Chris Hoogendyk wrote:
Gene Heskett wrote:
On Tuesday 08 December 2009, Charles Curley wrote:
Per Dustin's request, I did a bit of hacking on the readme. My draft is
attached. I culled the release notes and NEWS file. I'd appreciate
comments and corrections back by the end of the business day Monday.
A few questions:
The current example of a fast dump involves filling 2 GB tapes in four
hours.
Boy is that slow. I used ti fill a 4GB in < 2hrs.
Has anyone got a more modern example? As I don't use tapes I
can't provide one. (Several might be nice for the success stories page,
http://wiki.zmanda.com/index.php/Amanda_success_stories.)
I have been using vtapes now for a couple of years, and a 30GB backup
is an hour & 15 mins, sometimes less.
I'm using AIT5, which has a transfer rate of 25MB/s. I'm not really
pushing it to it's limits yet. But, on a recent report, I had 41G with
40 minutes as the reported tape time. Since I'm spreading fulls over 7
dumps per week, the tape usage is pretty low. At the moment, my
overall backup speed is limited by some older servers that are heavily
loaded and are only connected at 100Mb. Those are all on Solaris 9.
Someone with LTO4 would be getting around 4 times that speed or more.
I should ask the sysadmin who's running the clusters -- he's got a
large LTO4 library and a 20TB disk array that he's backing up with
Amanda. I know that he spent some time tuning his system and was well
over 100MB/s in tape speed. He's running Linux, I don't remember for
sure what distribution.
His reply:
Chris,
I'm not on the amanda users list. Feel free to forward on this information.
I'm running Debian Lenny. I have an LTO4 (IBM ULT3580-HH4) connected via
SAS with an LSI PCI-Express controller. The spooling directory on the
backup server has 1.8TB of space and RAID5 across 4 SATA disks.
Currently I'm backing up a 4TB system - but will be also backing up
parts of an 80TB storage system in the near future (just not that often).
I quite often see average tape backup speeds of ~80MB/sec or more. I
have seen over 100MB/sec - which is actually too wide for amreport to
display. I am using amanda 2.5.2 (current version in Debian Lenny).
Craig.
--
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Chris Hoogendyk
-
O__ ---- Systems Administrator
c/ /'_ --- Biology & Geology Departments
(*) \(*) -- 140 Morrill Science Center
~~~~~~~~~~ - University of Massachusetts, Amherst
<[email protected]>
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Erdo"s 4
