database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-06-29 10:41:53 +03:00
Code Activity

Remove lazy_scan_heap parallel VACUUM comment block.

Browse Source 
This doesn't belong next to very high level discussion of the tasks that
lazy_scan_heap performs.  There is already a similar, longer comment
block at the top of vacuumlazy.c that mentions lazy_scan_heap directly.
This commit is contained in:
Peter Geoghegan
2021-11-21 16:22:57 -08:00
parent 282b6d00ab
commit 97f5aef609
1 changed files with 0 additions and 12 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
src/backend/access/heap/vacuumlazy.c
View File

@ -886,18 +886,6 @@ heap_vacuum_rel(Relation rel, VacuumParams *params,
* for dead-tuple TIDs, invoke lazy_vacuum to vacuum indexes and vacuum * for dead-tuple TIDs, invoke lazy_vacuum to vacuum indexes and vacuum
* heap relation during its own second pass over the heap. * heap relation during its own second pass over the heap.
* *
* If the table has at least two indexes, we execute both index vacuum
* and index cleanup with parallel workers unless parallel vacuum is
* disabled. In a parallel vacuum, we enter parallel mode and then
* create both the parallel context and the DSM segment before starting
* heap scan so that we can record dead tuples to the DSM segment. All
* parallel workers are launched at beginning of index vacuuming and
* index cleanup and they exit once done with all indexes. At the end of
* this function we exit from parallel mode. Index bulk-deletion results
* are stored in the DSM segment and we update index statistics for all
* the indexes after exiting from parallel mode since writes are not
* allowed during parallel mode.
*
* If there are no indexes then we can reclaim line pointers on the fly; * If there are no indexes then we can reclaim line pointers on the fly;
* dead line pointers need only be retained until all index pointers that * dead line pointers need only be retained until all index pointers that
* reference them have been killed. * reference them have been killed.