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- <li><em>date</em>: Mon Aug 2 16:43:20 2004</li>
- <li><em>from</em>: freemyer-ml at NorcrossGroup.com (Greg Freemyer)</li>
- <li><em>in-reply-to</em>: <<a href="msg00057.html">[email protected]</a>></li>
- <li><em>references</em>: <[email protected]> <<a href="msg00056.html">[email protected]</a>> <<a href="msg00057.html">[email protected]</a>></li>
- <li><em>subject</em>: [ale] Tape RAID?</li>
> I'm looking at an array of less expensive drives like the Ecrix gen 2
> drive (still $1k but now does 12MB/sec). this won't come close to
> saturating the U160 controller so hand 2 drives. The Ecrix drives can
> also do variable speed writes by slowing the tape down if the need
> arises.
The slow down feature is important. Thanks for the info. I did not
know anything but LTO had that feture.
> >
> > With that sort of speed, the issue is typically "how do I get data fast
> > enough to keep the drive streaming?", not "how do I make the tape drive
> > faster?".
>
> Dual Gigabit ethernet!
Have you actually measured your backup needs, or are you just assuming
the tape is the bottleneck?
I've done a fair amount of consulting in the backup area, and the issue
is rarely the tape. Normally it is the small size of the files and disk
and/or disk fragmentation issues.
If your backup software will let you backup to /dev/null, try that and
see how fast it runs.
HP recommends that a /dev/null type test be able to run at 2x to 3x the
speed of your tape drive, otherwise the tape buffer will occasionally
empty out and the shoe-shining mode will kick in. Shoe-shining is
_very_ slow.
Greg
--
Greg Freemyer
</pre>
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<li><strong><a name="00059" href="msg00059.html">[ale] Tape RAID?</a></strong>
<ul><li><em>From:</em> jkinney at localnetsolutions.com (James P. Kinney III)</li></ul></li>
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<li><strong><a name="00056" href="msg00056.html">[ale] Tape RAID?</a></strong>
<ul><li><em>From:</em> freemyer-ml at NorcrossGroup.com (Greg Freemyer)</li></ul></li>
<li><strong><a name="00057" href="msg00057.html">[ale] Tape RAID?</a></strong>
<ul><li><em>From:</em> jkinney at localnetsolutions.com (James P. Kinney III)</li></ul></li>
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