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

From David Rowley
Subject Re: Parallel Seq Scan vs kernel read ahead
Date
Msg-id CAApHDvp8DYsi+oD1R_WVjhqZRVSRufsUwgSKVyD1HhHHfj5kAQ@mail.gmail.com
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In response to Re: Parallel Seq Scan vs kernel read ahead  (David Rowley <dgrowleyml@gmail.com>)
Responses Re: Parallel Seq Scan vs kernel read ahead
List pgsql-hackers
On Thu, 21 May 2020 at 17:06, David Rowley <dgrowleyml@gmail.com> wrote:
> For the patch. I know you just put it together quickly, but I don't
> think you can do that ramp up the way you have. It looks like there's
> a risk of torn reads and torn writes and I'm unsure how much that
> could affect the test results here.

Oops. On closer inspection, I see that memory is per worker, not
global to the scan.



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