Re: WIP patch for hint bit i/o mitigation

On 12/14/2012 09:57 PM, Amit Kapila wrote:
>>
>> I need to validate the vacuum results. It's possible that this is
>> solvable by tweaking xmin check inside vacuum. Assuming that's fixed,
>> the question stands: do the results justify the change?  I'd argue
>> 'maybe' 
> We can try with change (assuming change is small) and see if the performance
> gain is good, then discuss whether it really justifies.
> I think the main reason for Vacuum performance hit is that in the test pages
> are getting dirty only due to setting of hint bit
> by Vacuum. 
>
>> -- I'd like to see the bulk insert performance hit reduced if
>> possible.
> I think if we can improve performance for bulk-insert case, then this patch
> has much more value. 
Has there been any movement in this - more benchmarks and data showing
that it really does improve performance, or that it really isn't helpful?

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