database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-10-21 02:52:47 +03:00
Code Activity

Replace explicit PIN entries in pg_depend with an OID range test.

Browse Source 
As of v14, pg_depend contains almost 7000 "pin" entries recording
the OIDs of built-in objects.  This is a fair amount of bloat for
every database, and it adds time to pg_depend lookups as well as
initdb.  We can get rid of all of those entries in favor of an OID
range check, i.e. "OIDs below FirstUnpinnedObjectId are pinned".

(template1 and the public schema are exceptions.  Those exceptions
are now wired into IsPinnedObject() instead of initdb's code for
filling pg_depend, but it's the same amount of cruft either way.)

The contents of pg_shdepend are modified likewise.

Discussion: https://postgr.es/m/3737988.1618451008@sss.pgh.pa.us
This commit is contained in:
Tom Lane
2021-07-15 11:41:47 -04:00
parent e529b2dc37
commit a49d081235
25 changed files with 290 additions and 432 deletions
Download Patch File Download Diff File Expand all files Collapse all files

16
src/include/access/transam.h
View File

@@ -165,10 +165,14 @@ FullTransactionIdAdvance(FullTransactionId *dest)
* when the .dat files in src/include/catalog/ do not specify an OID
* for a catalog entry that requires one. Note that genbki.pl assigns
* these OIDs independently in each catalog, so they're not guaranteed
* to be globally unique.
* to be globally unique. Furthermore, the bootstrap backend and
* initdb's post-bootstrap processing can also assign OIDs in this range.
* The normal OID-generation logic takes care of any OID conflicts that
* might arise from that.
*
* OIDS 12000-16383 are reserved for assignment during initdb
* using the OID generator. (We start the generator at 12000.)
* OIDs 12000-16383 are reserved for unpinned objects created by initdb's
* post-bootstrap processing. initdb forces the OID generator up to
* 12000 as soon as it's made the pinned objects it's responsible for.
*
* OIDs beginning at 16384 are assigned from the OID generator
* during normal multiuser operation. (We force the generator up to
@@ -184,11 +188,12 @@ FullTransactionIdAdvance(FullTransactionId *dest)
*
* NOTE: if the OID generator wraps around, we skip over OIDs 0-16383
* and resume with 16384. This minimizes the odds of OID conflict, by not
* reassigning OIDs that might have been assigned during initdb.
* reassigning OIDs that might have been assigned during initdb. Critically,
* it also ensures that no user-created object will be considered pinned.
* ----------
*/
#define FirstGenbkiObjectId 10000
#define FirstBootstrapObjectId 12000
#define FirstUnpinnedObjectId 12000
#define FirstNormalObjectId 16384
/*
@@ -289,6 +294,7 @@ extern void SetTransactionIdLimit(TransactionId oldest_datfrozenxid,
extern void AdvanceOldestClogXid(TransactionId oldest_datfrozenxid);
extern bool ForceTransactionIdLimitUpdate(void);
extern Oid GetNewObjectId(void);
extern void StopGeneratingPinnedObjectIds(void);
#ifdef USE_ASSERT_CHECKING
extern void AssertTransactionIdInAllowableRange(TransactionId xid);