Subject: Re: Rename max_parallel_degree?
To: Amit Kapila <amit.kapila16@gmail.com>
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Cc: Robert Haas <robertmhaas@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>,
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From: Julien Rouhaud <julien.rouhaud@dalibo.com>
Message-ID: <fab6510f-a303-4144-06c3-e2e63ca50d30@dalibo.com>
Date: Wed, 29 Jun 2016 16:00:57 +0200
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On 29/06/2016 08:51, Amit Kapila wrote:
> On Wed, Jun 29, 2016 at 11:54 AM, Julien Rouhaud
> <julien.rouhaud@dalibo.com> wrote:
>> Or should we allow setting it to -1 for instance to disable the limit?
>>
> 
> By disabling the limit, do you mean to say that only
> max_parallel_workers_per_gather will determine the workers required or
> something else?

I meant what the current behavior (before this patch) is, which is
probably what some user without custom dynamic bgworker may like to
have.  Otherwise, you'd have to change two parameters to effectively
increase parallelism, and I think it can also cause some confusion.

>  If earlier, then I am not sure if it is good idea,
> because it can cause some confusion to the user about usage of both
> the parameters together.
> 

I also agree.  I don't see an ideal solution, so just keeping this patch
behavior is fine for me.

-- 
Julien Rouhaud
http://dalibo.com - http://dalibo.org


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