Re: no improvement using buffer with tar?
On Wed, 3 Feb 1999 servis@purdue.edu wrote:
> I guess I was a little disappointed with respect to its claims and its
> actual performance. I would like to speed up my backup, as it is now a
> backup of my system containing about 5.5Gigs takes almost 5.5hrs. That
> is only about 275k/s transfer rate which is way below the capabilities
> of the drive. Which leads me to believe there can be improvements on the
> software side of my backup.
Listen to the tape while it is running, it should basically emit a nice
constant sound. If it doesn't and you hear it 'back up' then that is why
things are so slow for you. It may well be that you bought a tape drive
that requires a higher data rate than your PCee can sustain, this is what
buffer is supposed to help with. Make a -really- big buffer (like 10-50
meg) and set the low/high marks at the far end so that it generates a big
wack meg of data and then starts feeding the tape.. Now if your disks and
your CPU (compression) can mostly keep up with the tape then you will be
fine with this, but if the tape vastly outmatches your systems performance
(ie it can stream 2meg/sec or something crazy like that) then you will
see little or no speed gain and possibly even a loss.
Jason
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