From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: "T. V. Raman" Newsgroups: gmane.emacs.devel Subject: Suggestion: vc-hooks.el: Make vc-handled-backends more conservative? Date: Mon, 9 Oct 2006 18:44:55 -0700 Message-ID: <17706.64279.627316.725306@gargle.gargle.HOWL> Reply-To: raman@users.sourceforge.net NNTP-Posting-Host: main.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Trace: sea.gmane.org 1160445590 10932 80.91.229.2 (10 Oct 2006 01:59:50 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Tue, 10 Oct 2006 01:59:50 +0000 (UTC) Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Oct 10 03:59:48 2006 Return-path: Envelope-to: ged-emacs-devel@gmane.org Original-Received: from mail-relay.eunet.no ([193.71.71.242]) by ciao.gmane.org with esmtp (Exim 4.43) id 1GX6gV-00062S-0w for ged-emacs-devel@gmane.org; Tue, 10 Oct 2006 03:46:14 +0200 Original-Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) by mail-relay.eunet.no (8.13.6/8.13.1/GN) with ESMTP id k9A1jB2O071714 for ; Tue, 10 Oct 2006 03:45:11 +0200 (CEST) (envelope-from emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org) Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1GX6g9-0001Yq-UA for ged-emacs-devel@m.gmane.org; Mon, 09 Oct 2006 21:45:09 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1GX6fy-0001Y5-Gy for emacs-devel@gnu.org; Mon, 09 Oct 2006 21:44:58 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1GX6fx-0001XD-0G for emacs-devel@gnu.org; Mon, 09 Oct 2006 21:44:58 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1GX6fw-0001XA-QZ for emacs-devel@gnu.org; Mon, 09 Oct 2006 21:44:56 -0400 Original-Received: from [206.18.177.51] (helo=alnrmhc11.comcast.net) by monty-python.gnu.org with esmtp (Exim 4.52) id 1GX6nc-0008HS-IN for emacs-devel@gnu.org; Mon, 09 Oct 2006 21:52:52 -0400 Original-Received: from localhost (c-71-202-191-236.hsd1.ca.comcast.net[71.202.191.236]) by comcast.net (alnrmhc11) with ESMTP id <20061010014456b110089cd0e>; Tue, 10 Oct 2006 01:44:56 +0000 Original-Received: by localhost (Postfix, from userid 1000) id AAB1212A4002; Mon, 9 Oct 2006 18:44:55 -0700 (PDT) Original-To: emacs-devel@gnu.org X-Mailer: VM 7.19 under Emacs 22.0.50.3 x-attribution: tvr X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org X-Spam-Status: No, score=0.0 required=4.0 tests=BAYES_50,UNPARSEABLE_RELAY autolearn=ham version=3.1.3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on spamd1.kq.no Xref: news.gmane.org gmane.emacs.devel:60568 Archived-At: In vc-hooks.el, vc-handled-backends is presently declared to handle a large number of backends: (defcustom vc-handled-backends '(RCS CVS SVN SCCS Arch MCVS) The last two --arch and MCVS have a particularly bad performance penalty on systems that have NFS mounts in places other than /net or /afs --- se variable vc-ignore-dir-regexp Unless one discovers the above variable (vc-ignore-dir-regexp is declared as a defvar, and not as defcustom) nfs based systems take a heavy performance hit --- since function vc-find-root recursively ascends the directory tree in attempting to check if files are under version control. Suggestions: A) Possibly make vc-handled-backends more conservative by pruning it to have RCS CVS and SVN on it by default. B) Make vc-ignore-dir-regexp a customizable option via defcustom, and add a pointer to it in the docstring for vc-handled-backends so that users discover its purpose In my case I chased it down by examining the source code after observing that emacs was making excessive nfs accesses during file load and save. -- Best Regards, --raman Email: raman@users.sf.net WWW: http://emacspeak.sf.net/raman/ AIM: emacspeak GTalk: tv.raman.tv@gmail.com PGP: http://emacspeak.sf.net/raman/raman-almaden.asc Google: tv+raman IRC: irc://irc.freenode.net/#emacs