Date: Wed, 10 Jul 2024 13:59:15 -0500
From: Nathan Bossart <nathandbossart@gmail.com>
To: Antonin Houska <ah@cybertec.at>
Cc: pgsql-hackers@lists.postgresql.org
Subject: Re: Missed opportunity for bsearch() in
 TransactionIdIsCurrentTransactionId()?
Message-ID: <Zo7aA2m35vGR56MN@nathan>
References: <36977.1720623613@antos>
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On Wed, Jul 10, 2024 at 05:00:13PM +0200, Antonin Houska wrote:
> I don't quite understand why TransactionIdIsCurrentTransactionId() implements
> binary search in ParallelCurrentXids "from scratch" instead of using
> bsearch().

I believe there are a number of open-coded binary searches in the tree.  My
concern with switching them to bsearch() would be the performance impact of
using a function pointer for the comparisons.  Perhaps we could add a
couple of inlined binary search implementations for common types to replace
many of the open-coded ones.

-- 
nathan