On Friday 04 November 2005 19:53, Ove Risberg wrote:
> Hi,
>
> On Fri, 2005-11-04 at 14:14, Kern Sibbald wrote:
> > Hello,
> >
> > On Friday 04 November 2005 12:31, Ove Risberg wrote:
> > > Hi,
> > >
> > > I have tried to get some decent performance in my bacula configuration
> > > and after reading bacula mail lists, documentation and some source code
> > > I increased it from 300KB/s to 3MB/s when backuping the root
> > > filesystem.
> > >
> > > After reading the mail lists I found out that I was not the first
> > > bacula user with performance problems and I do not think I will be the
> > > last.
> > >
> > > One thing I was missing while doing this was more tools to test and
> > > tune the performance of tape, database, network and reading files.
> > >
> > > btape has great functions for testing if the tape drive and autochanger
> > > is working but I would like it to test different parameters and suggest
> > > changes to my configuration. I do not mind if would take a long time to
> > > do this because it would take me a lot longer to do it myself.
> > >
> > > Network performance would be much easier to test and tune if I could
> > > tell a file daemon to send data to a storage daemon and report the
> > > transfer rate without reading files, updating database or writing to
> > > tape.
> > >
> > > Reading files can be done in a similar way by telling a file daemon to
> > > read files and report the transfer rate without sending the files to
> > > any storage daemon.
> > >
> > > I do not know how to test and tune the database...
> > > but someone must know ;-)
> > >
> > > When/If these tools are available it would be possible to write a
> > > performance tuning tool to help users to test and tune their bacula
> > > configuration.
> > >
> > > Is it possible to do this?
> >
> > Yes, of course, this is possible. However, there is a question of
> > priorities and manpower. For the moment, manpower is rather limited.
> >
> > You might start by describing what you did, how/why you decided to change
> > what you did, and what the results of each change were. Already, this
> > would be a big help to others.
>
> I will try to describe what I did...
>
> I first found some network problems the bacula server was using 100MBit
> half-duplex and the switch was using 100MBit full-duplex and this is not
> good.
>
> After fixing this the performance was not better... so I tried to scp a
> large file in both directions at the same time to see if there is
> something wrong with the network but I got many MB/s i both directions
> at the same time so the network is not the problem.
>
> Someone told me that LTO drives want large block sizes to perform well
> so I increased MaximumBlockSize to 512K.
> btape complained about the block size so I decresed it to 256K.
> Why is the default value 63K and not 64K?
Because 64K is not supported by all tape drives and will on older drives cause
two records to be written instead of one. It also can cause severe memory
fragmentation. See the Bacula archives for more details on this. The guys
who understand these things *much* better than I do gave a lot of input.
> The performance was not better after fixing this.
>
> Then I found several mails in the bacula-users mail list about
> increasing MaximumNetworkBufferSize in the file and storage daemon
> configuration.
> I first increased it to 65536 and now I got about 3MB/s ;-)
> Then I increased it to 512K, the same value our Netbackup server uses,
> but the performance was not better and I was not able to restore all
> files. The storage daemon died and when trying to read the backup files
> (I made these backup test to files) with bls I could only list the first
> files in the backup and then bls aborted with some error message.
>
> So I changed MaximumNetworkBufferSize to 65535 again.
>
> > Bacula does have some of the capabilities that you described. Some are
> > controlled by directives, and others are controlled by recompiling with
> > #defines changed in src/version.h. However, the defines are a bit out of
> > date and may not work. To make it all work and to put it together in a
> > coherent way that users can try it, is a rather big project.
>
> Do you have any notes, documentation or testscripts using the directives
> or defines in version.h?
>
> I will try to do some testing if I get some hints on how to use these
> features and if I get some useful results I will share it with you all
> on the list.
--
Best regards,
Kern
(">
/\
V_V
-------------------------------------------------------
This SF.Net email is sponsored by the JBoss Inc. Get Certified Today
Register for a JBoss Training Course. Free Certification Exam
for All Training Attendees Through End of 2005. For more info visit:
http://ads.osdn.com/?ad_id=7628&alloc_id=16845&op=click
_______________________________________________
Bacula-users mailing list
Bacula-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bacula-users
