On Thu, Aug 02, 2007 at 12:03:35PM -0400, Jean-Francois Malouin wrote: > > My bad, replying to myself... > Here's the outpout of 2 simultaneous running dd's on non-compressing > tape devices daisy-chained to the same scsi hba (LSI U320 PCI-X): > > grumpy:~# time dd if=/dev/zero of=/dev/nst0 bs=32k > dd: writing `/dev/nst0': No space left on device > 12424636+0 records in > 12424635+0 records out > 407130439680 bytes (407 GB) copied, 7003.39 seconds, 58.1 MB/s > > real 116m43.419s > user 0m11.317s > sys 3m7.260s > > grumpy:~# time dd if=/dev/zero of=/dev/nst1 bs=32k > dd: writing `/dev/nst1': No space left on device > 12424636+0 records in > 12424635+0 records out > 407130439680 bytes (407 GB) copied, 7002.45 seconds, 58.1 MB/s > > real 116m42.477s > user 0m11.677s > sys 3m6.480s > > Looks good to me. > Not sure why amtapetype tops at 40MBs. >
Size is less than amtapetype: Earlier you said amtapetype gave ~386GB. dd's decimal 407 gig is 379GB binary. As to speed, dd is only using the scsi controller for writing, does amtapetype use it to also read its data? jl -- Jon H. LaBadie [EMAIL PROTECTED] JG Computing 4455 Province Line Road (609) 252-0159 Princeton, NJ 08540-4322 (609) 683-7220 (fax)