From: Tom Lane <tgl@sss.pgh.pa.us>
To: Amit Khandekar <amitdkhan.pg@gmail.com>
cc: Robert Haas <robertmhaas@gmail.com>,
        Tomas Vondra <tomas.vondra@2ndquadrant.com>,
        Alvaro Herrera from 2ndQuadrant <alvherre@alvh.no-ip.org>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: logical decoding : exceeded maxAllocatedDescs for .spill files
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Comments: In-reply-to Amit Khandekar <amitdkhan.pg@gmail.com>
	message dated "Fri, 13 Sep 2019 21:28:12 +0530"
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Date: Fri, 13 Sep 2019 12:14:32 -0400
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Amit Khandekar <amitdkhan.pg@gmail.com> writes:
> You mean tracking excess kernel fds right ? Yeah, we can use VFDs so
> that excess fds are automatically closed. But Alvaro seems to be
> talking in context of tracking of file seek position. VFD  does not
> have a mechanism to track file offsets if one of the vfd cached file
> is closed and reopened.

Hm.  It used to, but somebody got rid of that on the theory that
we could use pread/pwrite instead.  I'm inclined to think that that
was the right tradeoff, but it'd mean that getting logical decoding
to adhere to the VFD API requires extra work to track file position
on the caller side.

Again, though, the advice that's been given here is that we should
fix logical decoding to use the VFD API as it stands, not change
that API.  I concur with that.

			regards, tom lane