Shamless bump. Does anyone have any insight into this? Thanks brian-
On 12/28/2009 2:12 PM, Brian Debelius wrote: > Hi, > I am trying to improve my LTO-3 throughput. I recently installed a > SAS Tandberg LTO-3 drive. I am using Bacula 3.0.3 in Ubuntu. I > backup to disk files, and then copy to tape. The disk files are 4GB > in size. They are stored on a 4 disk RAID 5 array. The raid and the > tape drive are in the same system. > > dd'ing a file from the raid to /dev/null yields: > #dd if=vol-0572 of=/dev/null > 8388576+1 records in > 8388576+1 records out > 4294951097 bytes (4.3 GB) copied, 45.0316 s, 95.4 MB/s > > disabling compression on the tape drive, and > dd'ing the file from raid to /dev/nst1 yields: > #dd if=vol-0572 of=/dev/nst1 bs=64K > 65535+1 records in > 65535+1 records out > 4294951097 bytes (4.3 GB) copied, 77.9708 s, 55.1 MB/s > > enabling compression on the tape drive, and > dd'ing the file from raid to /dev/nst1 yields: > #dd if=vol-0572 of=/dev/nst1 bs=64K > 65535+1 records in > 65535+1 records out > 4294951097 bytes (4.3 GB) copied, 43.1465 s, 99.5 MB/s > > These are the copy job throughput rates. The parent jobs of these > three run concurrently, so all three jobs are in the same disk files. > Rate: 5GB @ 22282.1 KB/s > Rate: 8GB @ 22787.8 KB/s > Rate: 5GB @ 19648.1 KB/s > > With the next two jobs, they do not run concurrent, so each disk file > only contains the data of one job. > Rate: 290GB @ 25024.7 KB/s > Rate: 58GB @ 27998.8 KB/s > > This seems slower then it should be. > > brian- > > ------------------------------------------------------------------------------ This SF.Net email is sponsored by the Verizon Developer Community Take advantage of Verizon's best-in-class app development support A streamlined, 14 day to market process makes app distribution fast and easy Join now and get one step closer to millions of Verizon customers http://p.sf.net/sfu/verizon-dev2dev _______________________________________________ Bacula-users mailing list Bacula-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bacula-users
