From f892150076dbee167ecd850d3628443d0fb34d82 Mon Sep 17 00:00:00 2001 From: David Rowley Date: Fri, 21 Oct 2022 09:30:27 +1300 Subject: [PATCH] Doc: fix outdated wording about parallel seq scans 56788d215 adjusted the parallel seq scan code so that instead of handing out a single block at a time to parallel workers, it now hands out ranges of blocks. Here we update the documentation which still claimed that workers received just 1 block at a time. Reported-by: Zhang Mingli Discussion: https://postgr.es/m/17c99615-2c3b-4e4e-9d0b-424a66a7bccd@Spark Backpatch-through: 14, where 56788d215 was added. --- doc/src/sgml/parallel.sgml | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/doc/src/sgml/parallel.sgml b/doc/src/sgml/parallel.sgml index 13479d7e5e..3e8326d46c 100644 --- a/doc/src/sgml/parallel.sgml +++ b/doc/src/sgml/parallel.sgml @@ -272,8 +272,9 @@ EXPLAIN SELECT * FROM pgbench_accounts WHERE filler LIKE '%x%'; In a parallel sequential scan, the table's blocks will - be divided among the cooperating processes. Blocks are handed out one - at a time, so that access to the table remains sequential. + be divided into ranges and shared among the cooperating processes. Each + worker process will complete the scanning of its given range of blocks before + requesting an additional range of blocks.