From mboxrd@z Thu Jan 1 00:00:00 1970 X-Msuck: nntp://news.gmane.io/gmane.emacs.gnus.general/87860 Path: news.gmane.org!.POSTED!not-for-mail From: Emanuel Berg Newsgroups: gmane.emacs.gnus.general Subject: Re: strange memory usage for nntp groups Date: Thu, 28 Dec 2017 04:04:16 +0100 Message-ID: <86fu7vmu33.fsf@zoho.com> References: <878tdnhocx.fsf@ucl.ac.uk> <86k1x7n49g.fsf@zoho.com> <871sjfraio.fsf@ucl.ac.uk> NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Trace: blaine.gmane.org 1514430195 22192 195.159.176.226 (28 Dec 2017 03:03:15 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Thu, 28 Dec 2017 03:03:15 +0000 (UTC) User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.4 (gnu/linux) To: ding@gnus.org Original-X-From: ding-owner+m36074@lists.math.uh.edu Thu Dec 28 04:03:11 2017 Return-path: Envelope-to: ding-account@gmane.org Original-Received: from mxfilter-048034.atla03.us.yomura.com ([107.189.48.34]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1eUOTO-0005K1-7G for ding-account@gmane.org; Thu, 28 Dec 2017 04:03:10 +0100 X-Yomura-MXScrub: 1.0 Original-Received: from lists1.math.uh.edu (unknown [129.7.128.208]) by mxfilter-048034.atla03.us.yomura.com (Halon) with ESMTPS id eadd7262-eb7b-11e7-83d2-b499baa2b07a; Thu, 28 Dec 2017 03:05:11 +0000 (UTC) Original-Received: from localhost ([127.0.0.1] helo=lists.math.uh.edu) by lists1.math.uh.edu with smtp (Exim 4.89) (envelope-from ) id 1eUOUh-0005aI-HP; Wed, 27 Dec 2017 21:04:31 -0600 Original-Received: from mx2.math.uh.edu ([129.7.128.33]) by lists1.math.uh.edu with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1eUOUe-0005Zn-1F for ding@lists.math.uh.edu; Wed, 27 Dec 2017 21:04:28 -0600 Original-Received: from quimby.gnus.org ([80.91.231.51]) by mx2.math.uh.edu with esmtps (TLSv1.2:DHE-RSA-AES128-SHA:128) (Exim 4.89) (envelope-from ) id 1eUOUc-0006rV-JH for ding@lists.math.uh.edu; Wed, 27 Dec 2017 21:04:27 -0600 Original-Received: from [195.159.176.226] (helo=blaine.gmane.org) by quimby.gnus.org with esmtps (TLS1.2:RSA_AES_128_CBC_SHA1:128) (Exim 4.80) (envelope-from ) id 1eUOUb-0006qB-A7 for ding@gnus.org; Thu, 28 Dec 2017 04:04:25 +0100 Original-Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1eUOSa-00026i-7F for ding@gnus.org; Thu, 28 Dec 2017 04:02:20 +0100 X-Injected-Via-Gmane: http://gmane.org/ Mail-Followup-To: ding@gnus.org Original-Lines: 74 Original-X-Complaints-To: usenet@blaine.gmane.org Mail-Copies-To: never Cancel-Lock: sha1:dxifr+WTmf6niwjv4b1RV+i0jvg= X-Spam-Score: -0.6 (/) List-ID: Precedence: bulk Xref: news.gmane.org gmane.emacs.gnus.general:87860 Archived-At: Eric S Fraga wrote: > Ah, interesting; it could be. > My gmane.linux.debian.user overview file, for > instance, is 162Mb! > > Is there a solution? What if I delete the > overview file? Will having it regenerate lead > to the same size? >From what I can understand from the manual entry, yanked last in this posts, the overview files are generated by Gnus only for nnml; for NNTP, the server makes them, so I suppose additions are communicated and appended locally. If so, deleting a file will help but eventually it will grow back to size. Also, what functionality will be *lost* this way? The ability to access old posts? In general, the purpose of the overview files isn't clear to me from the manual entry. It seems to be some scheme with the purpose, interestingly, to speed up populating the summary buffer! "NOV" NOV stands for News OverView, which is a type of news server header which provide datas containing the condensed header information of articles. They are produced by the server itself; in the ‘nntp’ back end Gnus uses the ones that the NNTP server makes, but Gnus makes them by itself for some backends (in particular, ‘nnml’). When Gnus enters a group, it asks the back end for the headers of all unread articles in the group. Most servers support the News OverView format, which is more compact and much faster to read and parse than the normal HEAD format. The NOV data consist of one or more text lines (*note Motion by Text Lines: (elisp)Text Lines.) where each line has the header information of one article. The header information is a tab-separated series of the header’s contents including an article number, a subject, an author, a date, a message-id, references, etc. Those data enable Gnus to generate summary lines quickly. However, if the server does not support NOV or you disable it purposely or for some reason, Gnus will try to generate the header information by parsing each article’s headers one by one. It will take time. Therefore, it is not usually a good idea to set nn*-nov-is-evil (*note Slow/Expensive Connection::) to a non-‘nil’ value unless you know that the server makes wrong NOV data. [1] [1] line 23594, /usr/share/info/emacs-24/gnus.info.gz -- underground experts united http://user.it.uu.se/~embe8573