Re: XFS drops create/delete files to 6.6% of EXT3 (software raid) and to 0.6% of EXT3 (3ware hardware raid)

[Justin Piszcz <jpiszcz@lucidpixels.com>]

On Thu, 24 Apr 2008, Eric Sandeen wrote:

> Michael Darling wrote:
>> Eric, for the numbers you provided, are you using a single drive,
>> software raid, or hardware raid?  If a hardware raid, is it a 3ware card?
>
> it's a simple partition on a sata drive.
>
>> I hadn't seen the nobarrier mount option before.  Using that changes
>> sequential creates from about 190/second to about 2500/second, and
>> changes sequential deletes from about 170/second to about 3700/second.
>
> I wasn't recommending, necessarily, that you use it, but was just
> looking for bottlenecks...
>
>> I don't yet have a BBU for the 3ware card, but would certainly get one
>> if we go with the 3ware card before we start putting real data on the
>> raid.  Am I right that with a BBU unit and a battery backup for the
>> server as a whole, that nobarrier would be safe to use?
>>
>> Not using nobarrier, but using logbsize 256k changes sequential creates
>> from about 190/second to about 270/second.  So, it's an improvement, but
>> no where near where a software raid performs (1600/second) or where the
>> hardware raid performs with nobarrier.
>
> Default mkfs & mount w/ 256k logbufs:
>
> xfs,256k logbuf:	1353/s
>
>> On Thu, Apr 24, 2008 at 1:33 AM, David Chinner <dgc@sgi.com
>> <mailto:dgc@sgi.com>> wrote:
>>    > So I played with this a little on 2.6.25, on plain partitions.
>>    >
>>    > I saw similar numbers; for example, sequential creates:
>>    >
>>    > ext3:         23698/s
>>    > xfs:            319/s
>>    > xfs,nobarrier:         4478/s
>>
>>     And with logbsize=256k?
>>
>>     Cheers,
>>
>>     Dave.
>
>

Which program is this that you are using to measure this, bonnie++, or?