'Twas brillig, and Colin Guthrie at 29/11/12 12:22 did gyre and gimble: > 'Twas brillig, and Zbigniew Jędrzejewski-Szmek at 29/11/12 11:48 did > gyre and gimble: >> On Thu, Nov 29, 2012 at 10:37:26AM +0000, Colin Guthrie wrote: >>> Hi, >>> >>> So a couple complaints/queries are beginning trickling in regarding >>> journal space requirements. >>> >>> A user was complaining that rotated journals were taking up too much >>> room and they could be compressed down etc. I did explain that a rotated >>> journal is really any different to the current journal other than it can >>> be sealed, but I do fear he has some kind of point regarding long term >>> storage. >>> >>> Should there be some kind of journal archiver system that will run xz -9 >>> on older journals? Is this something that's being planned or is it left >>> as an exercise for the reader to implement such long term >>> storage/archiving systems? >> >> systemd-journal-remote can be used (when merged) to rewrite journal >> files, so the tools are mostly there. Nevertheless, the data in >> .journal files should already be compressed with XZ (if enabled), so I >> doubt that that would gain much. Do you have some statistics about >> the gains from the additional external XZ compression? > > Hmmm, I wonder if I've missed something obvious in my build then. > > I just took a cleanly rotated journal of 18M in size and it compressed > down to 4M... might be time to look at the build requires :D
OK, so I think I probably was missing an XZ build dep, but even on a local build (where I have the devel libs for it already installed), it still seems to make a big difference... -rw-r----- 1 root adm 4.7M Nov 29 12:36 system.journal -rw-r--r-- 1 root root 132K Nov 29 12:37 system.journal.xz Am I missing something obvious here. Is "XZ...yes" in the configure output enough or do I have to do something special to enable it in the journal too? Or is it just that the uncompressed indexes take up that much space generally or that on-the-fly compression just isn't as efficient as post rotation compression? Col -- Colin Guthrie gmane(at)colin.guthr.ie http://colin.guthr.ie/ Day Job: Tribalogic Limited http://www.tribalogic.net/ Open Source: Mageia Contributor http://www.mageia.org/ PulseAudio Hacker http://www.pulseaudio.org/ Trac Hacker http://trac.edgewall.org/ _______________________________________________ systemd-devel mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/systemd-devel
