Re: pgsql: Add kqueue(2) support to the WaitEventSet API.

On Mon, Feb 24, 2020 at 12:24 PM Tom Lane  wrote:
> On reflection, trying to make ReserveExternalFD serve two different
> use-cases was pretty messy.  Here's a version that splits it into two
> functions.  I also took the trouble to fix dblink.

+    /*
+     * We don't want more than max_safe_fds / 3 FDs to be consumed for
+     * "external" FDs.
+     */
+    if (numExternalFDs < max_safe_fds / 3)

This looks pretty reasonable to me.

I'll have a new patch set to create a common WES at startup over on
that other thread in a day or two.