Re: [HACKERS] rewrite HeapSatisfiesHOTAndKey

Pavan Deolasee wrote:

> A transaction then updates the second column in the table. So the
> refactored patch will do heap_getattr() on more columns that the master
> while checking if HOT update is possible and before giving up.

Thanks.

> 1-client
>               Master                     Refactored
> Run1 8774.089935 8979.068604
> Run2 8509.2661 8943.613575
> Run3 8879.484019 8950.994425
> 
> 
> 8-clients
>               Master                     Refactored
> Run1 22520.422448 22672.798871
> Run2 21967.812303 22022.969747
> Run3 22305.073223 21909.945623

Wow, this is very surprising.  I was expecting a slight performance
decrease, not this.  I will try to reproduce these numbers.

One thing worth mentioning is that the current implementation is not
very good -- I just kept the attribute check loop as it was in the
original, which uses heap_getattr.  If we used incremental extraction
such as what we do in slot_getattr, it could be made a bit faster too.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services