Re: Testing Sandforce SSD - Mailing list pgsql-performance

From Yeb Havinga
Subject Re: Testing Sandforce SSD
Date
Msg-id 4C56DD8B.6050303@gmail.com
Whole thread Raw
In response to Re: Testing Sandforce SSD  (Merlin Moncure <mmoncure@gmail.com>)
Responses Re: Testing Sandforce SSD
List pgsql-performance
Merlin Moncure wrote:
> On Fri, Jul 30, 2010 at 11:01 AM, Yeb Havinga <yebhavinga@gmail.com> wrote:
>
>> Postgres settings:
>> 8.4.4
>> --with-blocksize=4
>> I saw about 10% increase in performance compared to 8KB blocksizes.
>>
>
> That's very interesting -- we need more testing in that department...
>
Definately - that 10% number was on the old-first hardware (the core 2
E6600). After reading my post and the 185MBps with 18500 reads/s number
I was a bit suspicious whether I did the tests on the new hardware with
4K, because 185MBps / 18500 reads/s is ~10KB / read, so I thought thats
a lot closer to 8KB than 4KB. I checked with show block_size and it was
4K. Then I redid the tests on the new server with the default 8KB
blocksize and got about 4700 tps (TPC-B/300)... 67/47 = 1.47. So it
seems that on newer hardware, the difference is larger than 10%.

regards,
Yeb Havinga


pgsql-performance by date:

Previous
From: Merlin Moncure
Date:
Subject: Re: Testing Sandforce SSD
Next
From: Mark Rostron
Date:
Subject: Re: what does "initplan" operation in explain output mean?