Re: Shared Memory: How to use SYSV rather than MMAP ?

Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> On Wed, Dec 26, 2018 at 11:43 AM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>> I'm -1 on making this user configurable via a GUC; that adds documentation
>> and compatibility burdens that we don't need, for something of no value
>> to 99.99% of users.
> ...
> You may be right that this is of no value to a high percentage our
> users, but I think that's only because a high percentage of our users
> run Linux or Windows, which happen not to be affected. I'm rather
> proud, though, of PostgreSQL's long history of trying to be
> cross-platform. Even if operating systems like AIX or BSD are a small
> percentage of the overall user base, I think it's totally fair to add
> a GUC which likely be helpful to a large percentage of those people,
> and I think the GUC proposed here likely falls into that category.

You misread what I said. I don't say that we shouldn't fix this;
what I'm saying is we should not do so via a user-configurable knob.
We should be able to auto-configure this and just handle it internally.
I have zero faith in the idea that users would set the knob correctly.

regards, tom lane