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I know this thread is about dead, but since I've spent the first part of this
week pulling my hair and dealing with Dell PERC3 issues, I'd like to quickly
throw my 2 cents in.
Quoting Jacob Coby <jcoby@xxxxxxxxxxxxxxx>:
> >From what I understand, the Megaraid driver is less than reliable. We have
> three servers running on AACRAID (two 2450s and one 2650) that have been
> plenty reliable -- not a single h/w failure, oops, or malfunction that could
> be attributed to the dell hardware in 3 years. Most (if not all) of the
> major Linux distros provide support for the AACRAID, and it generally just
> works.
The Adaptec AACRAID based cards work fine until you have heavy disk I/O, then
the entire array freezes and you must reboot. Something about a buffer
overflow with the lastest (at the last time I tried) RedHat9 drivers. Haven't
tried with RHEL.
> We also have one 1750 with the PERC4/Di, based on the Megaraid chipset. It
...
> you'll find all sorts of stories like this, and some stories of array
> corruption. There are also some reports of the Megaraid chipset being slow.
> I get pretty decent performance out of it [3].
The PERC4 cards are supposed to be better than the PERC3 - aside from the
160/320 difference. I just bought a 2650 with PERC3/QC (Megaraid) card and a
Dell 220S disk array for an Oracle 9i database. While completely stable using
RHEL or WhiteboxLinux, default RAID10 performance was HORRIBLE - <10MB/s READS
& WRITES on ten 15k drives. However, a few tweaks of the OS and RAID config,
and it's a screamer and passed all performance and load tests with flying
colors.
With the exception of th AACRAID PERC cards, all PERC3/4 issues I've seen
(RH9,RHEL) have been due to OS or RAID misconfigurations. Oh, and by the way,
there is a Megaraid2 driver that works perfectly - in my experience. If you're
running RHEL, it's already installed as a module, but megaraid(1) is used by
default. Just change your modules.conf to use the newer driver.
My 2 cents. :-)
-Ken
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