diff options
Diffstat (limited to 'src/include/storage/proc.h')
| -rw-r--r-- | src/include/storage/proc.h | 34 |
1 files changed, 16 insertions, 18 deletions
diff --git a/src/include/storage/proc.h b/src/include/storage/proc.h index 9f3a8b518eb..9c9a50ae457 100644 --- a/src/include/storage/proc.h +++ b/src/include/storage/proc.h @@ -35,6 +35,14 @@ */ #define PGPROC_MAX_CACHED_SUBXIDS 64 /* XXX guessed-at value */ +typedef struct XidCacheStatus +{ + /* number of cached subxids, never more than PGPROC_MAX_CACHED_SUBXIDS */ + uint8 count; + /* has PGPROC->subxids overflowed */ + bool overflowed; +} XidCacheStatus; + struct XidCache { TransactionId xids[PGPROC_MAX_CACHED_SUBXIDS]; @@ -187,6 +195,8 @@ struct PGPROC */ SHM_QUEUE myProcLocks[NUM_LOCK_PARTITIONS]; + XidCacheStatus subxidStatus; /* mirrored with + * ProcGlobal->subxidStates[i] */ struct XidCache subxids; /* cache for subtransaction XIDs */ /* Support for group XID clearing. */ @@ -235,22 +245,6 @@ struct PGPROC extern PGDLLIMPORT PGPROC *MyProc; -extern PGDLLIMPORT struct PGXACT *MyPgXact; - -/* - * Prior to PostgreSQL 9.2, the fields below were stored as part of the - * PGPROC. However, benchmarking revealed that packing these particular - * members into a separate array as tightly as possible sped up GetSnapshotData - * considerably on systems with many CPU cores, by reducing the number of - * cache lines needing to be fetched. Thus, think very carefully before adding - * anything else here. - */ -typedef struct PGXACT -{ - bool overflowed; - - uint8 nxids; -} PGXACT; /* * There is one ProcGlobal struct for the whole database cluster. @@ -310,13 +304,17 @@ typedef struct PROC_HDR { /* Array of PGPROC structures (not including dummies for prepared txns) */ PGPROC *allProcs; - /* Array of PGXACT structures (not including dummies for prepared txns) */ - PGXACT *allPgXact; /* Array mirroring PGPROC.xid for each PGPROC currently in the procarray */ TransactionId *xids; /* + * Array mirroring PGPROC.subxidStatus for each PGPROC currently in the + * procarray. + */ + XidCacheStatus *subxidStates; + + /* * Array mirroring PGPROC.vacuumFlags for each PGPROC currently in the * procarray. */ |