Re: [COMMITTERS] pgsql: Add max_parallel_workers GUC. - Mailing list pgsql-hackers

From Tom Lane
Subject Re: [COMMITTERS] pgsql: Add max_parallel_workers GUC.
Date
Msg-id 20841.1480783382@sss.pgh.pa.us
Whole thread Raw
In response to Re: [COMMITTERS] pgsql: Add max_parallel_workers GUC.  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: [COMMITTERS] pgsql: Add max_parallel_workers GUC.  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes:
> On Dec 2, 2016, at 5:45 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Might work.  We've had very bad luck with GUC variables with
>> interdependent defaults, but maybe the user-visible knob could be a
>> percentage of max_connections or something like that.

> Seems like overkill. Let's just reduce the values a bit.

Agreed.  How about max_worker_processes = 8 as before, with
max_parallel_workers of maybe 6?  Or just set them both to 8.
I'm not sure that the out-of-the-box configuration needs to
leave backend slots locked down for non-parallel worker processes.
Any such process would require manual configuration anyway no?
        regards, tom lane



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