diff options
Diffstat (limited to 'src/include/utils/snapmgr.h')
| -rw-r--r-- | src/include/utils/snapmgr.h | 37 |
1 files changed, 28 insertions, 9 deletions
diff --git a/src/include/utils/snapmgr.h b/src/include/utils/snapmgr.h index ffb4ba3adfb..b6b403e2931 100644 --- a/src/include/utils/snapmgr.h +++ b/src/include/utils/snapmgr.h @@ -52,13 +52,12 @@ extern Size SnapMgrShmemSize(void); extern void SnapMgrInit(void); extern TimestampTz GetSnapshotCurrentTimestamp(void); extern TimestampTz GetOldSnapshotThresholdTimestamp(void); +extern void SnapshotTooOldMagicForTest(void); extern bool FirstSnapshotSet; extern PGDLLIMPORT TransactionId TransactionXmin; extern PGDLLIMPORT TransactionId RecentXmin; -extern PGDLLIMPORT TransactionId RecentGlobalXmin; -extern PGDLLIMPORT TransactionId RecentGlobalDataXmin; /* Variables representing various special snapshot semantics */ extern PGDLLIMPORT SnapshotData SnapshotSelfData; @@ -78,11 +77,12 @@ extern PGDLLIMPORT SnapshotData CatalogSnapshotData; /* * Similarly, some initialization is required for a NonVacuumable snapshot. - * The caller must supply the xmin horizon to use (e.g., RecentGlobalXmin). + * The caller must supply the visibility cutoff state to use (c.f. + * GlobalVisTestFor()). */ -#define InitNonVacuumableSnapshot(snapshotdata, xmin_horizon) \ +#define InitNonVacuumableSnapshot(snapshotdata, vistestp) \ ((snapshotdata).snapshot_type = SNAPSHOT_NON_VACUUMABLE, \ - (snapshotdata).xmin = (xmin_horizon)) + (snapshotdata).vistest = (vistestp)) /* * Similarly, some initialization is required for SnapshotToast. We need @@ -98,6 +98,11 @@ extern PGDLLIMPORT SnapshotData CatalogSnapshotData; ((snapshot)->snapshot_type == SNAPSHOT_MVCC || \ (snapshot)->snapshot_type == SNAPSHOT_HISTORIC_MVCC) +static inline bool +OldSnapshotThresholdActive(void) +{ + return old_snapshot_threshold >= 0; +} extern Snapshot GetTransactionSnapshot(void); extern Snapshot GetLatestSnapshot(void); @@ -121,8 +126,6 @@ extern void UnregisterSnapshot(Snapshot snapshot); extern Snapshot RegisterSnapshotOnOwner(Snapshot snapshot, ResourceOwner owner); extern void UnregisterSnapshotFromOwner(Snapshot snapshot, ResourceOwner owner); -extern FullTransactionId GetFullRecentGlobalXmin(void); - extern void AtSubCommit_Snapshot(int level); extern void AtSubAbort_Snapshot(int level); extern void AtEOXact_Snapshot(bool isCommit, bool resetXmin); @@ -131,14 +134,30 @@ extern void ImportSnapshot(const char *idstr); extern bool XactHasExportedSnapshots(void); extern void DeleteAllExportedSnapshotFiles(void); extern bool ThereAreNoPriorRegisteredSnapshots(void); -extern TransactionId TransactionIdLimitedForOldSnapshots(TransactionId recentXmin, - Relation relation); +extern bool TransactionIdLimitedForOldSnapshots(TransactionId recentXmin, + Relation relation, + TransactionId *limit_xid, + TimestampTz *limit_ts); +extern void SetOldSnapshotThresholdTimestamp(TimestampTz ts, TransactionId xlimit); extern void MaintainOldSnapshotTimeMapping(TimestampTz whenTaken, TransactionId xmin); extern char *ExportSnapshot(Snapshot snapshot); /* + * These live in procarray.c because they're intimately linked to the + * procarray contents, but thematically they better fit into snapmgr.h. + */ +typedef struct GlobalVisState GlobalVisState; +extern GlobalVisState *GlobalVisTestFor(Relation rel); +extern bool GlobalVisTestIsRemovableXid(GlobalVisState *state, TransactionId xid); +extern bool GlobalVisTestIsRemovableFullXid(GlobalVisState *state, FullTransactionId fxid); +extern FullTransactionId GlobalVisTestNonRemovableFullHorizon(GlobalVisState *state); +extern TransactionId GlobalVisTestNonRemovableHorizon(GlobalVisState *state); +extern bool GlobalVisCheckRemovableXid(Relation rel, TransactionId xid); +extern bool GlobalVisIsRemovableFullXid(Relation rel, FullTransactionId fxid); + +/* * Utility functions for implementing visibility routines in table AMs. */ extern bool XidInMVCCSnapshot(TransactionId xid, Snapshot snapshot); |