From: Tom Lane <tgl@sss.pgh.pa.us>
To: Xiaoran Wang <fanfuxiaoran@gmail.com>
cc: pgsql-hackers@lists.postgresql.org, Andres Freund <andres@anarazel.de>
Subject: Re: Recovering from detoast-related catcache invalidations
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Comments: In-reply-to Xiaoran Wang <fanfuxiaoran@gmail.com>
	message dated "Sat, 13 Jan 2024 17:02:15 +0800"
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Xiaoran Wang <fanfuxiaoran@gmail.com> writes:
> Hmm, how about first checking if any invalidated shared messages have been
> accepted, then rechecking the tuple's visibility?
> If there is no invalidated shared message accepted during
> 'toast_flatten_tuple',
> there is no need to do then visibility check, then it can save several
> CPU cycles.

Meh, I'd just as soon not add the additional dependency/risk of bugs.
This is an expensive and seldom-taken code path, so I don't think
shaving a few cycles is really important.

			regards, tom lane