From a7a19f52063fd8baa38a25948d3d9c6a6d614196 Mon Sep 17 00:00:00 2001 From: Andres Freund Date: Mon, 6 Apr 2020 21:28:55 -0700 Subject: [PATCH v7 10/11] Remove now unused PGXACT. --- src/include/storage/proc.h | 15 --------------- src/backend/access/transam/twophase.c | 6 +++--- src/backend/storage/ipc/procarray.c | 24 +++++++++--------------- src/backend/storage/lmgr/proc.c | 21 +-------------------- src/tools/pgindent/typedefs.list | 1 - 5 files changed, 13 insertions(+), 54 deletions(-) diff --git a/src/include/storage/proc.h b/src/include/storage/proc.h index 3cd48382260..e225efa8ece 100644 --- a/src/include/storage/proc.h +++ b/src/include/storage/proc.h @@ -232,19 +232,6 @@ 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 -{ -} PGXACT; /* * There is one ProcGlobal struct for the whole database cluster. @@ -260,8 +247,6 @@ 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; /* * Arrays with per-backend information that is hotly accessed, indexed by diff --git a/src/backend/access/transam/twophase.c b/src/backend/access/transam/twophase.c index f802544d378..d03fbefd5d2 100644 --- a/src/backend/access/transam/twophase.c +++ b/src/backend/access/transam/twophase.c @@ -21,9 +21,9 @@ * GIDs and aborts the transaction if there already is a global * transaction in prepared state with the same GID. * - * A global transaction (gxact) also has dummy PGXACT and PGPROC; this is - * what keeps the XID considered running by TransactionIdIsInProgress. - * It is also convenient as a PGPROC to hook the gxact's locks to. + * A global transaction (gxact) also has dummy PGPROC; this is what keeps + * the XID considered running by TransactionIdIsInProgress. It is also + * convenient as a PGPROC to hook the gxact's locks to. * * Information to recover prepared transactions in case of crash is * now stored in WAL for the common case. In some cases there will be diff --git a/src/backend/storage/ipc/procarray.c b/src/backend/storage/ipc/procarray.c index 6de0590dbec..92ed8d20519 100644 --- a/src/backend/storage/ipc/procarray.c +++ b/src/backend/storage/ipc/procarray.c @@ -4,9 +4,10 @@ * POSTGRES process array code. * * - * This module maintains arrays of the PGPROC and PGXACT structures for all - * active backends. Although there are several uses for this, the principal - * one is as a means of determining the set of currently running transactions. + * This module maintains arrays of PGPROC substructures, as well as associated + * arrays in ProcGlobal, for all active backends. Although there are several + * uses for this, the principal one is as a means of determining the set of + * currently running transactions. * * Because of various subtle race conditions it is critical that a backend * hold the correct locks while setting or clearing its xid (in @@ -97,7 +98,7 @@ typedef struct ProcArrayStruct /* oldest catalog xmin of any replication slot */ TransactionId replication_slot_catalog_xmin; - /* indexes into allPgXact[], has PROCARRAY_MAXPROCS entries */ + /* indexes into allProcs[], has PROCARRAY_MAXPROCS entries */ int pgprocnos[FLEXIBLE_ARRAY_MEMBER]; } ProcArrayStruct; @@ -196,7 +197,6 @@ typedef struct ComputedHorizons static ProcArrayStruct *procArray; static PGPROC *allProcs; -static PGXACT *allPgXact; /* * Bookkeeping for tracking emulated transactions in recovery @@ -283,8 +283,7 @@ static int KnownAssignedXidsGetAndSetXmin(TransactionId *xarray, static TransactionId KnownAssignedXidsGetOldestXmin(void); static void KnownAssignedXidsDisplay(int trace_level); static void KnownAssignedXidsReset(void); -static inline void ProcArrayEndTransactionInternal(PGPROC *proc, - PGXACT *pgxact, TransactionId latestXid); +static inline void ProcArrayEndTransactionInternal(PGPROC *proc, TransactionId latestXid); static void ProcArrayGroupClearXid(PGPROC *proc, TransactionId latestXid); static void MaintainLatestCompletedXid(TransactionId latestXid); @@ -369,7 +368,6 @@ CreateSharedProcArray(void) } allProcs = ProcGlobal->allProcs; - allPgXact = ProcGlobal->allPgXact; /* Create or attach to the KnownAssignedXids arrays too, if needed */ if (EnableHotStandby) @@ -572,8 +570,6 @@ ProcArrayRemove(PGPROC *proc, TransactionId latestXid) void ProcArrayEndTransaction(PGPROC *proc, TransactionId latestXid) { - PGXACT *pgxact = &allPgXact[proc->pgprocno]; - if (TransactionIdIsValid(latestXid)) { /* @@ -591,7 +587,7 @@ ProcArrayEndTransaction(PGPROC *proc, TransactionId latestXid) */ if (LWLockConditionalAcquire(ProcArrayLock, LW_EXCLUSIVE)) { - ProcArrayEndTransactionInternal(proc, pgxact, latestXid); + ProcArrayEndTransactionInternal(proc, latestXid); LWLockRelease(ProcArrayLock); } else @@ -631,8 +627,7 @@ ProcArrayEndTransaction(PGPROC *proc, TransactionId latestXid) * We don't do any locking here; caller must handle that. */ static inline void -ProcArrayEndTransactionInternal(PGPROC *proc, PGXACT *pgxact, - TransactionId latestXid) +ProcArrayEndTransactionInternal(PGPROC *proc, TransactionId latestXid) { size_t pgxactoff = proc->pgxactoff; @@ -753,9 +748,8 @@ ProcArrayGroupClearXid(PGPROC *proc, TransactionId latestXid) while (nextidx != INVALID_PGPROCNO) { PGPROC *proc = &allProcs[nextidx]; - PGXACT *pgxact = &allPgXact[nextidx]; - ProcArrayEndTransactionInternal(proc, pgxact, proc->procArrayGroupMemberXid); + ProcArrayEndTransactionInternal(proc, proc->procArrayGroupMemberXid); /* Move to next proc in list. */ nextidx = pg_atomic_read_u32(&proc->procArrayGroupNext); diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c index c619250318b..34a6c6b1536 100644 --- a/src/backend/storage/lmgr/proc.c +++ b/src/backend/storage/lmgr/proc.c @@ -63,9 +63,8 @@ int LockTimeout = 0; int IdleInTransactionSessionTimeout = 0; bool log_lock_waits = false; -/* Pointer to this process's PGPROC and PGXACT structs, if any */ +/* Pointer to this process's PGPROC struct, if any */ PGPROC *MyProc = NULL; -PGXACT *MyPgXact = NULL; /* * This spinlock protects the freelist of recycled PGPROC structures. @@ -109,9 +108,6 @@ ProcGlobalShmemSize(void) size = add_size(size, mul_size(TotalProcs, sizeof(PGPROC))); size = add_size(size, sizeof(slock_t)); - size = add_size(size, mul_size(MaxBackends, sizeof(PGXACT))); - size = add_size(size, mul_size(NUM_AUXILIARY_PROCS, sizeof(PGXACT))); - size = add_size(size, mul_size(max_prepared_xacts, sizeof(PGXACT))); size = add_size(size, mul_size(TotalProcs, sizeof(*ProcGlobal->xids))); size = add_size(size, mul_size(TotalProcs, sizeof(*ProcGlobal->subxidStates))); size = add_size(size, mul_size(TotalProcs, sizeof(*ProcGlobal->vacuumFlags))); @@ -161,7 +157,6 @@ void InitProcGlobal(void) { PGPROC *procs; - PGXACT *pgxacts; int i, j; bool found; @@ -202,18 +197,6 @@ InitProcGlobal(void) /* XXX allProcCount isn't really all of them; it excludes prepared xacts */ ProcGlobal->allProcCount = MaxBackends + NUM_AUXILIARY_PROCS; - /* - * Also allocate a separate array of PGXACT structures. This is separate - * from the main PGPROC array so that the most heavily accessed data is - * stored contiguously in memory in as few cache lines as possible. This - * provides significant performance benefits, especially on a - * multiprocessor system. There is one PGXACT structure for every PGPROC - * structure. - */ - pgxacts = (PGXACT *) ShmemAlloc(TotalProcs * sizeof(PGXACT)); - MemSet(pgxacts, 0, TotalProcs * sizeof(PGXACT)); - ProcGlobal->allPgXact = pgxacts; - /* * Also allocate a separate arrays for data that is frequently (e.g. by * GetSnapshotData()) accessed from outside a backend. There is one entry @@ -382,7 +365,6 @@ InitProcess(void) (errcode(ERRCODE_TOO_MANY_CONNECTIONS), errmsg("sorry, too many clients already"))); } - MyPgXact = &ProcGlobal->allPgXact[MyProc->pgprocno]; /* * Cross-check that the PGPROC is of the type we expect; if this were not @@ -579,7 +561,6 @@ InitAuxiliaryProcess(void) ((volatile PGPROC *) auxproc)->pid = MyProcPid; MyProc = auxproc; - MyPgXact = &ProcGlobal->allPgXact[auxproc->pgprocno]; SpinLockRelease(ProcStructLock); diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list index 525d58e7f01..3dd5fedcf7b 100644 --- a/src/tools/pgindent/typedefs.list +++ b/src/tools/pgindent/typedefs.list @@ -1508,7 +1508,6 @@ PGSetenvStatusType PGShmemHeader PGTransactionStatusType PGVerbosity -PGXACT PG_Locale_Strategy PG_Lock_Status PG_init_t -- 2.25.0.114.g5b0ca878e0