Networker

Re: [Networker] Cloning parallelism

2008-01-28 02:48:05
Subject: Re: [Networker] Cloning parallelism
From: Tim Verbois <Tim.Verbois AT ET.VLAANDEREN DOT BE>
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Date: Mon, 28 Jan 2008 08:44:04 +0100
VTL from SUN

Peter Viertel wrote:
What VTL is this?   Given that networker cloning isn't going to change
in the near future prehaps we should move on to talking about how to fix
up the vtl so it can stream fast enough.

-----Original Message-----
From: EMC NetWorker discussion [mailto:NETWORKER AT LISTSERV.TEMPLE DOT EDU] On
Behalf Of Tim Verbois
Sent: Friday, 25 January 2008 5:38 PM
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Subject: Re: [Networker] Cloning parallelism

Because 1 drive reads from 5 disks, and 2 drives (if the volumes are on other disks and that chance is very high) read from 10 disks.

A Darren Dunham wrote:
On Thu, Jan 24, 2008 at 08:19:25AM +0100, Tim Verbois wrote:
Yaron,

1 drive gives 70 MB/s, the whole VTL has a top speed of 300 MB/s.  So

when we could read from 2 drives and write it to 1 LTO3 drive, it
should
increase the speed with at least 30 MB/s for data that is
compressable
(like file server data, we have a lot of that).
That's the bit I don't understand.  It's a VTL.  Why should reading
from
two "drives" be significantly faster than reading from one?  If it's
all
coming from disk, why the speed increase?



--
Tim Verbois
Unix Team
EDS-Telindus
02/553.71.73

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