On 09/25/2012 10:43 AM, Alan Brown wrote: > On 25/09/12 17:43, Stephen Thompson wrote: >> Our Sun/Oracle service engineer claims that our drives do not require >> cleaning tapes. Does that sound legit? > > In general: true (as in, "Don't do it as a scheduled item"), but all LTO > drives require cleaning tapes from time to time and sometimes benefit > from loading one even if the "clean" light isn't on. It primarily > depends on the cleanliness of the room where the drive is. > >> Our throughput is pretty reasonable for our hardware -- we do use disk >> staging and get something like 60Mb/s to tape. > > 60Mb/s is _slow_ for LTO3. You need to take a serious look at what > you're using as stage disk and consider using a raid0 array of SSDs in > order to keep up. > >> Lastly, the tapes that get 200 vs 800 are from the same batch of tapes, > same number of uses, and used by the same pair of SL500 drives. That's > primarily why I wondered if it could be data dependent (or a bacula bug). > > > What happens if you mark the volumes as "append" and put them back in > the library?
I haven't had a lot of time to look into this today, but I do this quick test and it immediately marks the volume Full again. 27-Sep 14:20 sd-SL500 JobId 260069: Volume "FB0763" previously written, moving to end of data. 27-Sep 14:21 sd-SL500 JobId 260069: Ready to append to end of Volume "FB0763" at file=110. 27-Sep 14:21 sd-SL500 JobId 260069: Spooling data ... 27-Sep 14:21 sd-SL500 JobId 260069: Job write elapsed time = 00:00:01, Transfer rate = 759.3 K Bytes/second 27-Sep 14:21 sd-SL500 JobId 260069: Committing spooled data to Volume "FB0763". Despooling 762,358 bytes ... 27-Sep 14:21 sd-SL500 JobId 260069: End of Volume "FB0763" at 110:1 on device "SL500-Drive-0" (/dev/SL500-Drive-0). Write of 262144 bytes got -1. 27-Sep 14:21 sd-SL500 JobId 260069: Re-read of last block succeeded. 27-Sep 14:21 sd-SL500 JobId 260069: End of medium on Volume "FB0763" Bytes=219,730,936,832 Blocks=838,207 at 27-Sep-2012 14:21. 27-Sep 14:21 sd-SL500 JobId 260069: 3307 Issuing autochanger "unload slot 36, drive 0" command. > > I've seen transient scsi errors result in tapes being marked as full. > > What does smartctl show for the drive and tape in question? (run this > against the /dev/sg of the tape drive) > > > -- Stephen Thompson Berkeley Seismological Laboratory step...@seismo.berkeley.edu 215 McCone Hall # 4760 404.538.7077 (phone) University of California, Berkeley 510.643.5811 (fax) Berkeley, CA 94720-4760 ------------------------------------------------------------------------------ Everyone hates slow websites. So do we. Make your web apps faster with AppDynamics Download AppDynamics Lite for free today: http://ad.doubleclick.net/clk;258768047;13503038;j? http://info.appdynamics.com/FreeJavaPerformanceDownload.html _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
