Re: Patch: Write Amplification Reduction Method (WARM)

Pavan Deolasee wrote:
> On Wed, Mar 29, 2017 at 3:42 AM, Alvaro Herrera <alvherre@2ndquadrant.com>
> wrote:
> 
> > I pushed 0002 after some makeup, since it's just cosmetic and not
> > controversial.
> 
> Thanks. I think your patch of tracking interesting attributes seems ok too
> after the performance issue was addressed. Even though we can still improve
> that further, at least Mithun confirmed that there is no significant
> regression anymore and in fact for one artificial case, patch does better
> than even master.

Great, thanks.  I pushed it, too.  One optimization we could try is
using slot deform instead of repeated heap_getattr().  Patch is
attached.  I haven't benchmarked it.

On top of that, but perhaps getting in the realm of excessive
complication, we could see if the bitmapset is a singleton, and if it is
then do heap_getattr without creating the slot.  That'd require to have
a second copy of heap_tuple_attr_equals() that takes a HeapTuple instead
of a TupleTableSlot.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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