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

Robert Haas wrote:
> On Tue, Mar 21, 2017 at 10:01 AM, Amit Kapila <amit.kapila16@gmail.com> wrote:

> > Sure, we can try that.  I think we need to try it with
> > synchronous_commit = off, otherwise, WAL writes completely overshadows
> > everything.
> 
> synchronous_commit = off is a much more realistic scenario than fsync = off.

Sure, synchronous_commit=off is a reasonable case.  But I say if we lose
a few % on the case where you update only the first indexed of a large
number of very wide columns all indexed, and this is only noticeable if
you don't write WAL and only if you update all the rows in the table,
then I don't see much reason for concern.

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