Re: Excessive PostmasterIsAlive calls slow down WAL redo

Andres Freund wrote:
> 
> On April 9, 2018 6:31:07 PM PDT, Alvaro Herrera <alvherre@alvh.no-ip.org> wrote:

> >Would it work to use this second pipe, to which each child writes a
> >byte that postmaster never reads, and then rely on SIGPIPE when
> >postmaster dies?  Then we never need to do a syscall.
> 
> I'm not following, could you expand on what you're suggesting?  Note
> that you do not get SIGPIPE for already buffered writes.  Which
> syscall can we avoid?

Ah.  I was thinking we'd get SIGPIPE from the byte sent at the start, as
soon as the kernel saw that postmaster abandoned the fd by dying.
Scratch that then.

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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