Re: Parallel query and temp_file_limit

On Tue, Jul 5, 2016 at 1:58 PM, Peter Geoghegan <pg(at)heroku(dot)com> wrote:
> On Tue, Jul 5, 2016 at 7:45 AM, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
>> Since Peter doesn't seem in a hurry to produce a patch for this issue,
>> I wrote one. It is attached. I'll commit this in a day or two if
>> nobody objects.
>
> Sorry about the delay.
>
> Your patch seems reasonable, but I thought we'd also want to change
> "per session" to "per session (with an additional temp_file_limit
> allowance within each parallel worker)" for temp_file_limit.
>
> I think it's worthwhile noting this for temp_file_limit specifically,
> since it's explicitly a per session limit, whereas users are quite
> used to the idea that work_mem might be doled out multiple times for
> multiple executor nodes.

I think that it is not worth mentioning specifically for
temp_file_limit; to me that seems to be a hole with no bottom. We'll
end up arguing about which GUCs should mention it specifically and
there will be no end to it.

We can see what other people think, but that's my position.

--
Robert Haas
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