Re: Choosing parallel_degree

On 12 April 2016 at 14:11, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
> On 12 April 2016 at 13:53, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>>
>> On Mon, Apr 11, 2016 at 5:45 PM, Simon Riggs <simon(at)2ndquadrant(dot)com>
>> wrote:
>> > On 8 April 2016 at 17:49, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> >> With the patch, you can - if you wish - substitute
>> >> some other number for the one the planner comes up with.
>> >
>> > I saw you're using AccessExclusiveLock, the reason being it affects
>> > SELECTs.
>> >
>> > That is supposed to apply when things might change the answer from a
>> > SELECT,
>> > whereas this affects only the default for a plan.
>> >
>> > Can I change this to a lower setting? I would have done this before
>> > applying
>> > the patch, but you beat me to it.
>>
>> I don't have a problem with reducing the lock level there, if we're
>> convinced that it's safe.
>
>
> I'll run up a patch, with appropriate comments.

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