eric@yoda.eecs.wsu.edu (Eric Schneider) (04/30/91)
Hi - I'm trying to get our 8mm Exabyte drive to function optimally on a HP/Apollo 400s. The problem is that using rdump(1) seems to give a lot less capacity than the rated values for this drive. Can somebody give me a clue as to why this is? The exabyte writes 1K blocks on the tape and puts an 8K gap when the buffer runs out of data. Is /etc/rmt somehow responsible for writing 512 byte blocks to this device? I'd be very interested in hearing from people who have seen near-capacity storage on this type of drive using rdump. I'd also entertain suggestions for alternative backup programs. Rdump provides a very straightforware means for restoring files (as in restore ivf) and that is why I would like to use it. Thanks in advance for all your help, Eric Schneider -- *------------------------------------------------------------------------------+ | Eric Schneider, Software Engineer | | Advanced Hardware Architectures | | "Any sufficiently rigged demo is indistinguishable from advanced technology".|
smith@wallaby.mrc.uidaho.edu (05/03/91)
In article <1991Apr30.161540.10889@serval.net.wsu.edu> eric@yoda.eecs.wsu.edu (Eric Schneider) writes: >Hi - > > I'm trying to get our 8mm Exabyte drive to function optimally on >a HP/Apollo 400s. The problem is that using rdump(1) seems to give a lot >less capacity than the rated values for this drive. Can somebody give me >a clue as to why this is? The exabyte writes 1K blocks on the tape and >puts an 8K gap when the buffer runs out of data. Is /etc/rmt somehow >responsible for writing 512 byte blocks to this device? I'd be very >interested in hearing from people who have seen near-capacity storage >on this type of drive using rdump. I believe that dump is responsible for the small block sizes. The drive is most efficient (both in speed and space) when block sizes which are multiples of 8K are used. > > I'd also entertain suggestions for alternative backup programs. >Rdump provides a very straightforware means for restoring files (as in >restore ivf) and that is why I would like to use it. Try ftio. That seems to be the most efficient. It allows you to set the block size to just about anything. __ | | ----------------------------- | | William Smith |. | Microelectronics Research Center \ | University of Idaho / \ Moscow, ID 83843 | \ (208)885-6500 | \ | ---| E-mail: wsmith@groucho.mrc.uidaho.edu | | ---------------------------- | | |----------