Re: modeling parallel contention (was: Parallel Append implementation)

On 5 May 2017 at 13:37, Andres Freund <andres(at)anarazel(dot)de> wrote:
> On 2017-05-02 15:13:58 -0400, Robert Haas wrote:
>> Multiple people (including David Rowley
>> as well as folks here at EnterpriseDB) have demonstrated that for
>> certain queries, we can actually use a lot more workers and everything
>> works great. The problem is that for other queries, using a lot of
>> workers works terribly. The planner doesn't know how to figure out
>> which it'll be - and honestly, I don't either.
>
> Have those benchmarks, even in a very informal form, been shared /
> collected / referenced centrally? I'd be very interested to know where
> the different contention points are. Possibilities:

I posted mine on [1], although the post does not go into much detail
about the contention points. I only really briefly mention it at the
end.

[1] https://blog.2ndquadrant.com/parallel-monster-benchmark/#comment-248273

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David Rowley http://www.2ndQuadrant.com/
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