-string
                 (substring dir (match-end 0))
                 ?/ ?.)
                nnmail-pathname-coding-system)))
-           (apply 'max files)
-           (apply 'min files)))))))
+           max min))))))
   t)
 
 (deffoo nnmh-request-newgroups (date &optional server)