Re: Parallel Apply
Álvaro Herrera <alvherre@kurilemu.de>
From: Álvaro Herrera <alvherre@kurilemu.de>
To: "Zhijie Hou (Fujitsu)" <houzj.fnst@fujitsu.com>
Cc: "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>, 'Amit Kapila' <amit.kapila16@gmail.com>, Tomas Vondra <tomas@vondra.me>, Dilip Kumar <dilipbalaut@gmail.com>, Andrei Lepikhov <lepihov@gmail.com>, wenhui qiu <qiuwenhuifx@gmail.com>,
PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2026-04-17T05:48:12Z
Lists: pgsql-hackers
Hello, I have a quick question about this work -- is there an expectation of how quicker parallel apply is, compared to our normal (serial) apply, for average cases? Are we talking 20% faster, 2x faster, 10x faster? (When I say average, I mean not considering fringe cases where the workload is such that very little paralelization can be done, and also those where you have a contrived case with one thousand parallel processes each making progress separately to the point where you get ridiculously high numbers. I mean something that can occur in realistic workloads.) My point is that if it's 20% faster, it's nice. But if it's, say, 4x faster, then it's probably groundbreaking to the point that it may enable new use cases not currently possible. Thoughts, pointers? Many thanks -- Álvaro Herrera Breisgau, Deutschland — https://www.EnterpriseDB.com/ "¿Qué importan los años? Lo que realmente importa es comprobar que a fin de cuentas la mejor edad de la vida es estar vivo" (Mafalda)