<html> <head> <base href="https://bugs.freedesktop.org/" /> </head> <body> <div> <a class="bz_bug_link bz_status_RESOLVED bz_closed" title="RESOLVED FIXED - journald can be very slow (on btrfs ?)" href="https://bugs.freedesktop.org/show_bug.cgi?id=78337#c6">Comment # 6</a> on <a class="bz_bug_link bz_status_RESOLVED bz_closed" title="RESOLVED FIXED - journald can be very slow (on btrfs ?)" href="https://bugs.freedesktop.org/show_bug.cgi?id=78337">bug 78337</a> from <a class="email" href="mailto:lennart@poettering.net" title="Lennart Poettering <lennart@poettering.net>"> Lennart Poettering</a> <pre>(In reply to Radek Podgorny from <a href="show_bug.cgi?id=78337#c5">comment #5</a>) > ok, nice! but is it safe? wouldn't the journal be damaged on sudden power > failure, then? (and logs are usually the most important thing to have when > anything goes wrong) With the NOCOW flag set data integrity guarantees on btrfs degrade to the same ones made by ext3/4 which should be pretty much OK. Also, the journal does its own checksumming, and hence should be capable of detecting corruptions (though not fixing them). Given that we have a "mostly append + update ptrs at front" write pattern the expected data loss if some writes are missing or written in the wrong order should be limited: either the pointers are missing but the appended data written, in which case the appended data will simply not be considered but everything else is OK. Or the data is missing and the pointers set up, for which case we have careful checks in place. All in all I think we should be OK.</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the QA Contact for the bug.</li> <li>You are the assignee for the bug.</li> </ul> </body> </html>