digoal
2022-08-19
PostgreSQL , smgrextend , create database , saas
saas场景可能一个客户一个database, database基于模板库, 一个实例里面可能有很多database. 创建database可能也是比较频繁的操作.
例如sap, odoo, ToB类的云端软件服务(钉钉、云协同等).
标准动作： 模板统一, 新增客户时, 使用模板创建数据库.
PostgreSQL 15 preview - create database wal-logged 时支持批量扩展数据块, 提升基于模板创建数据库性能, SaaS场景
When using the WAL-logged CREATE DATABASE strategy, bulk extend.
author Robert Haas <rhaas@postgresql.org>
Thu, 18 Aug 2022 15:09:39 +0000 (11:09 -0400)
committer Robert Haas <rhaas@postgresql.org>
Thu, 18 Aug 2022 15:26:34 +0000 (11:26 -0400)
commit 3e63e8462f31657c8ae1c541c92daf43ede8f038
tree 22b363ee3d8343b88a9cd8a167be0b1ea61eb551 tree
parent 27f1774aac1f8ffe642b55e78dbe0b64ed082cc6 commit | diff
When using the WAL-logged CREATE DATABASE strategy, bulk extend.
This should improve performance, and was suggested by Andres Freund.
Back-patch to v15 to keep the code consistent across branches.
Dilip Kumar
Discussion: http://postgr.es/m/C3458199-FEDD-4356-865A-08DFAA5D4065@anarazel.de
Discussion: http://postgr.es/m/CAFiTN-sJ0vVpJrZ=R5M+g7Tr8=NN4wKOtrqOcDEsfFfnZgivVA@mail.gmail.com
+ /*
+ * Bulk extend the destination relation of the same size as the source
+ * relation before starting to copy block by block.
+ */
+ memset(buf.data, 0, BLCKSZ);
+ smgrextend(smgropen(dstlocator, InvalidBackendId), forkNum, nblocks - 1,
+ buf.data, true);
+
