Networker

Re: [Networker] Cloning parallelism

2008-01-25 01:46:56
Subject: Re: [Networker] Cloning parallelism
From: Tim Verbois <Tim.Verbois AT ET.VLAANDEREN DOT BE>
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Date: Fri, 25 Jan 2008 07:38:28 +0100
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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