Re: 3ware 9650SE-16ML w/XFS & RAID6: first impressions

From: Hans-Peter Jansen
Date: Sun Dec 07 2008 - 07:56:23 EST

Am Mittwoch, 3. Dezember 2008 schrieb Justin Piszcz:
> For read speed, it appears that there is some overhead (2x). With
> software raid6 I used to get 1.0Gbyte/sec read speed, or at least
> 800MiB/s across the entire array, now I only get 538MiB/s across the
> entire array. However, write speed is improved. Before it was in the mid
> 400s for RAID6 and peaking at 502MiB/s at the outer edge of the drives.
> For the write speed now, its around 620-640MiB/s at the end of the array
> and 580-620MiB/s going in further and 502MiB/s across the entire array. I
> always heard all of the horror stories with 3ware cards, it turns out
> they're not so bad after all.

Hustin, if you're after speed, AND sane support, you may consider trying
Areca products. I'm biased, since 3ware fed me up completely, when it came
to a single drive failure in a RAID 5 setup: the support only provides an
ugly web interface: when posting my problem, they replied with:

Thank you for contacting 3ware Technical Support.
Your submission has been received and assigned case id # xxxxxxxxxxxxxx. You
will receive a response within one business day.

Do not reply to this email ( websupport@xxxxxxxxxxxxxx ). Emails sent to
websupport@xxxxxxxxxxxxxx will not receive a response.
To check the status of your case, go to and login.

Thank you indeed!

Well, they responded within 23-26 hours on average, only to request
information, that was given in the very first post! In the end (a week
later) they concluded: the problem cannot be solved without replacing the
firmware and reinstalling the array! The array couldn't be restored from
degraded mode - they blamed the samsung drives for it.

Since then I replaced all my 3ware controllers with Areca controllers and
haven't regretted it, but I haven't done any serious measurement (I mostly
care for reliability, btw) but they where noticably faster.

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