src/include/storage/standby.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * standby.h
   4  *        Definitions for hot standby mode.
   5  *
   6  *
   7  * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
   8  * Portions Copyright (c) 1994, Regents of the University of California
   9  *
  10  * src/include/storage/standby.h
  11  *
  12  *-------------------------------------------------------------------------
  13  */
  14 #ifndef STANDBY_H
  15 #define STANDBY_H
  16
  17 #include "datatype/timestamp.h"
  18 #include "storage/lock.h"
  19 #include "storage/procsignal.h"
  20 #include "storage/relfilenode.h"
  21 #include "storage/standbydefs.h"
  22
  23 /* User-settable GUC parameters */
  24 extern int      vacuum_defer_cleanup_age;
  25 extern int      max_standby_archive_delay;
  26 extern int      max_standby_streaming_delay;
  27 extern bool log_recovery_conflict_waits;
  28
  29 extern void InitRecoveryTransactionEnvironment(void);
  30 extern void ShutdownRecoveryTransactionEnvironment(void);
  31
  32 extern void ResolveRecoveryConflictWithSnapshot(TransactionId latestRemovedXid,
  33                                                                                                 RelFileNode node);
  34 extern void ResolveRecoveryConflictWithSnapshotFullXid(FullTransactionId latestRemovedFullXid,
  35                                                                                                            RelFileNode node);
  36 extern void ResolveRecoveryConflictWithTablespace(Oid tsid);
  37 extern void ResolveRecoveryConflictWithDatabase(Oid dbid);
  38
  39 extern void ResolveRecoveryConflictWithLock(LOCKTAG locktag, bool logging_conflict);
  40 extern void ResolveRecoveryConflictWithBufferPin(void);
  41 extern void CheckRecoveryConflictDeadlock(void);
  42 extern void StandbyDeadLockHandler(void);
  43 extern void StandbyTimeoutHandler(void);
  44 extern void StandbyLockTimeoutHandler(void);
  45 extern void LogRecoveryConflict(ProcSignalReason reason, TimestampTz wait_start,
  46                                                                 TimestampTz cur_ts, VirtualTransactionId *wait_list,
  47                                                                 bool still_waiting);
  48
  49 /*
  50  * Standby Rmgr (RM_STANDBY_ID)
  51  *
  52  * Standby recovery manager exists to perform actions that are required
  53  * to make hot standby work. That includes logging AccessExclusiveLocks taken
  54  * by transactions and running-xacts snapshots.
  55  */
  56 extern void StandbyAcquireAccessExclusiveLock(TransactionId xid, Oid dbOid, Oid relOid);
  57 extern void StandbyReleaseLockTree(TransactionId xid,
  58                                                                    int nsubxids, TransactionId *subxids);
  59 extern void StandbyReleaseAllLocks(void);
  60 extern void StandbyReleaseOldLocks(TransactionId oldxid);
  61
  62 #define MinSizeOfXactRunningXacts offsetof(xl_running_xacts, xids)
  63
  64
  65 /*
  66  * Declarations for GetRunningTransactionData(). Similar to Snapshots, but
  67  * not quite. This has nothing at all to do with visibility on this server,
  68  * so this is completely separate from snapmgr.c and snapmgr.h.
  69  * This data is important for creating the initial snapshot state on a
  70  * standby server. We need lots more information than a normal snapshot,
  71  * hence we use a specific data structure for our needs. This data
  72  * is written to WAL as a separate record immediately after each
  73  * checkpoint. That means that wherever we start a standby from we will
  74  * almost immediately see the data we need to begin executing queries.
  75  */
  76
  77 typedef struct RunningTransactionsData
  78 {
  79         int                     xcnt;                   /* # of xact ids in xids[] */
  80         int                     subxcnt;                /* # of subxact ids in xids[] */
  81         bool            subxid_overflow;        /* snapshot overflowed, subxids missing */
  82         TransactionId nextXid;          /* xid from ShmemVariableCache->nextXid */
  83         TransactionId oldestRunningXid; /* *not* oldestXmin */
  84         TransactionId latestCompletedXid;       /* so we can set xmax */
  85
  86         TransactionId *xids;            /* array of (sub)xids still running */
  87 } RunningTransactionsData;
  88
  89 typedef RunningTransactionsData *RunningTransactions;
  90
  91 extern void LogAccessExclusiveLock(Oid dbOid, Oid relOid);
  92 extern void LogAccessExclusiveLockPrepare(void);
  93
  94 extern XLogRecPtr LogStandbySnapshot(void);
  95 extern void LogStandbyInvalidations(int nmsgs, SharedInvalidationMessage *msgs,
  96                                                                         bool relcacheInitFileInval);
  97
  98 #endif                                                  /* STANDBY_H */