Re: WIP patch for hint bit i/o mitigation

On Fri, Jan 18, 2013 at 8:57 AM, Atri Sharma <atri.jiit@gmail.com> wrote:
>
> Hello all,
>
> Sorry for the delay in updating the hackers list with the current status.
>
> I recently did some profiling using perf on PostgreSQL 9.2 with and without our patch.
>
> I noticed that maximum time is being spent on heapgettup function. Further investigation and a bit of a hunch leads
meto believe that we may be adversely affecting the visibility map optimisation that directly interact with the
visibilityfunctions, that our patch straight away affects. 
>
> If this is the case, we may really need to get down to the design of our patch, and maybe see which visibility
function/functionswe are affecting, and see if we can mitigate the affect. 
>
> Please let me know your inputs on this.

Any scenario that involves non-trivial amount of investigation or
development should result in us pulling the patch for rework and
resubmission in later 'fest....it's closing time as they say :-).

merlin