Re: [HACKERS] Patch: Write Amplification Reduction Method (WARM)

Bruce Momjian wrote:
> On Thu, Feb 23, 2017 at 03:03:39PM -0300, Alvaro Herrera wrote:
> > Bruce Momjian wrote:
> > 
> > > As I remember, WARM only allows
> > > a single index-column change in the chain.  Why are you seeing such a
> > > large performance improvement?  I would have thought it would be that
> > > high if we allowed an unlimited number of index changes in the chain.
> > 
> > The second update in a chain creates another non-warm-updated tuple, so
> > the third update can be a warm update again, and so on.
> 
> Right, before this patch they would be two independent HOT chains.

No, they would be a regular update chain, not HOT updates.

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