Hi everyone! I've also attached the pg_rewind optimization patch file for Postgres version 14.4. The previous patch file targets version Postgres version 15 Beta 1/2.
Thanks, Justin ________________________________ From: Justin Kwan <jk...@cloudflare.com> Sent: July 15, 2022 6:13 PM To: vignesh ravichandran <ad...@viggy28.dev> Cc: pgsql-hackers <pgsql-hack...@postgresql.org>; vignesh <vign...@cloudflare.com>; justinpk...@outlook.com <justinpk...@outlook.com> Subject: Re: Making pg_rewind faster Looping in my other email. On Thu, Jun 30, 2022 at 6:22 AM vignesh ravichandran <ad...@viggy28.dev<mailto:ad...@viggy28.dev>> wrote: Hi Hackers, I have been using pg_rewind in production for 2 years. One of the things that I noticed in pg_rewind is if it doesn't know what to do with a file "it copies". I understand it's the more safer option. After all, the alternative, pg_basebackup copies all the files from source to target. However, this is making pg_rewind inefficient when we have a high number of WAL files. Majority of the data (in most of my cases 95%+) that it copies are WAL files which are anyway same between the source and target. Skipping those same WAL files from copying will improve the speed of pg_rewind a lot. 1. Does pg_rewind need to copy WAL files before the WAL that contains the last common check point? Heikki's presentation https://pgsessions.com/assets/archives/pg_rewind-presentation-paris.pdf gave me a good overview and also explained the behavior what I mentioned. Thanks, Vignesh
v1-pg14.4-0001-Avoid-copying-WAL-segments-before-divergence-to-spee.patch
Description: v1-pg14.4-0001-Avoid-copying-WAL-segments-before-divergence-to-spee.patch
