https://lwn.net/Articles/789038/ This is a special feed containing comments posted to the individual LWN article titled "Lazy file reflink". en-us Thu, 13 Nov 2025 01:44:31 +0000 Thu, 13 Nov 2025 01:44:31 +0000 https://www.rssboard.org/rss-specification lwn@lwn.net https://lwn.net/Articles/789318/ https://lwn.net/Articles/789318/ amir73il <div class="FormattedComment"> All the pieces needed for "filesystem change journal" are available in my GitHub repo.<br> Unfortunately, the "filesystem change journal" is not available as a packaged software nor is there proper documentation how to set it up.<br> I would like to make the technology available to users and GNOME Tracker is a classic use case, but haven't had the time to do that.<br> <p> The change tracking is done by a stacked filesystem called "snapshot".<br> This means that if Tracker is indexing /home, then /home should be a "snapshot" mount of (e.g.) /.home<br> and no users should modify /.home directly or changes will be lost.<br> So you see, setting up a "filesystem change journal" is not a programmatic thing, it is an administrative thing, involving boot/login scripts.<br> There is a programmatic interface for GNOME Tracker to actually make use of the change information, but that's the trivial part.<br> <p> If you are a GNOME Tracker developer interested in integrating the technology, I invite you to contact me on linux-fsdevel and I will guide you through the process.<br> <br> The article says "There are some limitations since it is implemented as a stacked filesystem", so let me elaborate on that.<br> When users/applications access /home they now access through a filesystem called "snapshot" and not the original ext4/xfs/btrfs they are used to.<br> This can have many subtle implications, for example, custom ioctls will not work and applications that try to figure out which filesystem<br> they are running on will get confused. This is why I am considering the change to fsnotify model instead of stacked filesystem.<br> </div> Fri, 24 May 2019 06:26:33 +0000 https://lwn.net/Articles/789207/ https://lwn.net/Articles/789207/ tchernobog <div class="FormattedComment"> Thanks for the article, and the link to the GitHub repo.<br> <p> Can someone point me to the code location for the "filesystem change journal" portion? It's what's most interesting to me. I would like to see if GNOME Tracker can be finally be made to behave at a reasonable speed on rotational drives :-p.<br> </div> Thu, 23 May 2019 09:01:58 +0000