ADSM-L

Re: backup performance with db and log on a SAN

2002-09-02 11:09:40
Subject: Re: backup performance with db and log on a SAN
From: Remco Post <r.post AT SARA DOT NL>
To: ADSM-L AT VM.MARIST DOT EDU
Date: Mon, 2 Sep 2002 15:17:24 +0200
On maandag, september 2, 2002, at 01:49 , Daniel Sparrman wrote:

Hi Eliza

As I understand it, each "tape-HBA" has 3 3590E FC connnected to it. The
two 21G database disks, are each connected to it's own HBA?

According to spec sheets, the 3590E FC could handle speed up to 100MB/s
with 3:1 compression. This means that with 3 drives, you could have up
to
300MB/s. However, the HBA will only theoretically handle 125MB/s, or
250MB/s with 2Gb FC.

Fortunately, an 3590E will do only about 16MB/s or so, so 3 drives will
not fill up a FC link.... 3:1 compression is very rare in my experience,
2:1 or less is far more likely...


---
Met vriendelijke groeten,

Remco Post

SARA - Stichting Academisch Rekencentrum Amsterdam    http://www.sara.nl
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