Re: AVg Tape Write Rate

On Wed, 10 Jul 2002, Douglas Bollinger wrote:

> On Wed, 10 Jul 2002 11:10:18 +0930
> Pete <[email protected]> wrote:
> 
> > I always expected tape backup to be slow, so I never thought about
> > that... anyone getting faster results?
> 
> I have a TR3 tape drive hooked-up to the floppy port.  While it's certainly
> not speedy, I don't think it's this slow.
> 
> Can someone provide an easy way to benchmark tape drive performance using
> common unix tools?

If you use GNU tar to do a big enough backup to get a good average (100 Megs or so), it will spit out average throughput in Kb/sec if you give it the
"--totals" option.  The output looks like this:

Total bytes written: 8069570560 (7.5GB, 897kB/s)

My floppy drive yields 78 Kb/sec.  For comparison, a TR-5 IDE drive gets
897 Kb/sec.  The driver by default limits the rate for floppy drives.  If you
think your floppy interface can do better, then there is a driver parameter to
speed it up (ft_fdc_rate_limit).  But it can crash the system if the floppy
interface can't hack it, so sync up first.

My Eagle drive can do 160 Kb/sec, I believe.  Although my motherboard is
May 1996, the floppy chip locks up at the faster rate.  I haven't looked
at the actual floppy chip (if it is even a separate package).

-- 
			Stuart D. Gathman <[email protected]>
      Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
	"[Microsoft] products are even less buggy than others, in terms of
	    per capita usage." - Steve Balmer, Microsoft Corporation

-
To unsubscribe from this list: send the line "unsubscribe linux-tape" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html