Re: Parallel Seq Scan vs kernel read ahead - Mailing list pgsql-hackers

From Thomas Munro
Subject Re: Parallel Seq Scan vs kernel read ahead
Date
Msg-id CA+hUKGKnBHSN5towU+k8pQJnM8cWUwYKnG8BzpPRQAnWunp5yQ@mail.gmail.com
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In response to Re: Parallel Seq Scan vs kernel read ahead  (Ranier Vilela <ranier.vf@gmail.com>)
Responses Re: Parallel Seq Scan vs kernel read ahead  (Ranier Vilela <ranier.vf@gmail.com>)
List pgsql-hackers
On Thu, May 21, 2020 at 11:51 AM Ranier Vilela <ranier.vf@gmail.com> wrote:
> Em qua., 20 de mai. de 2020 às 20:48, Thomas Munro <thomas.munro@gmail.com> escreveu:
>> On Thu, May 21, 2020 at 11:15 AM Ranier Vilela <ranier.vf@gmail.com> wrote:
>> > postgres=# set max_parallel_workers_per_gather = 0;
>> > Time: 227238,445 ms (03:47,238)
>> > postgres=# set max_parallel_workers_per_gather = 1;
>> > Time: 138027,351 ms (02:18,027)
>>
>> Ok, so it looks like NT/NTFS isn't suffering from this problem.
>> Thanks for testing!
>
> Maybe it wasn’t clear, the tests were done with your patch applied.

Oh!  And how do the times look without it?



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