Excerpts from Tom Lane's message of jue jun 02 15:49:53 -0400 2011:
> The results of such a test wouldn't be worth the electrons they're
> written on anyway: you're ignoring the likelihood that two instances of
> shared memory would overrun the kernel's SHMALL limit, when a single
> instance would be fine.
Well, overrunning SHMALL sets a different errno than overrunning SHMMAX,
so at least it's possible to notice the problem.
> Given that you can't do it in the context of a live installation, just
> trying to start the postmaster and seeing if it works (same as initdb
> does) seems as good as anything else.
That's precisely what this is trying to avoid.
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Álvaro Herrera <alvherre@commandprompt.com>
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