codekingpro/portable-devtools

1/*2 * xlog.h3 *4 * PostgreSQL write-ahead log manager5 *6 * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group7 * Portions Copyright (c) 1994, Regents of the University of California8 *9 * src/include/access/xlog.h10 */11#ifndef XLOG_H12#define XLOG_H13 14#include "access/xlogbackup.h"15#include "access/xlogdefs.h"16#include "datatype/timestamp.h"17#include "lib/stringinfo.h"18#include "nodes/pg_list.h"19 20 21/* Sync methods */22#define SYNC_METHOD_FSYNC		023#define SYNC_METHOD_FDATASYNC	124#define SYNC_METHOD_OPEN		2	/* for O_SYNC */25#define SYNC_METHOD_FSYNC_WRITETHROUGH	326#define SYNC_METHOD_OPEN_DSYNC	4	/* for O_DSYNC */27extern PGDLLIMPORT int sync_method;28 29extern PGDLLIMPORT XLogRecPtr ProcLastRecPtr;30extern PGDLLIMPORT XLogRecPtr XactLastRecEnd;31extern PGDLLIMPORT XLogRecPtr XactLastCommitEnd;32 33/* these variables are GUC parameters related to XLOG */34extern PGDLLIMPORT int wal_segment_size;35extern PGDLLIMPORT int min_wal_size_mb;36extern PGDLLIMPORT int max_wal_size_mb;37extern PGDLLIMPORT int wal_keep_size_mb;38extern PGDLLIMPORT int max_slot_wal_keep_size_mb;39extern PGDLLIMPORT int XLOGbuffers;40extern PGDLLIMPORT int XLogArchiveTimeout;41extern PGDLLIMPORT int wal_retrieve_retry_interval;42extern PGDLLIMPORT char *XLogArchiveCommand;43extern PGDLLIMPORT bool EnableHotStandby;44extern PGDLLIMPORT bool fullPageWrites;45extern PGDLLIMPORT bool wal_log_hints;46extern PGDLLIMPORT int wal_compression;47extern PGDLLIMPORT bool wal_init_zero;48extern PGDLLIMPORT bool wal_recycle;49extern PGDLLIMPORT bool *wal_consistency_checking;50extern PGDLLIMPORT char *wal_consistency_checking_string;51extern PGDLLIMPORT bool log_checkpoints;52extern PGDLLIMPORT bool track_wal_io_timing;53extern PGDLLIMPORT int wal_decode_buffer_size;54 55extern PGDLLIMPORT int CheckPointSegments;56 57/* Archive modes */58typedef enum ArchiveMode59{60	ARCHIVE_MODE_OFF = 0,		/* disabled */61	ARCHIVE_MODE_ON,			/* enabled while server is running normally */62	ARCHIVE_MODE_ALWAYS			/* enabled always (even during recovery) */63} ArchiveMode;64extern PGDLLIMPORT int XLogArchiveMode;65 66/* WAL levels */67typedef enum WalLevel68{69	WAL_LEVEL_MINIMAL = 0,70	WAL_LEVEL_REPLICA,71	WAL_LEVEL_LOGICAL72} WalLevel;73 74/* Compression algorithms for WAL */75typedef enum WalCompression76{77	WAL_COMPRESSION_NONE = 0,78	WAL_COMPRESSION_PGLZ,79	WAL_COMPRESSION_LZ4,80	WAL_COMPRESSION_ZSTD81} WalCompression;82 83/* Recovery states */84typedef enum RecoveryState85{86	RECOVERY_STATE_CRASH = 0,	/* crash recovery */87	RECOVERY_STATE_ARCHIVE,		/* archive recovery */88	RECOVERY_STATE_DONE			/* currently in production */89} RecoveryState;90 91extern PGDLLIMPORT int wal_level;92 93/* Is WAL archiving enabled (always or only while server is running normally)? */94#define XLogArchivingActive() \95	(AssertMacro(XLogArchiveMode == ARCHIVE_MODE_OFF || wal_level >= WAL_LEVEL_REPLICA), XLogArchiveMode > ARCHIVE_MODE_OFF)96/* Is WAL archiving enabled always (even during recovery)? */97#define XLogArchivingAlways() \98	(AssertMacro(XLogArchiveMode == ARCHIVE_MODE_OFF || wal_level >= WAL_LEVEL_REPLICA), XLogArchiveMode == ARCHIVE_MODE_ALWAYS)99 100/*101 * Is WAL-logging necessary for archival or log-shipping, or can we skip102 * WAL-logging if we fsync() the data before committing instead?103 */104#define XLogIsNeeded() (wal_level >= WAL_LEVEL_REPLICA)105 106/*107 * Is a full-page image needed for hint bit updates?108 *109 * Normally, we don't WAL-log hint bit updates, but if checksums are enabled,110 * we have to protect them against torn page writes.  When you only set111 * individual bits on a page, it's still consistent no matter what combination112 * of the bits make it to disk, but the checksum wouldn't match.  Also WAL-log113 * them if forced by wal_log_hints=on.114 */115#define XLogHintBitIsNeeded() (DataChecksumsEnabled() || wal_log_hints)116 117/* Do we need to WAL-log information required only for Hot Standby and logical replication? */118#define XLogStandbyInfoActive() (wal_level >= WAL_LEVEL_REPLICA)119 120/* Do we need to WAL-log information required only for logical replication? */121#define XLogLogicalInfoActive() (wal_level >= WAL_LEVEL_LOGICAL)122 123#ifdef WAL_DEBUG124extern PGDLLIMPORT bool XLOG_DEBUG;125#endif126 127/*128 * OR-able request flag bits for checkpoints.  The "cause" bits are used only129 * for logging purposes.  Note: the flags must be defined so that it's130 * sensible to OR together request flags arising from different requestors.131 */132 133/* These directly affect the behavior of CreateCheckPoint and subsidiaries */134#define CHECKPOINT_IS_SHUTDOWN	0x0001	/* Checkpoint is for shutdown */135#define CHECKPOINT_END_OF_RECOVERY	0x0002	/* Like shutdown checkpoint, but136											 * issued at end of WAL recovery */137#define CHECKPOINT_IMMEDIATE	0x0004	/* Do it without delays */138#define CHECKPOINT_FORCE		0x0008	/* Force even if no activity */139#define CHECKPOINT_FLUSH_ALL	0x0010	/* Flush all pages, including those140										 * belonging to unlogged tables */141/* These are important to RequestCheckpoint */142#define CHECKPOINT_WAIT			0x0020	/* Wait for completion */143#define CHECKPOINT_REQUESTED	0x0040	/* Checkpoint request has been made */144/* These indicate the cause of a checkpoint request */145#define CHECKPOINT_CAUSE_XLOG	0x0080	/* XLOG consumption */146#define CHECKPOINT_CAUSE_TIME	0x0100	/* Elapsed time */147 148/*149 * Flag bits for the record being inserted, set using XLogSetRecordFlags().150 */151#define XLOG_INCLUDE_ORIGIN		0x01	/* include the replication origin */152#define XLOG_MARK_UNIMPORTANT	0x02	/* record not important for durability */153 154 155/* Checkpoint statistics */156typedef struct CheckpointStatsData157{158	TimestampTz ckpt_start_t;	/* start of checkpoint */159	TimestampTz ckpt_write_t;	/* start of flushing buffers */160	TimestampTz ckpt_sync_t;	/* start of fsyncs */161	TimestampTz ckpt_sync_end_t;	/* end of fsyncs */162	TimestampTz ckpt_end_t;		/* end of checkpoint */163 164	int			ckpt_bufs_written;	/* # of buffers written */165 166	int			ckpt_segs_added;	/* # of new xlog segments created */167	int			ckpt_segs_removed;	/* # of xlog segments deleted */168	int			ckpt_segs_recycled; /* # of xlog segments recycled */169 170	int			ckpt_sync_rels; /* # of relations synced */171	uint64		ckpt_longest_sync;	/* Longest sync for one relation */172	uint64		ckpt_agg_sync_time; /* The sum of all the individual sync173									 * times, which is not necessarily the174									 * same as the total elapsed time for the175									 * entire sync phase. */176} CheckpointStatsData;177 178extern PGDLLIMPORT CheckpointStatsData CheckpointStats;179 180/*181 * GetWALAvailability return codes182 */183typedef enum WALAvailability184{185	WALAVAIL_INVALID_LSN,		/* parameter error */186	WALAVAIL_RESERVED,			/* WAL segment is within max_wal_size */187	WALAVAIL_EXTENDED,			/* WAL segment is reserved by a slot or188								 * wal_keep_size */189	WALAVAIL_UNRESERVED,		/* no longer reserved, but not removed yet */190	WALAVAIL_REMOVED			/* WAL segment has been removed */191} WALAvailability;192 193struct XLogRecData;194struct XLogReaderState;195 196extern XLogRecPtr XLogInsertRecord(struct XLogRecData *rdata,197								   XLogRecPtr fpw_lsn,198								   uint8 flags,199								   int num_fpi,200								   bool topxid_included);201extern void XLogFlush(XLogRecPtr record);202extern bool XLogBackgroundFlush(void);203extern bool XLogNeedsFlush(XLogRecPtr record);204extern int	XLogFileInit(XLogSegNo logsegno, TimeLineID logtli);205extern int	XLogFileOpen(XLogSegNo segno, TimeLineID tli);206 207extern void CheckXLogRemoved(XLogSegNo segno, TimeLineID tli);208extern XLogSegNo XLogGetLastRemovedSegno(void);209extern void XLogSetAsyncXactLSN(XLogRecPtr asyncXactLSN);210extern void XLogSetReplicationSlotMinimumLSN(XLogRecPtr lsn);211 212extern void xlog_redo(struct XLogReaderState *record);213extern void xlog_desc(StringInfo buf, struct XLogReaderState *record);214extern const char *xlog_identify(uint8 info);215 216extern void issue_xlog_fsync(int fd, XLogSegNo segno, TimeLineID tli);217 218extern bool RecoveryInProgress(void);219extern RecoveryState GetRecoveryState(void);220extern bool XLogInsertAllowed(void);221extern XLogRecPtr GetXLogInsertRecPtr(void);222extern XLogRecPtr GetXLogWriteRecPtr(void);223 224extern uint64 GetSystemIdentifier(void);225extern char *GetMockAuthenticationNonce(void);226extern bool DataChecksumsEnabled(void);227extern XLogRecPtr GetFakeLSNForUnloggedRel(void);228extern Size XLOGShmemSize(void);229extern void XLOGShmemInit(void);230extern void BootStrapXLOG(void);231extern void InitializeWalConsistencyChecking(void);232extern void LocalProcessControlFile(bool reset);233extern WalLevel GetActiveWalLevelOnStandby(void);234extern void StartupXLOG(void);235extern void ShutdownXLOG(int code, Datum arg);236extern void CreateCheckPoint(int flags);237extern bool CreateRestartPoint(int flags);238extern WALAvailability GetWALAvailability(XLogRecPtr targetLSN);239extern void XLogPutNextOid(Oid nextOid);240extern XLogRecPtr XLogRestorePoint(const char *rpName);241extern void UpdateFullPageWrites(void);242extern void GetFullPageWriteInfo(XLogRecPtr *RedoRecPtr_p, bool *doPageWrites_p);243extern XLogRecPtr GetRedoRecPtr(void);244extern XLogRecPtr GetInsertRecPtr(void);245extern XLogRecPtr GetFlushRecPtr(TimeLineID *insertTLI);246extern TimeLineID GetWALInsertionTimeLine(void);247extern XLogRecPtr GetLastImportantRecPtr(void);248 249extern void SetWalWriterSleeping(bool sleeping);250 251/*252 * Routines used by xlogrecovery.c to call back into xlog.c during recovery.253 */254extern void RemoveNonParentXlogFiles(XLogRecPtr switchpoint, TimeLineID newTLI);255extern bool XLogCheckpointNeeded(XLogSegNo new_segno);256extern void SwitchIntoArchiveRecovery(XLogRecPtr EndRecPtr, TimeLineID replayTLI);257extern void ReachedEndOfBackup(XLogRecPtr EndRecPtr, TimeLineID tli);258extern void SetInstallXLogFileSegmentActive(void);259extern bool IsInstallXLogFileSegmentActive(void);260extern void XLogShutdownWalRcv(void);261 262/*263 * Routines to start, stop, and get status of a base backup.264 */265 266/*267 * Session-level status of base backups268 *269 * This is used in parallel with the shared memory status to control parallel270 * execution of base backup functions for a given session, be it a backend271 * dedicated to replication or a normal backend connected to a database. The272 * update of the session-level status happens at the same time as the shared273 * memory counters to keep a consistent global and local state of the backups274 * running.275 */276typedef enum SessionBackupState277{278	SESSION_BACKUP_NONE,279	SESSION_BACKUP_RUNNING,280} SessionBackupState;281 282extern void do_pg_backup_start(const char *backupidstr, bool fast,283							   List **tablespaces, BackupState *state,284							   StringInfo tblspcmapfile);285extern void do_pg_backup_stop(BackupState *state, bool waitforarchive);286extern void do_pg_abort_backup(int code, Datum arg);287extern void register_persistent_abort_backup_handler(void);288extern SessionBackupState get_backup_status(void);289 290/* File path names (all relative to $PGDATA) */291#define RECOVERY_SIGNAL_FILE	"recovery.signal"292#define STANDBY_SIGNAL_FILE		"standby.signal"293#define BACKUP_LABEL_FILE		"backup_label"294#define BACKUP_LABEL_OLD		"backup_label.old"295 296#define TABLESPACE_MAP			"tablespace_map"297#define TABLESPACE_MAP_OLD		"tablespace_map.old"298 299/* files to signal promotion to primary */300#define PROMOTE_SIGNAL_FILE		"promote"301 302#endif							/* XLOG_H */303