Re: file system and raid performance

Gregory S. Youngblood wrote:
>> From: Mark Kirkwood [mailto:markir@paradise.net.nz]
>> Mark Wong wrote:
>>
>>> On Mon, Aug 4, 2008 at 10:56 PM, Gregory S. Youngblood
>>>
>> <greg@tcscs.com> wrote:
>>
>>>> I recently ran some tests on Ubuntu Hardy Server (Linux) comparing
>>>>
>> JFS, XFS,
>>
>>>> and ZFS+FUSE. It was all 32-bit and on old hardware, plus I only
>>>>
>> used
>>
>>>> bonnie++, so the numbers are really only useful for my hardware.
>>>>
>>>> What parameters were used to create the XFS partition in these
>>>>
>> tests? And,
>>
>>>> what options were used to mount the file system? Was the kernel 32-
>>>>
>> bit or
>>
>>>> 64-bit? Given what I've seen with some of the XFS options (like
>>>>
>> lazy-count),
>>
>>>> I am wondering about the options used in these tests.
>>>>
>>>>
>>> The default (no arguments specified) parameters were used to create
>>> the XFS partitions.  Mount options specified are described in the
>>> table.  This was a 64-bit OS.
>>>
>>>
>> I think it is a good idea to match the raid stripe size and give some
>> indication of how many disks are in the array. E.g:
>>
>> For a 4 disk system with 256K stripe size I used:
>>
>>  $ mkfs.xfs -d su=256k,sw=2 /dev/mdx
>>
>> which performed about 2-3 times quicker than the default (I did try
>> sw=4
>> as well, but didn't notice any difference compared to sw=4).
>>
>
> [Greg says]
> I thought that xfs picked up those details when using md and a soft-raid
> configuration.
>
>
>
>
>
>
You are right, it does (I may be recalling performance from my other
machine that has a 3Ware card - this was a couple of years ago...)
Anyway, I'm thinking for the Hardware raid tests they may need to be
specified.

Cheers

Mark