Обсуждение: 3ware vs Areca

On Fri, Jul 11, 2008 at 7:26 AM, Jeff <threshar@torgo.978.org> wrote:
> I've got a couple boxes with some 3ware 9550 controllers, and I'm less than
> pleased with performance on them.. Sequential access is nice, but start
> seeking around and you kick it in the gut.  (I've found posts on the
> internets about others having similar issues).  My last box with a 3ware I
> simply had it in jbod mode and used sw raid and it smoked the hw.
> Anyway, anybody have experience in 3ware vs Areca - I've heard plenty of
> good anecdotal things that Areca is much better, just wondering if anybody
> here has firsthand experience.    It'll be plugged into about 8 10k rpm sata
> disks.

What RAID level are you using?  How much cache do you have?  Write
back / battery backed? What OS and version?

Everything I've heard sys they're both fast performers.

I've got a couple boxes with some 3ware 9550 controllers, and I'm less than pleased with performance on them.. Sequential access is nice, but start seeking around and you kick it in the gut.  (I've found posts on the internets about others having similar issues).  My last box with a 3ware I simply had it in jbod mode and used sw raid and it smoked the hw.

Anyway, anybody have experience in 3ware vs Areca - I've heard plenty of good anecdotal things that Areca is much better, just wondering if anybody here has firsthand experience.    It'll be plugged into about 8 10k rpm sata disks. 

thanks
 
--
Jeff Trout <jeff@jefftrout.com>
http://www.stuarthamm.net/
http://www.dellsmartexitin.com/

On Fri, Jul 11, 2008 at 8:59 AM, Luke Lonergan <llonergan@greenplum.com> wrote:
> The Arecas are a lot faster than the 9550, more noticeable with disk counts
> from 12 on up.  At 8 disks you may not see much difference.
>
> The 3Ware 9650 is their answer to the Areca and it put the two a lot closer.

Do you mean the areca 12xx series or the newer 1680?  I was under the
impression the difference in performance wasn't that big between teh
95xx 3wares and teh 12xx Arecas.  We have a 1680i on order, with 16
15K RPM SAS drives.  I'll let you guys know how it runs.

> FWIW – we got some Arecas at one point and had trouble getting them
> configured and working properly.

I've heard the SAS/SATA Arecas don't get along well with some SATA
drives, but generally are quite reliable on SAS.  this was in a number
of forum posts on different hardware and linux sites repeated by
different folks over and over.

On Fri, 11 Jul 2008, Jeff wrote:

> I've got a couple boxes with some 3ware 9550 controllers, and I'm less than
> pleased with performance on them.. Sequential access is nice, but start
> seeking around and you kick it in the gut.  (I've found posts on the
> internets about others having similar issues).

Yeah, there's something weird about those controllers, maybe in how stuff
flows through the cache, that makes them slow in a lot of situations.
The old benchmarks at
http://tweakers.net/reviews/557/21/comparison-of-nine-serial-ata-raid-5-adapters-pagina-21.html
show their cards acting badly in a lot of situations and I haven't seen
anything else since vindicating the 95XX models from them.

> My last box with a 3ware I simply had it in jbod mode and used sw raid
> and it smoked the hw.

That is often the case no matter which hardware controller you've got,
particularly in more complicated RAID setups.  You might want to consider
that a larger lesson rather than just a single data point.

> Anyway, anybody have experience in 3ware vs Areca - I've heard plenty of good
> anecdotal things that Areca is much better, just wondering if anybody here
> has firsthand experience.    It'll be plugged into about 8 10k rpm sata
> disks.

Areca had a pretty clear performance lead for a while there against
3ware's 3500 series, but from what I've been reading I'm not sure that is
still true in the current generation of products.  Check out the pages
starting at
http://www.tomshardware.com/reviews/SERIAL-RAID-CONTROLLERS-AMCC,1738-12.html
for example, where the newer Areca 1680ML card just gets crushed at all
kinds of workloads by the AMCC 3ware 9690SA.  I think the 3ware 9600
series cards have achieved or exceeded what Areca's 1200 series was
capable of, while Areca's latest generation has slipped a bit from the
previous one.

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD

On Fri, Jul 11, 2008 at 12:21 PM, Greg Smith <gsmith@gregsmith.com> wrote:
> On Fri, 11 Jul 2008, Jeff wrote:
>
>> I've got a couple boxes with some 3ware 9550 controllers, and I'm less
>> than pleased with performance on them.. Sequential access is nice, but start
>> seeking around and you kick it in the gut.  (I've found posts on the
>> internets about others having similar issues).
>
> Yeah, there's something weird about those controllers, maybe in how stuff
> flows through the cache, that makes them slow in a lot of situations. The
> old benchmarks at
> http://tweakers.net/reviews/557/21/comparison-of-nine-serial-ata-raid-5-adapters-pagina-21.html
> show their cards acting badly in a lot of situations and I haven't seen
> anything else since vindicating the 95XX models from them.
>
>> My last box with a 3ware I simply had it in jbod mode and used sw raid and
>> it smoked the hw.
>
> That is often the case no matter which hardware controller you've got,
> particularly in more complicated RAID setups.  You might want to consider
> that a larger lesson rather than just a single data point.
>
>> Anyway, anybody have experience in 3ware vs Areca - I've heard plenty of
>> good anecdotal things that Areca is much better, just wondering if anybody
>> here has firsthand experience.    It'll be plugged into about 8 10k rpm sata
>> disks.
>
> Areca had a pretty clear performance lead for a while there against 3ware's
> 3500 series, but from what I've been reading I'm not sure that is still true
> in the current generation of products.  Check out the pages starting at
> http://www.tomshardware.com/reviews/SERIAL-RAID-CONTROLLERS-AMCC,1738-12.html
> for example, where the newer Areca 1680ML card just gets crushed at all
> kinds of workloads by the AMCC 3ware 9690SA.  I think the 3ware 9600 series
> cards have achieved or exceeded what Areca's 1200 series was capable of,
> while Areca's latest generation has slipped a bit from the previous one.

From my experience, the Areca controllers are difficult to operate.
Their firmware is, frankly, garbage.  In more than one instance we
have had the card panic when a disk fails, which is obviously counter
to the entire purpose of a RAID.  We finally removed the Areca
controllers from our database server and replaced them with HP P800s.

-jwb

On Fri, 11 Jul 2008, Jeff wrote:

> Yeah, it'd be fun to run more benchmarks, but the beefy box, for some reason,
> is a prod box busy 24/7.  no time to nuke it and fidgit :)

If you've got an existing array and you want to switch to another
controller, that may not work without nuking no matter what.  One other
reason to consider software RAID on top of a hardware controller running
JBOD mode is that there's no standard for how striping/mirroring is done,
so you can't just move a set of RAID disks to another brand of controller
normally.  That's no problem with software RAID.

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD

On Fri, 11 Jul 2008, Jeffrey Baker wrote:

> Their firmware is, frankly, garbage.  In more than one instance we
> have had the card panic when a disk fails, which is obviously counter
> to the entire purpose of a RAID.  We finally removed the Areca
> controllers from our database server and replaced them with HP P800s.

Can you give a bit more detail here?  If what you mean is that the driver
for the card generated an OS panic when a drive failed, that's not
necessarily the firmware at all.  I know I had problems with the Areca
cards under Linux until their driver went into the mainline kernel in
2.6.19, all kinds of panics under normal conditions.  Haven't seen
anything like that with later Linux kernels or under Solaris 10, but then
again I haven't had a disk failure yet either.

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD

On Tue, 15 Jul 2008, Jeffrey Baker wrote:

> But most recently in my memory we had an Areca HBA which, when one of
> its WD RE-2 disks failed, completely stopped responding to both the
> command line and the web management interface.

What operating system/kernel version are you using on these systems?

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD

On Mon, Jul 14, 2008 at 9:13 PM, Greg Smith <gsmith@gregsmith.com> wrote:
> On Fri, 11 Jul 2008, Jeffrey Baker wrote:
>
>> Their firmware is, frankly, garbage.  In more than one instance we
>> have had the card panic when a disk fails, which is obviously counter
>> to the entire purpose of a RAID.  We finally removed the Areca
>> controllers from our database server and replaced them with HP P800s.
>
> Can you give a bit more detail here?  If what you mean is that the driver
> for the card generated an OS panic when a drive failed, that's not
> necessarily the firmware at all.  I know I had problems with the Areca cards
> under Linux until their driver went into the mainline kernel in 2.6.19, all
> kinds of panics under normal conditions.  Haven't seen anything like that
> with later Linux kernels or under Solaris 10, but then again I haven't had a
> disk failure yet either.

Well, it is difficult to tell if the fault is with the hardware or the
software.  No traditional kernel panic has been observed.  But most
recently in my memory we had an Areca HBA which, when one of its WD
RE-2 disks failed, completely stopped responding to both the command
line and the web management interface.  Then, i/o to that RAID became
increasingly slower, and slower, until it stopped serving i/o at all.
At that point it was not relevant that the machine was technically
still running.

We have another Areca HBA that starts throwing errors up the SCSI
stack if it runs for more than 2 months at a time.  We have to reboot
it on a schedule to keep it running.

-jwb

On Tue, Jul 15, 2008 at 8:17 AM, Greg Smith <gsmith@gregsmith.com> wrote:
> On Tue, 15 Jul 2008, Jeffrey Baker wrote:
>
>> But most recently in my memory we had an Areca HBA which, when one of its
>> WD RE-2 disks failed, completely stopped responding to both the command line
>> and the web management interface.
>
> What operating system/kernel version are you using on these systems?

Debian "etch", which has a 2.6.18 kernel.  I have contacted Areca
support (as well as the linux-scsi mailing list) and their responses
are usually either 1) upgrade the driver and/or firmware even though I
have the latest drivers and firmware, or 2) vague statements about the
disk being incompatible with the controller.

-jwb

Jeffrey Baker writes:

> Their firmware is, frankly, garbage.  In more than one instance we
> have had the card panic when a disk fails, which is obviously counter
> to the entire purpose of a RAID.

I have had simmilar problems with 3ware 9550 and 9650 cards.
Undre FreeBSD I have seen constant crashes under heavy loads.
Used to think it was just FreeBSD, but saw a thread on StorageReview where
the same was happening under Linux.

> controllers from our database server and replaced them with HP P800s.

How is that working out?
Which RAID level? SAS/SATA?

On Tue, 15 Jul 2008, Jeffrey Baker wrote:

> Debian "etch", which has a 2.6.18 kernel.  I have contacted Areca
> support (as well as the linux-scsi mailing list) and their responses
> are usually either 1) upgrade the driver and/or firmware even though I
> have the latest drivers and firmware

Well, technically you don't have the latest driver, because that's the one
that comes with the latest Linux kernel.  I'm guessing you have RHEL5 here
from that fact that you're using 2.6.18.  I have a CentOS5 system here
with an Areca card in it.  It installed it initially with the stock 2.6.18
kernel there but it never worked quite right; all sorts of odd panics
under heavy load.  All my problems went away just by moving to a generic
2.6.22, released some time after the Areca card became of more first-class
citizen maintained actively by the kernel developers themselves.

> 2) vague statements about the disk being incompatible with the
> controller.

That sort of situation is unfortunate but I don't feel it's unique to
Areca.  There's lots of reasons why some manufacturers end up with drives
that don't work well with some controllers, and it is hard to assign blame
when it happens.  There is something to be said for buying more integrated
and tested systems; ultimately if you build stuff from parts, you're kind
of stuck being the QA and that process presumes that you may discover
incompatible combinations and punt them out in place of ones that do.

--
* Greg Smith gsmith@gregsmith.com http://www.gregsmith.com Baltimore, MD