Is there a chance that the F/W SCSI channel is the bottleneck? I seem to remember that they are 20mb/sec and that the DLT7000 can go faster than that if it is on a High Speed SCSI channel. Hope I'm not barking down the wrong cable here..... Can anyone confirm or deny? I'm interested in checking out DLT7000's myself, primarily for the high-volume backup capability of 70Gig compressed. Thanks, Howard Hoxsie > -----Original Message----- > From: Carl McNamee [SMTP:[log in to unmask]] > Sent: Monday, April 12, 1999 12:22 PM > To: [log in to unmask] > Subject: Re: DLT7000 vs DLT4000? > > We are using the INTER and MAXTAPEBUF options in Turbo Store. We ditched > Road Runner and that would be another LONG discussion. > > Denys had a good suggestion to see if the data we are working with may be > causing a bottle neck on the disk i/o side. We are going to try a backup > of > the test data to $null and see how long it takes. > > Carl > > > >Because the tape drives are not the limiting factor in your backup speed. > It's > >probably time spent fetching data from disk and preparation for sending > to > >tape. Are you interleaving files on tape? > > >Also, RoadRunner doesn't read a file which spans multiple drives in > logical > >sequence. It is aware of which extents fall on which spindle and reads > extents > >on multiple drives concurrently as much as possible. This also helps > increase > >the parallelism of disc reads during the backup. I don't know whether > >TurboStore also does that, but with the TurboStore default of no > interleaving, > >it's my understanding that the files are always stored in logical order > on > >tape... hence the file has to be read one extent at a time in order. > > >If you use RoadRunner, which if I recall correctly you used to use there, > try > >increasing the interleave to 8. If you use TurboStore, then add the > ;INTER= > >option and run your test again. I would be very interested in seeing the > >results. > >-- > >Jeff Woods > >[log in to unmask] [PGP key available here via finger]