On Sat, 21.03.15 12:56, Goffredo Baroncelli (kreij...@libero.it) wrote: > From: Goffredo Baroncelli <kreij...@inwind.it> > > Add +C attrib to the journal files directories. The journal file format > behaves bad on a BTRFS filesystem: the performances decrease during the > time. > To avoid this issue, this tmpfile.d snippet sets the NOCOW attribute to the > journal files directories, so newly created journal files inherit the NCOOW > attribute.
I think it would be good if much of this explanation would actually be in the tmpfiles snippet. > > Be aware that the NOCOW attribute disables the BTRFS checksums, prevent BTRFS > to rebuild a corrupted file in a RAIDx filesystem. However the perfomances > increase. > In a single disk filesystem (or a filesystem without redundancy) it is safe > to use the NOCOW flags. > --- > tmpfiles.d/journal-nocow.conf | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > create mode 100644 tmpfiles.d/journal-nocow.conf > > diff --git a/tmpfiles.d/journal-nocow.conf b/tmpfiles.d/journal-nocow.conf > new file mode 100644 > index 0000000..8d9c1e8 > --- /dev/null > +++ b/tmpfiles.d/journal-nocow.conf > @@ -0,0 +1,19 @@ > +# This file is part of systemd. > +# > +# systemd is free software; you can redistribute it and/or modify it > +# under the terms of the GNU Lesser General Public License as published by > +# the Free Software Foundation; either version 2.1 of the License, or > +# (at your option) any later version. > + > +# See tmpfiles.d(5) for details > + > +# set the journal file as NOCOW; make sense only for BTRFS > filesystem This will not set "the journal file" as NOCOW, but will set the flag for the directory as a whole. Please explain this more accurately. > +# WARNING: the NOCOW attribute disables the BTRFS checksums, prevent BTRFS > +# to rebuild a corrupted file in a RAIDx filesystem. It is suggested > +# to disables these setting in this kind of filesystem. > +# However in a single disk filesystem (or a filesystem without > +# redundancy) it is safe to use the NOCOW flag. > +# Setting the NOCOW flag the perfomances increase. This is not correct english. > + > +h /var/log/journal/%m - - - - +C > +h /var/log/journal/remote - - - - +C I think /var/log/journal itself should also get this treatment. Lennart -- Lennart Poettering, Red Hat _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/systemd-devel