Re: Raid 5 vs Raid 10 Benchmarks Using bonnie++

On Aug 17, 2011, at 1:35 PM, ktm(at)rice(dot)edu wrote:

> On Wed, Aug 17, 2011 at 01:32:41PM -0500, Ogden wrote:
>>
>> On Aug 17, 2011, at 1:31 PM, ktm(at)rice(dot)edu wrote:
>>
>>> On Wed, Aug 17, 2011 at 01:26:56PM -0500, Ogden wrote:
>>>> I am using bonnie++ to benchmark our current Postgres system (on RAID 5) with the new one we have, which I have configured with RAID 10. The drives are the same (SAS 15K). I tried the new system with ext3 and then XFS but the results seem really outrageous as compared to the current system, or am I reading things wrong?
>>>>
>>>> The benchmark results are here:
>>>>
>>>> http://malekkoheavyindustry.com/benchmark.html
>>>>
>>>>
>>>> Thank you
>>>>
>>>> Ogden
>>>
>>> That looks pretty normal to me.
>>>
>>> Ken
>>
>> But such a jump from the current db01 system to this? Over 20 times difference from the current system to the new one with XFS. Is that much of a jump normal?
>>
>> Ogden
>
> Yes, RAID5 is bad for in many ways. XFS is much better than EXT3. You would get similar
> results with EXT4 as well, I suspect, although you did not test that.

i tested ext4 and the results did not seem to be that close to XFS. Especially when looking at the Block K/sec for the Sequential Output.

http://malekkoheavyindustry.com/benchmark.html

So XFS would be best in this case?

Thank you

Ogden