Subject: Re: twe status queries?
To: Frank Naumann <firstname.lastname@example.org>
From: None <email@example.com>
Date: 12/02/2005 12:12:36
In message <Pine.NEB.firstname.lastname@example.org>Frank Naumann writes
>> However, I'm seeing a tremendous performance difference between ld0 and
>> ld1. I have a disk exerciser program; when I run it on ld0, it runs at
>> a particular speed; on ld1 - in the same way - it runs at about 15% of
>> that speed. Yes, that's 3/20 the speed - almost an order of magnitude.
>> At first I thought it might be that ld0 had priority over ld1, because
>> they were running simultaneously, but when the ld0 run finished, the
>> ld1 run didn't speed up any.
>What exact escalade raid controller do you have? The performance
>difference is normal for the escalade 7000/8000 series. This is because
>Raid5 is accelerated by the so called R5 fusion technology on this
>controller (hardware XOR engine or something like that). The problem is
>that the escalade 7000/8000 can only accelerate one Raid5 array with this
>technology (so additional Raid5 arrays are much slower). Btw. this is
>mentioned in detail somewhere in the escalade users manual.
I find that a fascinating detail. Do you know of a comparable (12-port
or more) escalde series which can support 12-drive or greater configs,
and which also offers at least one of:
a) supports 2 or more RAID-5 sets with performance not less
than the `fast' set of der Mouse's setup (multiple hardware XOR engines,
or sharing a fater engine amongst multiple RAID sets?); or
b) Supports single RAID sets larger than 2TB?