Re: effective_io_concurrency's steampunk spindle maths - Mailing list pgsql-hackers

From Thomas Munro
Subject Re: effective_io_concurrency's steampunk spindle maths
Date
Msg-id CA+hUKG+6Cm9wr0=cLkCA__8uxcLfNxrhc=52BUVescVtm2MiHg@mail.gmail.com
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In response to Re: effective_io_concurrency's steampunk spindle maths  (Tomas Vondra <tomas.vondra@2ndquadrant.com>)
Responses Re: effective_io_concurrency's steampunk spindle maths  (Evgeniy Shishkin <itparanoia@gmail.com>)
List pgsql-hackers
On Sat, Mar 7, 2020 at 8:35 AM Tomas Vondra
<tomas.vondra@2ndquadrant.com> wrote:
> I think the main issue with keeping the current GUC name is that if you
> had a value that worked, we'll silently interpret it differently. Which
> is a bit annoying :-(

Yeah.  Perhaps we should just give the formula for translating v12
settings to v13 settings in the release notes.  If we don't rename the
GUC, you won't be forced to contemplate this when you upgrade, so the
amount of prefetching we do will go down a bit given the same value.
That is indeed what led me to start thinking about what a good new
name would be.  Now that I've been talked out of the "random_page"
part, your names look like sensible candidates, but I wonder if there
is some way to capture that it's "per operation"...



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