Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752086Ab3CJEvd (ORCPT ); Sat, 9 Mar 2013 23:51:33 -0500 Received: from mail-we0-f170.google.com ([74.125.82.170]:52078 "EHLO mail-we0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751124Ab3CJEvb (ORCPT ); Sat, 9 Mar 2013 23:51:31 -0500 MIME-Version: 1.0 In-Reply-To: References: <201211011352.42476.Martin@lichtvoll.de> <6898338.Kmf2pUBmi1@deuteros> <201211101753.46211.Martin@lichtvoll.de> <10569573.iu1a6eiZCO@deuteros> Date: Sat, 9 Mar 2013 23:51:30 -0500 Message-ID: Subject: Fwd: [Nepomuk] Better support for (desktop) file search / indexing applications From: Simeon Bird To: Linux Filesystem Development Mailinglist , linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4160 Lines: 91 Sent again in plain-text - apologies. ---------- Forwarded message ---------- From: Simeon Bird Date: 9 March 2013 23:49 Subject: Re: [Nepomuk] Better support for (desktop) file search / indexing applications To: Tvrtko Ursulin Cc: Martin Steigerwald , Jan Kara , Robert Love , linux-kernel@vger.kernel.org, Eric Paris , Nepomuk Mailing List , Linux Filesystem Development Mailinglist , Eric Paris , John McCutchan On 12 November 2012 04:10, Tvrtko Ursulin wrote: > > On Saturday 10 November 2012 17:53:45 Martin Steigerwald wrote: > > Still fanotify needs root access and thus this would need a daemon running > > as root and some policy kit stuff to access it and in case of mount point > > watches robust and secure code so that each user may only see his/her own > > results. > > Perhaps then also extend fanotify to support user watches, from the top of my > head I can't think of a reason it would be very difficult to implement. But it > has been a few years since I actively worked with that code. > > Since you are not the only group having issues with fanotify feature set I can > see this mini-project (together with extensions from me previous reply) being > useful. It is also better to evolve it than neglect due a few shortcomings and > then in a few years someone will come up with something completely new and > then we will have yet another notification system. > > Tvrtko Hi, We (nepomuk) recently looked at using fanotify, and indeed we would need user watches, support for moves and recursive directory watches (we need to support the case where /home is not a separate filesystem) before it would be useful to us. If you are interested in adding these, we would be delighted to use nepomuk as a test-case for them. We were wondering also if it would be possible to extend inotify a little? Our wishlist is: 1) Recursive folder watches 2) When a file moves, some way to get the destination without watching the directory it moved to, so moves can be tracked without watching every file on the system. I understand that there are reasons of security and performance why you cannot implement 1), but is 2) possible? Maybe by extending IN_MOVED_TO, or adding a new event type? 2) is actually in some ways the more severe problem for us. As well as being an indexer, nepomuk is a system that allows you to store file metadata such as ratings. When users move the files, they want the metadata to move too, so we need to track where the file moved, and thus at the moment we recursively watch everything. This is particularly problematic with removable media; because a lot of people will plug in an external drive and then move files onto it, we have to watch every drive as soon as it is plugged in. If we were able to get the destination of move events without watching the destination directory, we could watch only those directories with interesting metadata in, which would make things a lot easier. inotify move tracking would also be useful for other things - eg, a text editor could use inotify to see if a file it has open has moved and offer to re-open the file in its new location, which is impossible at the moment. Since the lack of recursive watches is really a problem because we have a tendency to run out of watches, it would also really help if the default limit was a bit higher - most people seem to have > 8000 folders, but I suspect far fewer have > 32000 (probably excepting those who are indexing kernel source trees: I have 21000, and half of that is KDE source). Would any of this be possible? If you happen to know of a better way to track moves using existing tools, that would be even better. Thanks, Simeon -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/