LSI 9240-4i 4K alignment

[Josh Paetzel]

On 08/19/2012 14:04, Steven Hartland wrote:
> 
> ----- Original Message ----- From: "Don Lewis" <truckman at FreeBSD.org>
> To: <killing at multiplay.co.uk>
> Cc: <gkontos.mail at gmail.com>; <freebsd-stable at FreeBSD.org>;
> <freebsd-hardware at FreeBSD.org>
> Sent: Sunday, August 19, 2012 6:37 PM
> Subject: Re: LSI 9240-4i 4K alignment
> 
> 
>> On 16 Aug, Steven Hartland wrote:
>>> ----- Original Message ----- From: "George Kontostanos"
>>> <gkontos.mail at gmail.com>
>>>  
>>>> You are right, the chip specs say: LSISAS2108 RAID-on-Chip
>>>>
>>>> The drives are identified as mfisyspd0, mfisyspd1, etc.
>>>
>>> The following might be interesting to you:-
>>> http://forums.servethehome.com/showthread.php?599-LSI-RAID-Controller-and-HBA-Complete-Listing-Plus-OEM-Models
>>>
>>>
>>> Which states:-
>>> LSI MegaRAID SAS 9240-4i 1x4 port internal SAS vertical,
>>> no cache, no BBU, RAID 0, 1, 10 and 5, can be crossflashed
>>> to LSI9211 IT/IR
>>>
>>> This is insteresting as this is the card we're using but
>>> in the 8 port version under mps :)
>>
>> I wish I would have known this earlier.  I just put together a ZFS
>> server using LSI MegaRAID SAS 9240-8i cards.  The cabling probably would
>> have been cleaner with the 9211-8i, but I went with the 9240 because the
>> vendor that I purchased the cards from listed that 9240 as being
>> PCI-Express 2.0, but didn't say that about the 9211.  I also got the
>> impression that the 9240 recognized JBOD drives with the off-the-shelf
>> firmware, whereas the 9211 did not.
>>
>> Even LSI's own site is a bit confusing.  They list the 9211 in the HBA
>> section, but its specs don't mention JBOD, whereas the 9240 is listed in
>> the RAID section and its specs do list JBOD.  If the only physical
>> difference between the cards is the connector position, it seems odd
>> that they don't offer products with all the combinations of firmware and
>> connector position.
>>
>> I haven't configured the ZFS pool yet, but I didn't have any trouble
>> installing FreeBSD 9.1-BETA on the GPT partitioned boot drive, which
>> shows up as an mfi device.  I'm planning on getting the ZFS pool up and
>> running in the next few days.
> 
> HBA's are the way to go if your using ZFS to manage the disks, you only
> need RAID if your using a FS which doesn't manage the disk side well
> such as UFS.
> 
> Its often quite common for RAID controllers to actually be slower
> vs RAID controllers as the RAID stack can get in the way.
> 
> JBOD is generally what HBA's do by default which may be the reason
> why LSI's site doesn't mention it.
> 
>    Regards
>    Steve

Just to clear up,

The 9240 is a sas2008 based card with the megaraid software on top of
it.  In it's default config from LSI the FreeBSD mfi will recognize it
in later versions of FreeBSD (The upcoming 9.1  for sure)  Older
versions of mfi will not recognize it.

The card can be flashed with IT firmware and then becomes a 9211 HBA,
but it's a bit more expensive than a 9211 is so that doesn't make sense
to do in many cases.

On the dmesg posted the firmware on the card is phase 11.  This *must*
be in lockstep with the driver version or the card may not play nicely.
 FreeBSD 8.3 and 9.0 have v13 of the driver, the upcoming 9.1 will have
v14.  Note that v14 fixes a *ton* of stability bugs, including issues
where bad drives would hang the controller or prevent systems from booting.

Thanks,

Josh Paetzel