Hi, 13.10.2009 10:08, justAck wrote: > Hi, > I still have to learn bacula internals, but urgently need answer for > question regarding fragmentation of restored file(s). > > Perhaps someone did backup of heavily fragmented file (size: ~100G) and then > restored it to clean XFS volume on idle box. > What is more likely: > a) result file will be most likely not fragmented on disk at all
This is most likely in the situation you outline. > b) result file may become fragmented if <some condition> This is always true - you just need to find the right condition :-) > c) result file will be as fragmented as initial file was Very unlikely... Bacula doesn't store information about fragmentation of files, so it can't purposely restore in fragments (which would be very hard on a normal file system anyway). > d) result file may be even more fragmented as initial file was May... sure :-) > The problem is that copying of restored file is ~20% slower than expected > (than other files), I doubt if bacula may be a reason of this slowdown (e.g. > result of restore is very fragmented). I doubt that this is caused by file (system) fragmentation. First thing to find out is if it's Bacula itself that slows things down, the network link between source and target, the target system, or the source system. The most common reasons for slow restores, in my experience, are - Interleaved data on Baculas volumes. This can happen if you run multiple concurrent jobs to the same volume without spooling. Possible cure after the fact: Copy or migrate the jobs in question. - Slow network - Slow target system. As a first step, use vmstat (on linux) and look for high wait time, and use top or ps to find processes using (almost) all the CPU. - Slow source system. Do similar as above, just on the machine running the SD. > Please advice. Does that help? Arno -- Arno Lehmann IT-Service Lehmann Sandstr. 6, 49080 Osnabrück www.its-lehmann.de ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
