On Thu, Jul 2, 2015 at 1:47 AM, Gavin Flower <
GavinFlower@archidevsys.co.nz> wrote:
>
> On 01/07/15 17:37, Amit Kapila wrote:
>>
>> Yes, you are right and we have done quite some testing (on the hardware
>> available) with this patch (with different approaches) to see how much
>> difference it creates for IO and CPU, with respect to IO we have found
>> that it doesn't help much [1], though it helps when the data is cached
>> and there are really good benefits in terms of CPU [2].
>>
> [...]
>
> I assume your answer refers to a table on one spindle of spinning rust.
>
>
> QUESTIONS:
>
> 1. what about I/O using an SSD?
>
> 2. what if the table is in a RAID array (of various types), would
> having the table spread over multiple spindles help?
>
I think it will be helpful if we could get the numbers on more type of m/c's,
please feel free to test and share the data if you have access to such
m/c's.
Attached, find the rebased version of patch.
Note - You need to first apply the assess-parallel-safety patch which you
can find at: