Re: Re: index and data tablespaces on two separate drives or one RAID 0?

On 07/06/12 5:51 PM, ach wrote:
>> My fastest postgresql servers have everything on one raid10, using 16 or
>> >20 15000 rpm SAS2 drives on a 1gb flash-backed cache controller.
> Thank you - that affirms what'd been my own growing supposition, and the
> plan
>
>> >why?
> Really?  ...Well, I mean, I'd just been going with what I'd seen asserted as
> the solid baseline position:  WAL should be on its own separate drive,
> devoid of any interference and/or interruption other than just writing WAL.
> To see that challenged is surprising; are you saying my interpretation on
> that point would be incorrect, and that assumption would be wrong?

putting everything on a single large raid10 ensures the IO is evenly
distributed across all spindles, given enough workload to keep that many
concurrent IOs active.



--
john r pierce                            N 37, W 122
santa cruz ca                         mid-left coast