I believe (its been a while since I have needed to change my configuration) that my LTO-3 drive does not do hardware compression on blocks over 512K. I am using 256K blocks right now, and I did not see any improvement above that. I am using spooling on a pair of striped hard disks, and despooling happens at 65-80MB/s
On 12/1/2011 10:50 AM, gary artim wrote: > thank much! will try testing with btape. btw, I ran with 20GB maximum > file size/2MB max block (see bacula-sd.conf below) and got these > results, 20MB/s increase, ran 20 minutes faster, got 50MBs -- now if I > can just double the speed I could backup 15TB in about 45/hrs. I don't > have that much data yet, but I'm hovering at 2TB and looking to expand > sharply over time. I'm not doing any networking, it just straight from > a raid 5 to a autochanger/lto-4. gary > > Build OS: x86_64-redhat-linux-gnu redhat > JobId: 6 > Job: Prodbackup.2011-11-30_18.49.24_06 > Backup Level: Full > Client: "bacula-fd" 5.0.3 (04Aug10) > x86_64-redhat-linux-gnu,redhat, > FileSet: "FileSetProd" 2011-11-30 15:23:58 > Pool: "FullProd" (From Job FullPool override) > Catalog: "MyCatalog" (From Client resource) > Storage: "LTO-4" (From Job resource) > Scheduled time: 30-Nov-2011 18:49:15 > Start time: 30-Nov-2011 18:49:26 > End time: 30-Nov-2011 20:14:56 > Elapsed time: 1 hour 25 mins 30 secs > Priority: 10 > FD Files Written: 35,588 > SD Files Written: 35,588 > FD Bytes Written: 257,543,092,723 (257.5 GB) > SD Bytes Written: 257,548,504,514 (257.5 GB) > Rate: 50203.3 KB/s > Software Compression: None > VSS: no > Encryption: no > Accurate: no > Volume name(s): f2 > Volume Session Id: 2 > Volume Session Time: 1322707293 > Last Volume Bytes: 257,600,822,272 (257.6 GB) > Non-fatal FD errors: 0 > SD Errors: 0 > FD termination status: OK > SD termination status: OK > Termination: Backup OK > > bacula-sd.conf: > Device { > Name = LTO-4 > Media Type = LTO-4 > Archive Device = /dev/nst0 > AutomaticMount = yes; # when device opened, read it > AlwaysOpen = yes; > RemovableMedia = yes; > RandomAccess = no; > #Maximum File Size = 12GB > Maximum File Size = 20GB > #Maximum Network Buffer Size = 65536 > Maximum block size = 2M > #Spool Directory = /db/bacula/spool/LTO4 > #Maximum Spool Size = 200G > #Maximum Job Spool Size = 150G > Autochanger = yes > Alert Command = "sh -c 'tapeinfo -f %c |grep TapeAlert|cat'" > Alert Command = "sh -c 'smartctl -H -l error %c'" > } > > > > On Wed, Nov 30, 2011 at 11:48 PM, Andrea Conti<a...@alyf.net> wrote: >> On 30/11/11 19.43, gary artim wrote: >>> Thanks much, I'll try today the block size change first. Then try the >>> spooling. Dont have any unused disk, but may have to try on a shared >>> drive. >>> The "maximum file size" should be okay? g. >> Choosing a max file size is mainly a tradeoff between write performance >> (as the drive will stop and restart at the end of each file to write an >> EOF mark) and restore performance (as the drive can only seek to a file >> mark and then sequentially read through the file until the relevant data >> bocks are found). >> >> I usually set maximum file size so that there are 2-3 filemarks per tape >> wrap (3GB for LTO3, 5GB for LTO4), but if you don't plan to do regular >> restores, or if you always restore the whole contents of a volume, 12GB >> is fine. >> >> Anyway, with the figures you're citing your problem is *not* maximum >> file size. >> >> Try to assess tape performance alone with btape test (which has a >> "speed" command); you can try different block sizes and configuration >> and see which one gives the best results. >> >> Doing so will give you a clear indication on whether your bottleneck is >> in tape or disk throughput. >> >> andrea >> >> ------------------------------------------------------------------------------ >> All the data continuously generated in your IT infrastructure >> contains a definitive record of customers, application performance, >> security threats, fraudulent activity, and more. Splunk takes this >> data and makes sense of it. IT sense. And common sense. >> http://p.sf.net/sfu/splunk-novd2d >> _______________________________________________ >> Bacula-users mailing list >> Bacula-users@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/bacula-users >> > ------------------------------------------------------------------------------ > All the data continuously generated in your IT infrastructure > contains a definitive record of customers, application performance, > security threats, fraudulent activity, and more. Splunk takes this > data and makes sense of it. IT sense. And common sense. > http://p.sf.net/sfu/splunk-novd2d > _______________________________________________ > Bacula-users mailing list > Bacula-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bacula-users ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-novd2d _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users