Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Michael Evans]

The SUPERMICRO AOC-SASLP-MV8 PCI Express x4 Low Profile SAS SAS RAID
Controller seems to fit my needs and budget except for one glaring
omission on Supermicro's product page, and every other site that
blindly copies it.

Has anyone tested this hardware with a 48-bit LBA required drive (EG
one of the 3TB drives that still exposes 512k sectors)?


The other question, which is more on topic for linux-raid, is related
to current driver support.  I understand that the drivers have greatly
matured since the last time I saw the card discussed in the list.
With recent kernels have all the older issues been resolved?


Thank you,

Michael

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Stan Hoeppner]

Michael Evans put forth on 1/21/2011 10:00 AM:
> The SUPERMICRO AOC-SASLP-MV8 PCI Express x4 Low Profile SAS SAS RAID
> Controller seems to fit my needs and budget except for one glaring
> omission on Supermicro's product page, and every other site that
> blindly copies it.
> 
> Has anyone tested this hardware with a 48-bit LBA required drive (EG
> one of the 3TB drives that still exposes 512k sectors)?

NewEgg has an excellent return policy:
http://www.newegg.com/Product/Product.aspx?Item=N82E16816101358

But, BTW, if you can afford over $1000 of 3TB drives, why are you demanding to
go so cheap with the HBA?  There are plenty of much better LSI based dual
SFF8087 HBAs available with no LBA or driver issues.  For instance:
http://www.newegg.com/Product/Product.aspx?Item=N82E16816117157

$155 Quality/compatible LSI SAS1068E chip+driver vs
$109 Marvell 88SE6480 less than quality chip+driver

If you can afford 5+ 3TB drives you can certainly afford an extra ~$50 for a
decent quality known to work SAS/SATA HBA.  I say 5+ because you're obviously
starting out with 5 or you'd be looking at cards with a single SFF8087, or
simply 4 individual SATA connectors.

I can't imagine an easier decision to make:  $50 for guaranteed piece of mind,
performance, compatibility.

-- 
Stan

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Michael Evans]

On Fri, Jan 21, 2011 at 11:04 AM, Stan Hoeppner <stan@hardwarefreak.com> wrote:
> Michael Evans put forth on 1/21/2011 10:00 AM:
>> The SUPERMICRO AOC-SASLP-MV8 PCI Express x4 Low Profile SAS SAS RAID
>> Controller seems to fit my needs and budget except for one glaring
>> omission on Supermicro's product page, and every other site that
>> blindly copies it.
>>
>> Has anyone tested this hardware with a 48-bit LBA required drive (EG
>> one of the 3TB drives that still exposes 512k sectors)?
>
> NewEgg has an excellent return policy:
> http://www.newegg.com/Product/Product.aspx?Item=N82E16816101358
>
> But, BTW, if you can afford over $1000 of 3TB drives, why are you demanding to
> go so cheap with the HBA?  There are plenty of much better LSI based dual
> SFF8087 HBAs available with no LBA or driver issues.  For instance:
> http://www.newegg.com/Product/Product.aspx?Item=N82E16816117157
>
> $155 Quality/compatible LSI SAS1068E chip+driver vs
> $109 Marvell 88SE6480 less than quality chip+driver
>
> If you can afford 5+ 3TB drives you can certainly afford an extra ~$50 for a
> decent quality known to work SAS/SATA HBA.  I say 5+ because you're obviously
> starting out with 5 or you'd be looking at cards with a single SFF8087, or
> simply 4 individual SATA connectors.
>
> I can't imagine an easier decision to make:  $50 for guaranteed piece of mind,
> performance, compatibility.
>
> --
> Stan
> --
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> the body of a message to majordomo@vger.kernel.org
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>

I wouldn't mind spending an extra $50 on the controller IF I knew it
supported 48 or 64 bit LBA, however neither the documentation on Intel
and NewEgg specifies what is supported.  In fact I have to assume
PCI-E 1.0 since it doesn't specify (not that it's an issue, 8 lane 1x
vs 4 lane 2x is more or less the same thing; though 4x is more future
proof since there is likely to be a slot that big on future
motherboards at /least/ for physics GPU support).

Are you suggesting the LSI based Intel card because you know it to
properly support >32 bit LBA?
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Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Stan Hoeppner]

Michael Evans put forth on 1/21/2011 11:50 PM:

> I wouldn't mind spending an extra $50 on the controller IF I knew it
> supported 48 or 64 bit LBA, however neither the documentation on Intel

No product descriptions list 48 bit LBA because ALL SAS/SATA devices and HbAs
since ATA-6 (around 2003) natively support 48 bit LBA.  LBA48 is what got us
past the 137GB barrier.  The industry jumped from 28 bit LBA straight to 48 bit
LBA.  Google will show you this information in about 0.5 seconds.  I'll save you
those 0.5s:  http://www.48bitlba.com/

> and NewEgg specifies what is supported.  In fact I have to assume
> PCI-E 1.0 since it doesn't specify (not that it's an issue, 8 lane 1x
> vs 4 lane 2x is more or less the same thing; though 4x is more future
> proof since there is likely to be a slot that big on future
> motherboards at /least/ for physics GPU support).

It doesn't matter what card you choose, either x4 or x8, PCIe 1.0, 2.0, or 3.0.
 They all have plenty of b/w, all support 48bit LBA, and someone, somewhere,
makes a motherboard with all the slots of the size/type mix you need to fit the
specific PCIe 'width' cads you buy.  "Desktop" style boards are probably more
likely not to have PCIe x8 slots, but to have mostly x1 slots and maybe a single
x4 slots.  Server boards are more likely to have multiple x8 and x4 slots.
However, many desktop boards have multiple x16 slots into which you can install
and x8 or an x4 unless you really _need_ two, three, or 4 GPU cards.

> Are you suggesting the LSI based Intel card because you know it to
> properly support >32 bit LBA?

I know it supports 48 bit LBA in SATA mode and 64 bit LBA in SAS mode.  However,
so does the SuperMicro Marvell based HBA.  I recommend the Intel/LSI HBA simply
because it's a higher quality SAS chip, it'll give better performance, and you
won't have any potential driver headaches with it as you may with the Marvell
based card.

If your time is worth $25/hour, two hours wasted fighting an issue with the
Marvell chip/driver combo bought you the Intel/LSI HBA in the first place.  If
your time is worth nothing and you enjoy pulling hair out, go with the $50
cheaper Marvell based solution.  And, once again, if you're going to spend $1000
on drives, what an extra $50 for a good HBA for them?

It seems from reading your posts that this is a "dream" system you've been
_thinking_ about building for a few years now, and isn't something you're
actually going to build.  Even if this is simply an exercise in mental
masturbation, I'm glad to have spent the time on this thread if merely to
educate you about ATA, SATA, SAS, specifically WRT LBA, and the difference
between quality HBAs/storage chip and low quality HBAs/storage chips.

-- 
Stan

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Michael Evans]

On Sat, Jan 22, 2011 at 8:04 AM, Stan Hoeppner <stan@hardwarefreak.com> wrote:
> Michael Evans put forth on 1/21/2011 11:50 PM:
>
>> I wouldn't mind spending an extra $50 on the controller IF I knew it
>> supported 48 or 64 bit LBA, however neither the documentation on Intel
>
> No product descriptions list 48 bit LBA because ALL SAS/SATA devices and HbAs
> since ATA-6 (around 2003) natively support 48 bit LBA.  LBA48 is what got us
> past the 137GB barrier.  The industry jumped from 28 bit LBA straight to 48 bit
> LBA.  Google will show you this information in about 0.5 seconds.  I'll save you
> those 0.5s:  http://www.48bitlba.com/

Thank you, /that/ was the missing part of the picture; that ATA-6
required support for it.

Ironically I'd seen most of the result articles on Wikipedia, but was
expecting something like that in a place other than the very top
paragraph.  I was looking for some kind of table that specifically
associated a standard with relevant minimal requirements.  I'm also
very glad that I asked here first since I would have just gone with
the better sounding hardware (4x PCI-e 2.0) over the more reliable and
closely priced older hardware (the 8x PCI-e 1.0).

Also, you are half right about this being a 'dream' system.  For years
I've been using a carefully selected 6 port motherboard, and 3 PCI-e
1x cards to get a total of 12 ports.  However I'm looking to rebuild
that aging system and now that I have the proper funds want to do it
with more reliable hardware.  I wanted to buy an adapter that would
last until whatever standard comes out in another decade or so and
handle any drives that might come on the market within that time.
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Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Matt Garman]

Another way to get an LSI SAS 1068 based card is the IBM ServeRAID
BR10i, discussed in detail here:

    http://www.servethehome.com/ibm-serveraid-br10i-lsi-sas3082e-r-pciexpress-sas-raid-controller/

I bought two off ebay for $50 US.

The only caveat with these LSI SAS1068 cards is a driver bug that pops
up when using smartd on drives connected to the controller.  IIRC, the
bug was fixed in kernel version 2.6.36.  Lots of info on this on the
web and the list archives.

-Matt

On Sat, Jan 22, 2011 at 2:36 PM, Michael Evans <mjevans1983@gmail.com> wrote:
> On Sat, Jan 22, 2011 at 8:04 AM, Stan Hoeppner <stan@hardwarefreak.com> wrote:
>> Michael Evans put forth on 1/21/2011 11:50 PM:
>>
>>> I wouldn't mind spending an extra $50 on the controller IF I knew it
>>> supported 48 or 64 bit LBA, however neither the documentation on Intel
>>
>> No product descriptions list 48 bit LBA because ALL SAS/SATA devices and HbAs
>> since ATA-6 (around 2003) natively support 48 bit LBA.  LBA48 is what got us
>> past the 137GB barrier.  The industry jumped from 28 bit LBA straight to 48 bit
>> LBA.  Google will show you this information in about 0.5 seconds.  I'll save you
>> those 0.5s:  http://www.48bitlba.com/
>
> Thank you, /that/ was the missing part of the picture; that ATA-6
> required support for it.
>
> Ironically I'd seen most of the result articles on Wikipedia, but was
> expecting something like that in a place other than the very top
> paragraph.  I was looking for some kind of table that specifically
> associated a standard with relevant minimal requirements.  I'm also
> very glad that I asked here first since I would have just gone with
> the better sounding hardware (4x PCI-e 2.0) over the more reliable and
> closely priced older hardware (the 8x PCI-e 1.0).
>
> Also, you are half right about this being a 'dream' system.  For years
> I've been using a carefully selected 6 port motherboard, and 3 PCI-e
> 1x cards to get a total of 12 ports.  However I'm looking to rebuild
> that aging system and now that I have the proper funds want to do it
> with more reliable hardware.  I wanted to buy an adapter that would
> last until whatever standard comes out in another decade or so and
> handle any drives that might come on the market within that time.
> --
> To unsubscribe from this list: send the line "unsubscribe linux-raid" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
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Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Spelic]

On 01/22/2011 09:36 PM, Michael Evans wrote:
>
> Also, you are half right about this being a 'dream' system.  For years
> I've been using a carefully selected 6 port motherboard, and 3 PCI-e
> 1x cards to get a total of 12 ports.

So you are trying to reach 12 ports?
C'mon don't be cheap, there are lightning-fast 16-ports HBA controllers 
from LSI, at 6.0gbit/sec, $350 or so. $25 per port is not much; it is 
much less than the cost of the disk you are attaching to it.
This frees you from the choice of the mainboard, and this is important, 
firstly because you can save $$$ in there, and secondly because if the 
mainboard fails, what are you going to do? you are going to buy another 
one with 6 ports? Difficult to find... and expensive also.
Also using 2 different controllers for your disks (part from mainboard, 
part from addon card) is a bit of pain in the *** for administration 
things, also performances would be the slowest of the two for every request.

> However I'm looking to rebuild
> that aging system and now that I have the proper funds want to do it
> with more reliable hardware.  I wanted to buy an adapter that would
> last until whatever standard comes out in another decade or so and
> handle any drives that might come on the market within that time.
>    

Right so you need 6.0gbit/sec

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Andre Tomt]

On 01/23/2011 12:40 AM, Spelic wrote:
> On 01/22/2011 09:36 PM, Michael Evans wrote:
>>
>> Also, you are half right about this being a 'dream' system. For years
>> I've been using a carefully selected 6 port motherboard, and 3 PCI-e
>> 1x cards to get a total of 12 ports.
>
> So you are trying to reach 12 ports?
> C'mon don't be cheap, there are lightning-fast 16-ports HBA controllers
> from LSI, at 6.0gbit/sec, $350 or so. $25 per port is not much; it is
> much less than the cost of the disk you are attaching to it.
> This frees you from the choice of the mainboard, and this is important,
> firstly because you can save $$$ in there, and secondly because if the
> mainboard fails, what are you going to do? you are going to buy another
> one with 6 ports? Difficult to find... and expensive also.
> Also using 2 different controllers for your disks (part from mainboard,
> part from addon card) is a bit of pain in the *** for administration
> things, also performances would be the slowest of the two for every
> request.

Since we're talking about "non hardware raid" usage, I don't really 
understand how it would be harder to manage mixed controllers? Care to 
explain? I can't quite get the performance statement to compute, 
either.. Its not like the same I/O goes out to all controllers. If your 
other controller is slower, just put fewer drives on it. Balance it out.

Anyways, If you settle for SATA and a desktop motherboard, most mid to 
high end s1156/1155 motherboards nowadays are fitted with 6 to 8 SATA 
ports. They're in now way hard to come by - even 8 ports seems to be 
available at $130 (I spent 10 seconds looking on newegg). But then again 
not all of them will *boot* off 3TB drives - at least many of the 1156 ones.

As for on board performance, integrated Intel ICH's AHCI controllers 
tend to top out at around 750MB/s aggregate. 6 ports are usually on the 
Intel, the rest on some AHCI compatible chip from Marvell. In general 
you can expect around 1GB/s aggregated from the on board controllers at 
the same time on a standard socket 1156/1155 desktop class intel chipset 
based motherboard.

Regarding the AOC-SASLP-MV8, yes, they're not worth it - the mvsas 
driver is still buggy when used with SATA. I have heaps of issues with 
mine - at least when using Seagate 7200.11 1.5TB drives on 2.6.36.3. 
Keeps stalling and throwing IO errors (no corruption yet, though). The 
card also tops out at ~700MB/s aggregate - and we can't have any of that 
can we ;-)

So yeah, the LSI based cards are seems like a good bet if you go the SAS 
HBA route. Even the previous 3Gb/s generation can do a cool 
1600-1700MB/s if you give them 8 pcie lanes. If he ever plan to expand 
into expander (he he) territory, that bandwidth is good to have. Well, 
in a "dream system" anyway, any normal workloads are generally more 
random and much, much lower in throughput. But hey, we're going for 
bragging rights here, right? :-)

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Michael Evans]

On Sat, Jan 22, 2011 at 6:44 PM, Andre Tomt <andre@tomt.net> wrote:
> On 01/23/2011 12:40 AM, Spelic wrote:
>>
>> On 01/22/2011 09:36 PM, Michael Evans wrote:
>>>
>>> Also, you are half right about this being a 'dream' system. For years
>>> I've been using a carefully selected 6 port motherboard, and 3 PCI-e
>>> 1x cards to get a total of 12 ports.
>>
>> So you are trying to reach 12 ports?
>> C'mon don't be cheap, there are lightning-fast 16-ports HBA controllers
>> from LSI, at 6.0gbit/sec, $350 or so. $25 per port is not much; it is
>> much less than the cost of the disk you are attaching to it.
>> This frees you from the choice of the mainboard, and this is important,
>> firstly because you can save $$$ in there, and secondly because if the
>> mainboard fails, what are you going to do? you are going to buy another
>> one with 6 ports? Difficult to find... and expensive also.
>> Also using 2 different controllers for your disks (part from mainboard,
>> part from addon card) is a bit of pain in the *** for administration
>> things, also performances would be the slowest of the two for every
>> request.
>
> Since we're talking about "non hardware raid" usage, I don't really
> understand how it would be harder to manage mixed controllers? Care to
> explain? I can't quite get the performance statement to compute, either..
> Its not like the same I/O goes out to all controllers. If your other
> controller is slower, just put fewer drives on it. Balance it out.
>
> Anyways, If you settle for SATA and a desktop motherboard, most mid to high
> end s1156/1155 motherboards nowadays are fitted with 6 to 8 SATA ports.
> They're in now way hard to come by - even 8 ports seems to be available at
> $130 (I spent 10 seconds looking on newegg). But then again not all of them
> will *boot* off 3TB drives - at least many of the 1156 ones.
>
> As for on board performance, integrated Intel ICH's AHCI controllers tend to
> top out at around 750MB/s aggregate. 6 ports are usually on the Intel, the
> rest on some AHCI compatible chip from Marvell. In general you can expect
> around 1GB/s aggregated from the on board controllers at the same time on a
> standard socket 1156/1155 desktop class intel chipset based motherboard.
>
> Regarding the AOC-SASLP-MV8, yes, they're not worth it - the mvsas driver is
> still buggy when used with SATA. I have heaps of issues with mine - at least
> when using Seagate 7200.11 1.5TB drives on 2.6.36.3. Keeps stalling and
> throwing IO errors (no corruption yet, though). The card also tops out at
> ~700MB/s aggregate - and we can't have any of that can we ;-)
>
> So yeah, the LSI based cards are seems like a good bet if you go the SAS HBA
> route. Even the previous 3Gb/s generation can do a cool 1600-1700MB/s if you
> give them 8 pcie lanes. If he ever plan to expand into expander (he he)
> territory, that bandwidth is good to have. Well, in a "dream system" anyway,
> any normal workloads are generally more random and much, much lower in
> throughput. But hey, we're going for bragging rights here, right? :-)
>

Oh I'm extremely frugal.  I typically wind up going with AMD chipped
systems since they support all the nice CPU features across everything
(well, I don't know about semprons, but honestly spend a tiny bit more
for a dual core).  Sure they've not been the most power efficient
since the Core architecture came out, but they're still priced so that
they offer excellent results dollar for dollar.

The number of ports is more in relation to the cost per gigabyte
sweetspot and what I can spare on storage.  Currently said sweetspot
seems to be 2TB drives, if I were to buy RIGHT now I'd go for a
Samsung Spinpoint F4 since IIRC out of Seagate, WD, and Samsung only
Samsung still enables scterc to alter the timeout/recovery time.

As it's a personal array for everything (data backups, networked media
storage for set top boxes, etc) I don't really need killer
performance; once I saturate the gigabit link I'm happy that way.
What I really need is a good way of using raid6 to get the most cost
effective volume of storage while still tolerating failure.

I'm more interested in waiting for the 3TB drives to migrate down to
the 100-150 range though; support for even larger drives is something
I'll need in an upgrade cycle or two (which is still within my planned
lifespan for the card).

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Spelic]

On 01/23/2011 03:44 AM, Andre Tomt wrote:
>
> Since we're talking about "non hardware raid" usage, I don't really 
> understand how it would be harder to manage mixed controllers? Care to 
> explain? 

Well, yeah, probably I have exxagerated. If you need to replace a drive 
you have to associate the drive letter to the hardware slot, and if you 
have two controllers you have to remember two mappings. Also you have to 
know the idiosincracies of 2 controllers, like, do they support hot swap 
or they freeze? Do the support smartmontools well or not, are both 
capable of withstanding high IOPS situation or one drops out and 
degrades the array... but probably the OP can accept these drawbacks.

> I can't quite get the performance statement to compute, either.. Its 
> not like the same I/O goes out to all controllers. If your other 
> controller is slower, just put fewer drives on it. Balance it out.

I was thinking more to the round trip time, which will be different for 
the 2 controllers, and supposing the OP is creating an array spanning 
both controllers.

>
> Anyways, If you settle for SATA and a desktop motherboard, most mid to 
> high end s1156/1155 motherboards nowadays are fitted with 6 to 8 SATA 
> ports. They're in now way hard to come by - even 8 ports seems to be 
> available at $130 (I spent 10 seconds looking on newegg). 

I think other mainboards can cost down to $50, but I haven't checked 
recently

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Sven Eschenberg]

Would you mind explaining what you mean by mapping and why this should be
an issue? Or are you suggesting, when talking about drive letter, to still
use sdN names when handling drives? Because that seems to be somewhat from
the dark ages...


On Sun, January 23, 2011 05:00, Spelic wrote:
> On 01/23/2011 03:44 AM, Andre Tomt wrote:
>>
>> Since we're talking about "non hardware raid" usage, I don't really
>> understand how it would be harder to manage mixed controllers? Care to
>> explain?
>
> Well, yeah, probably I have exxagerated. If you need to replace a drive
> you have to associate the drive letter to the hardware slot, and if you
> have two controllers you have to remember two mappings. Also you have to
> know the idiosincracies of 2 controllers, like, do they support hot swap
> or they freeze? Do the support smartmontools well or not, are both
> capable of withstanding high IOPS situation or one drops out and
> degrades the array... but probably the OP can accept these drawbacks.
>

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Stan Hoeppner]

Michael Evans put forth on 1/22/2011 2:36 PM:

> Also, you are half right about this being a 'dream' system.  For years
> I've been using a carefully selected 6 port motherboard, and 3 PCI-e
> 1x cards to get a total of 12 ports.  However I'm looking to rebuild
> that aging system and now that I have the proper funds want to do it
> with more reliable hardware.  I wanted to buy an adapter that would
> last until whatever standard comes out in another decade or so and
> handle any drives that might come on the market within that time.

The LSI based Intel SAS HBA I mentioned, the  SASUC8I, will directly support 8
SAS/SATA drives, but using multiple SAS/SATA expanders it will support over 100
drives.  The following Intel SAS expander card is a matched partner to the SASUC8I.

http://www.newegg.com/Product/Product.aspx?Item=N82E16816117207
$280

To maximize drive count, you would directly connect 4 drives to the lower
numbered SFF8087 4 port connector with either a straight 8087 cable if you're
using a hot swap backplane with an 8087 style connector, or you'd use an 8087 to
4 SATA breakout cable if directly connecting to the drives or individual hot
swap cages.

The fun part:  You'd connect an 8087 cable from the other port on the HBA to one
of the 6 8087 connectors on the SAS expander card.  You would then connect the
remaining 5 SFF8087 ports to *20* SAS or SATA drive using the appropriate
cables.  This would give you 24 drives total.  Your aggregate bandwidth to/from
the set of 20 drives on the expander would be 1.2 GB/s full duplex or 2.4 GB/s
total.  It will be the same for the 4 direct connected drives but 4 drives
simply can't push that much data.

If you want symmetrical bandwidth for all drives, you'd simply connect both HBA
connectors to the expander, which would give you 2.4/4.8 GB/s aggregate, but
would limit you to 'only' 16 drives.  Here a are a couple rack chassis with hot
swap bays perfect for such a setup:

Inexpensive:
http://www.newegg.com/Product/Product.aspx?Item=N82E16811219039
http://www.norcotek.com/RPC-4116.php

Better quality, includes redundant PSU, twice the price:
http://www.newegg.com/Product/Product.aspx?Item=N82E16811123135
http://usa.chenbro.com/corporatesite/products_detail.php?sku=144

I've built quite a few servers over the years with Chenbro cases.  They are
excellent quality.  One of my personal servers resides in an old double wide
Chenbro pedestal chassis with 12x3.5" hot swap SCSI bays.  Been using it since
1999, not a bit of trouble with it, and it has survived 5 moves.  I've never
used the Norco products.

-- 
Stan

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Stan Hoeppner]

Maurice Hilarius put forth on 1/23/2011 5:18 PM:
> On 1/23/2011 2:24 PM, Stan Hoeppner wrote:
>> ..
>>> Chenbro backplanes do not support 6Gb SAS/SATA.
>> Considering no single (mech) drive can push 600 MB/s, let alone 300 MB/s, is
>> this really an issue?

> Yes.
> I have seen it first hand.
> If you connect 6GB drives and interfaces to it, you see a lot of errors.
> One has to be careful to set all devices to 3GB, assuming the devices have
> jumpers or other means to do so.

Which chassis model was this?

>>    Mech drives aren't even going to be surpassing 300 MB/s
>> in the foreseeable future.
>>
> Perhaps, but their buffers do, and if one uses expanders it is useful

The _real world_ application performance difference between SATA II and SATA III
mech drive interfaces is something on the order of 1%.  With SSDs a little more
as some of them can actually push data faster than 3 Gb/s.

Upstream of an expander the additional b/w is useful, not downstream.

-- 
Stan

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[John Robinson]

On 24/01/2011 01:52, Stan Hoeppner wrote:
> Maurice Hilarius put forth on 1/23/2011 5:18 PM:
[...]
>> If you connect 6GB drives and interfaces to it, you see a lot of errors.

The first PC I bought had a 6GB drive in it.

Cheers,

John.

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Mark Knecht]

On Sun, Jan 23, 2011 at 7:28 PM, John Robinson
<john.robinson@anonymous.org.uk> wrote:
> On 24/01/2011 01:52, Stan Hoeppner wrote:
>>
>> Maurice Hilarius put forth on 1/23/2011 5:18 PM:
>
> [...]
>>>
>>> If you connect 6GB drives and interfaces to it, you see a lot of errors.
>
> The first PC I bought had a 6GB drive in it.
>
> Cheers,
>
> John.

You make me feel old. I was part of the 'boot CPM from floppy' era...
5MHz and it didn't have a hard drive... ;-)

My home work machine has 2.5TB.

- Mark

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[John Robinson]

On 24/01/2011 11:27, Mark Knecht wrote:
> On Sun, Jan 23, 2011 at 7:28 PM, John Robinson
> <john.robinson@anonymous.org.uk>  wrote:
>> On 24/01/2011 01:52, Stan Hoeppner wrote:
>>> Maurice Hilarius put forth on 1/23/2011 5:18 PM:
>> [...]
>>>> If you connect 6GB drives and interfaces to it, you see a lot of errors.
>>
>> The first PC I bought had a 6GB drive in it.
>
> You make me feel old. I was part of the 'boot CPM from floppy' era...
> 5MHz and it didn't have a hard drive... ;-)

We're probably actually about the same age then; my first computer used 
cassette tape and had a 2MHz 8-bit processor. I started using 
PC-compatibles 7 or 8 years later, but didn't buy one myself for another 
6 years (that was the one with the 6GB hard drive) by which time I'd 
contributed patches to the Linux kernel, Postgres and PHP - and that was 
12 years ago now...

Cheers,

John.

RE: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Leslie Rhorer]

> -----Original Message-----
> From: linux-raid-owner@vger.kernel.org [mailto:linux-raid-
> owner@vger.kernel.org] On Behalf Of John Robinson
> Sent: Monday, January 24, 2011 5:56 AM
> To: Mark Knecht
> Cc: Linux RAID
> Subject: Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA
> questions for HW owners/users
> 
> On 24/01/2011 11:27, Mark Knecht wrote:
> > On Sun, Jan 23, 2011 at 7:28 PM, John Robinson
> > <john.robinson@anonymous.org.uk>  wrote:
> >> On 24/01/2011 01:52, Stan Hoeppner wrote:
> >>> Maurice Hilarius put forth on 1/23/2011 5:18 PM:
> >> [...]
> >>>> If you connect 6GB drives and interfaces to it, you see a lot of
> errors.
> >>
> >> The first PC I bought had a 6GB drive in it.
> >
> > You make me feel old. I was part of the 'boot CPM from floppy' era...
> > 5MHz and it didn't have a hard drive... ;-)
> 
> We're probably actually about the same age then; my first computer used
> cassette tape and had a 2MHz 8-bit processor. I started using

	Ah, that's better.  For many years, I didn't own any of the
computers I used, at all - purchasing an IBM 360 was a good bit beyond my
means.  The first "micro" on which I ever worked was a Nicolet 20 bit
rackmount with DTL logic and magnetic core memory.  The first home computer
I ever bought was a Texas Instruments 99/4a.

> PC-compatibles 7 or 8 years later, but didn't buy one myself for another
> 6 years (that was the one with the 6GB hard drive) by which time I'd
> contributed patches to the Linux kernel, Postgres and PHP - and that was
> 12 years ago now...

	Yeah, once the 80386 was introduced, I became interested in an Intel
based "clone".  I didn't like the limitations of the x86 platform - I still
don't - but its processing power, 32 bit architecture, and programming
features were sufficient to lure me into purchasing a clone.  It had an
unbelievable 1MB of memory and a vast 40 MB hard drive, with a system clock
of 16 MHz, and of course a 32 bit wide address bus and memory bus.

RE: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Leslie Rhorer]

> -----Original Message-----
> From: linux-raid-owner@vger.kernel.org [mailto:linux-raid-
> owner@vger.kernel.org] On Behalf Of John Robinson
> Sent: Sunday, January 23, 2011 9:28 PM
> To: Linux RAID
> Subject: Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA
> questions for HW owners/users
> 
> On 24/01/2011 01:52, Stan Hoeppner wrote:
> > Maurice Hilarius put forth on 1/23/2011 5:18 PM:
> [...]
> >> If you connect 6GB drives and interfaces to it, you see a lot of
> errors.
> 
> The first PC I bought had a 6GB drive in it.

	Infant.  :-)

	The first computer I bought (not a "PC") didn't have a hard drive,
at all.  The first x86 computer I ever bought (I waited for the introduction
of the 80386 before going with an x86 computer) had a 40 MB hard drive.

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Maurice Hilarius]

On 1/24/2011 3:06 PM, Leslie Rhorer wrote:
>> ..
>>>> If you connect 6GB drives and interfaces to it, you see a lot of
>> errors.
>>
>> The first PC I bought had a 6GB drive in it.
> 	Infant.  :-)
>
> 	The first computer I bought (not a "PC") didn't have a hard drive,
> at all.  The first x86 computer I ever bought (I waited for the introduction
> of the 80386 before going with an x86 computer) had a 40 MB hard drive.
>
Of course I was speaking of 6GB/Sec SAS2 drives..

Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Stan Hoeppner]

Maurice Hilarius put forth on 1/25/2011 12:30 PM:
> On 1/24/2011 3:06 PM, Leslie Rhorer wrote:
>>> ..
>>>>> If you connect 6GB drives and interfaces to it, you see a lot of
>>> errors.

> Of course I was speaking of 6GB/Sec SAS2 drives..

Capital "B" stands for BYTES.  Small "b" stands for bits.
You stated 6 GigaBYTES/sec when you meant to say 6 gigabits/sec.

Always use a BIG B when stating parallel bus data rates.  Always use small b
when stating serial interconnect data rates.  SAS and SATA are serial
interconnect technologies.

You've formed a bad habit which may be difficult to break.  Nonetheless, you
must break this habit if you want those reading your text to correctly
understand what you're saying.

-- 
Stan

RE: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA questions for HW owners/users

[Leslie Rhorer]

> -----Original Message-----
> From: linux-raid-owner@vger.kernel.org [mailto:linux-raid-
> owner@vger.kernel.org] On Behalf Of Stan Hoeppner
> Sent: Saturday, January 22, 2011 6:50 PM
> To: Michael Evans
> Cc: Linux RAID
> Subject: Re: Low cost PCI-E unRAID - Supermicro AOC-SASLP-MV8 Driver/LBA
> questions for HW owners/users

<snip>

> Inexpensive:
> http://www.newegg.com/Product/Product.aspx?Item=N82E16811219039
> http://www.norcotek.com/RPC-4116.php
> 
> Better quality, includes redundant PSU, twice the price:
> http://www.newegg.com/Product/Product.aspx?Item=N82E16811123135
> http://usa.chenbro.com/corporatesite/products_detail.php?sku=144
> 
> I've built quite a few servers over the years with Chenbro cases.  They
> are
> excellent quality.  One of my personal servers resides in an old double
> wide
> Chenbro pedestal chassis with 12x3.5" hot swap SCSI bays.  Been using it
> since
> 1999, not a bit of trouble with it, and it has survived 5 moves.  I've
> never
> used the Norco products.

	I have.  I cannot recommend Norcotek.  I had a horrendously bad
experience with one of their 12 bay SAS RAID chassis.  Their tech support
was pathetic, and despite numerous RMAs, replacing essentially every
component of the chassis, the chassis could not be made stable.  The drives
experienced all sorts of massive errors when installed in the chassis, and
it was never possible to get more than 8 drives visible.  Plugging a drive
into one slot would cause 1 or 2 drives in other slots to disappear.  I lost
the entire array several times, and suffered massive amounts of data
corruption.  I finally gave up and purchased another chassis, and all the
problems went away completely.