Re: [PATCH] Speed up repeat() for larger counts

From: ChenhuiMo <chenhuimo(dot)mch(at)qq(dot)com>
To: Jan Nidzwetzki <jan(at)planetscale(dot)com>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org>
Cc: Jeevan Chalke <jeevan(dot)chalke(at)enterprisedb(dot)com>, Heikki Linnakangas <hlinnaka(at)iki(dot)fi>
Subject: Re: [PATCH] Speed up repeat() for larger counts
Date: 2026-09-15 08:06:31
Message-ID: tencent_CB6CCF9832ACA15562A4B67CAF3E0F528C0A@qq.com
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Hi Jan,

Thanks for the review.

I have updated the patch set based on your comments:

- removed CHECK_FOR_INTERRUPTS() after memset()
- added a short comment for the single-byte fast path
- added regression tests for the early-return cases and the memset() path
- versioned the patch series as v2

I also confirmed that the author information in the patches is the name
and email address I want to use.

The updated v2 patch set is attached.

Thanks,
Chenhui

Attachment Content-Type Size
v2-0001-Return-early-from-repeat-for-empty-results.patch application/octet-stream 1.9 KB
v2-0002-Use-memset-in-repeat-for-single-byte-strings.patch application/octet-stream 1.9 KB

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