Re: [HACKERS] pgbench: faster version of tpcb-like transaction - Mailing list pgsql-hackers

From Peter Geoghegan
Subject Re: [HACKERS] pgbench: faster version of tpcb-like transaction
Date
Msg-id CAH2-WznfoMwj6TLdfy1sXkAsbmqPWVtOBZrx47hJvYzcG3boBA@mail.gmail.com
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In response to Re: [HACKERS] pgbench: faster version of tpcb-like transaction  (Jeff Janes <jeff.janes@gmail.com>)
List pgsql-hackers
On Sat, Aug 26, 2017 at 4:59 PM, Jeff Janes <jeff.janes@gmail.com> wrote:
> I still get a 2 fold improvement, from 13668 to 27036, when both
> transactions are tested with -M prepared.
>
> I am surprised, I usually haven't seen that much difference for the default
> queries between prepared or not, to the point that I got out of the habit of
> testing with it.  But back when I was testing with and without
> systematically, I did notice that it changed a lot depending on hardware and
> concurrency.  And of course from version to version different bottlenecks
> come and go.

I must admit that I had a similar unpleasant surprise at one point --
"-M prepared" seems to matter *a lot* these days. That's the default
that I'd change, if any.

-- 
Peter Geoghegan



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