database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-02 09:02:37 +03:00
Code Activity

Fix comments on wal_level=minimal, CREATE TABLESPACE and CREATE DATABASE.

Browse Source 
Commit 97ddda8a82 removed the rmtree()
behavior from XLOG_TBLSPC_CREATE, obsoleting that part of the comment.
The comment's point about XLOG_DBASE_CREATE was wrong when commit
fa0f466d53 introduced the point.  (It
would have been accurate if that commit had predated commit
fbcbc5d06f introducing the second
checkpoint of CREATE DATABASE.)  Nothing can skip log_smgrcreate() on
the basis of wal_level=minimal, so don't comment on that.

Commit c6b92041d3 expanded WAL skipping
from five specific operations to relfilenodes generally, hence the
CreateDatabaseUsingFileCopy() comment change.

Discussion: https://postgr.es/m/20231008022204.cc@rfd.leadboat.com
This commit is contained in:
Noah Misch
2024-08-18 12:03:59 -07:00
parent 03e9b958ee
commit 64740853f0
2 changed files with 5 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
src/backend/access/heap/heapam_handler.c
View File

@ -605,9 +605,7 @@ heapam_relation_set_new_filelocator(Relation rel,
/* /*
* If required, set up an init fork for an unlogged table so that it can * If required, set up an init fork for an unlogged table so that it can
* be correctly reinitialized on restart. Recovery may remove it while * be correctly reinitialized on restart.
* replaying, for example, an XLOG_DBASE_CREATE* or XLOG_TBLSPC_CREATE
* record. Therefore, logging is necessary even if wal_level=minimal.
*/ */
if (persistence == RELPERSISTENCE_UNLOGGED) if (persistence == RELPERSISTENCE_UNLOGGED)
{ {

7
src/backend/commands/dbcommands.c
View File

@ -644,9 +644,10 @@ CreateDatabaseUsingFileCopy(Oid src_dboid, Oid dst_dboid, Oid src_tsid,
* make the XLOG entry for the benefit of PITR operations). This avoids * make the XLOG entry for the benefit of PITR operations). This avoids
* two nasty scenarios: * two nasty scenarios:
* *
* #1: When PITR is off, we don't XLOG the contents of newly created * #1: At wal_level=minimal, we don't XLOG the contents of newly created
* indexes; therefore the drop-and-recreate-whole-directory behavior of * relfilenodes; therefore the drop-and-recreate-whole-directory behavior
* DBASE_CREATE replay would lose such indexes. * of DBASE_CREATE replay would lose such files created in the new
* database between our commit and the next checkpoint.
* *
* #2: Since we have to recopy the source database during DBASE_CREATE * #2: Since we have to recopy the source database during DBASE_CREATE
* replay, we run the risk of copying changes in it that were committed * replay, we run the risk of copying changes in it that were committed