acl/lib_dict/bdb/include/rep.h

318 lines
12 KiB
C

/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 2001-2004
* Sleepycat Software. All rights reserved.
*/
#ifndef _REP_H_
#define _REP_H_
#include "dbinc_auto/rep_auto.h"
#define REP_ALIVE 1 /* I am alive message. */
#define REP_ALIVE_REQ 2 /* Request for alive messages. */
#define REP_ALL_REQ 3 /* Request all log records greater than LSN. */
#define REP_DUPMASTER 4 /* Duplicate master detected; propagate. */
#define REP_FILE 5 /* Page of a database file. NOTUSED */
#define REP_FILE_FAIL 6 /* File requested does not exist. */
#define REP_FILE_REQ 7 /* Request for a database file. NOTUSED */
#define REP_LOG 8 /* Log record. */
#define REP_LOG_MORE 9 /* There are more log records to request. */
#define REP_LOG_REQ 10 /* Request for a log record. */
#define REP_MASTER_REQ 11 /* Who is the master */
#define REP_NEWCLIENT 12 /* Announces the presence of a new client. */
#define REP_NEWFILE 13 /* Announce a log file change. */
#define REP_NEWMASTER 14 /* Announces who the master is. */
#define REP_NEWSITE 15 /* Announces that a site has heard from a new
* site; like NEWCLIENT, but indirect. A
* NEWCLIENT message comes directly from the new
* client while a NEWSITE comes indirectly from
* someone who heard about a NEWSITE.
*/
#define REP_PAGE 16 /* Database page. */
#define REP_PAGE_FAIL 17 /* Requested page does not exist. */
#define REP_PAGE_MORE 18 /* There are more pages to request. */
#define REP_PAGE_REQ 19 /* Request for a database page. */
#define REP_UPDATE 20 /* Environment hotcopy information. */
#define REP_UPDATE_REQ 21 /* Request for hotcopy information. */
#define REP_VERIFY 22 /* A log record for verification. */
#define REP_VERIFY_FAIL 23 /* The client is outdated. */
#define REP_VERIFY_REQ 24 /* Request for a log record to verify. */
#define REP_VOTE1 25 /* Send out your information for an election. */
#define REP_VOTE2 26 /* Send a "you are master" vote. */
/*
* REP_PRINT_MESSAGE
* A function to print a debugging message.
*
* RPRINT
* A macro for debug printing. Takes as an arg the arg set for __db_msg.
*
* !!! This function assumes a local DB_MSGBUF variable called 'mb'.
*/
#ifdef DIAGNOSTIC
#define REP_PRINT_MESSAGE(dbenv, eid, rp, str) \
__rep_print_message(dbenv, eid, rp, str)
#define RPRINT(e, r, x) do { \
if (FLD_ISSET((e)->verbose, DB_VERB_REPLICATION)) { \
DB_MSGBUF_INIT(&mb); \
if ((e)->db_errpfx == NULL) { \
if (F_ISSET((r), REP_F_CLIENT)) \
__db_msgadd((e), &mb, "CLIENT: "); \
else if (F_ISSET((r), REP_F_MASTER)) \
__db_msgadd((e), &mb, "MASTER: "); \
else \
__db_msgadd((e), &mb, "REP_UNDEF: "); \
} else \
__db_msgadd((e), &mb, "%s: ",(e)->db_errpfx); \
__db_msgadd x; \
DB_MSGBUF_FLUSH((e), &mb); \
} \
} while (0)
#else
#define REP_PRINT_MESSAGE(dbenv, eid, rp, str)
#define RPRINT(e, r, x)
#endif
/*
* Election gen file name
* The file contains an egen number for an election this client
* has NOT participated in. I.e. it is the number of a future
* election. We create it when we create the rep region, if it
* doesn't already exist and initialize egen to 1. If it does
* exist, we read it when we create the rep region. We write it
* immediately before sending our VOTE1 in an election. That way,
* if a client has ever sent a vote for any election, the file is
* already going to be updated to reflect a future election,
* should it crash.
*/
#define REP_EGENNAME "__db.rep.egen"
/*
* Database types for __rep_client_dbinit
*/
typedef enum {
REP_DB, /* Log record database. */
REP_PG /* Pg database. */
} repdb_t;
/* Shared replication structure. */
typedef struct __rep {
/*
* Due to alignment constraints on some architectures (e.g. HP-UX),
* DB_MUTEXes must be the first element of shalloced structures,
* and as a corollary there can be only one per structure. Thus,
* db_mutex_off points to a mutex in a separately-allocated chunk.
*/
DB_MUTEX mutex; /* Region lock. */
roff_t db_mutex_off; /* Client database mutex. */
roff_t tally_off; /* Offset of the tally region. */
roff_t v2tally_off; /* Offset of the vote2 tally region. */
int eid; /* Environment id. */
int master_id; /* ID of the master site. */
u_int32_t egen; /* Replication election generation. */
u_int32_t gen; /* Replication generation number. */
u_int32_t recover_gen; /* Last generation number in log. */
int asites; /* Space allocated for sites. */
int nsites; /* Number of sites in group. */
int nvotes; /* Number of votes needed. */
int priority; /* My priority in an election. */
u_int32_t gbytes; /* Limit on data sent in single... */
u_int32_t bytes; /* __rep_process_message call. */
#define DB_REP_REQUEST_GAP 4
#define DB_REP_MAX_GAP 128
u_int32_t request_gap; /* # of records to receive before we
* request a missing log record. */
u_int32_t max_gap; /* Maximum number of records before
* requesting a missing log record. */
/* Status change information */
int elect_th; /* A thread is in rep_elect. */
u_int32_t msg_th; /* Number of callers in rep_proc_msg. */
int start_th; /* A thread is in rep_start. */
u_int32_t handle_cnt; /* Count of handles in library. */
u_int32_t op_cnt; /* Multi-step operation count.*/
int in_recovery; /* Running recovery now. */
/* Backup information. */
int nfiles; /* Number of files we have info on. */
int curfile; /* Current file we're getting. */
__rep_fileinfo_args *curinfo; /* Current file info ptr. */
void *finfo; /* Current file info buffer. */
void *nextinfo; /* Next file info buffer. */
void *originfo; /* Original file info buffer. */
DB_LSN first_lsn; /* Earliest LSN we need. */
DB_LSN last_lsn; /* Latest LSN we need. */
db_pgno_t ready_pg; /* Next pg expected. */
db_pgno_t waiting_pg; /* First pg after gap. */
db_pgno_t max_wait_pg; /* Maximum pg requested. */
u_int32_t npages; /* Num of pages rcvd for this file. */
DB_MPOOLFILE *file_mpf; /* Mpoolfile for in-mem database. */
DB *file_dbp; /* This file's page info. */
DB *queue_dbp; /* Dbp for a queue file. */
/* Vote tallying information. */
int sites; /* Sites heard from. */
int winner; /* Current winner. */
int w_priority; /* Winner priority. */
u_int32_t w_gen; /* Winner generation. */
DB_LSN w_lsn; /* Winner LSN. */
u_int32_t w_tiebreaker; /* Winner tiebreaking value. */
int votes; /* Number of votes for this site. */
/* Statistics. */
DB_REP_STAT stat;
#define REP_F_CLIENT 0x00001 /* Client replica. */
#define REP_F_EPHASE1 0x00002 /* In phase 1 of election. */
#define REP_F_EPHASE2 0x00004 /* In phase 2 of election. */
#define REP_F_MASTER 0x00008 /* Master replica. */
#define REP_F_MASTERELECT 0x00010 /* Master elect */
#define REP_F_NOARCHIVE 0x00020 /* Rep blocks log_archive */
#define REP_F_READY 0x00040 /* Wait for txn_cnt to be 0. */
#define REP_F_RECOVER_LOG 0x00080 /* In recovery - log. */
#define REP_F_RECOVER_PAGE 0x00100 /* In recovery - pages. */
#define REP_F_RECOVER_UPDATE 0x00200 /* In recovery - files. */
#define REP_F_RECOVER_VERIFY 0x00400 /* In recovery - verify. */
#define REP_F_TALLY 0x00800 /* Tallied vote before elect. */
u_int32_t flags;
} REP;
/*
* Recovery flag mask to easily check any/all recovery bits. That is
* REP_F_READY and all REP_F_RECOVER*. This must change if the values
* of the flags change.
*/
#define REP_F_RECOVER_MASK \
(REP_F_READY | REP_F_RECOVER_LOG | REP_F_RECOVER_PAGE | \
REP_F_RECOVER_UPDATE | REP_F_RECOVER_VERIFY)
#define IN_ELECTION(R) F_ISSET((R), REP_F_EPHASE1 | REP_F_EPHASE2)
#define IN_ELECTION_TALLY(R) \
F_ISSET((R), REP_F_EPHASE1 | REP_F_EPHASE2 | REP_F_TALLY)
#define IS_REP_MASTER(dbenv) \
(REP_ON(dbenv) && ((DB_REP *)(dbenv)->rep_handle)->region && \
F_ISSET(((REP *)((DB_REP *)(dbenv)->rep_handle)->region), \
REP_F_MASTER))
#define IS_REP_CLIENT(dbenv) \
(REP_ON(dbenv) && ((DB_REP *)(dbenv)->rep_handle)->region && \
F_ISSET(((REP *)((DB_REP *)(dbenv)->rep_handle)->region), \
REP_F_CLIENT))
#define IS_CLIENT_PGRECOVER(dbenv) \
(IS_REP_CLIENT(dbenv) && \
F_ISSET(((REP *)((DB_REP *)(dbenv)->rep_handle)->region), \
REP_F_RECOVER_PAGE))
/*
* Macros to figure out if we need to do replication pre/post-amble
* processing.
*/
#define IS_REPLICATED(E, D) \
(!F_ISSET((D), DB_AM_RECOVER | DB_AM_REPLICATION) && \
REP_ON(E) && ((DB_REP *)((E)->rep_handle))->region != NULL && \
((DB_REP *)((E)->rep_handle))->region->flags != 0)
#define IS_ENV_REPLICATED(E) (REP_ON(E) && \
((DB_REP *)((E)->rep_handle))->region != NULL && \
((DB_REP *)((E)->rep_handle))->region->flags != 0)
/*
* Per-process replication structure.
*
* There are 2 mutexes used in replication.
* 1. rep_mutexp - This protects the fields of the rep region above.
* 2. db_mutexp - This protects the per-process flags, and bookkeeping
* database and all of the components that maintain it. Those
* components include the following fields in the log region (see log.h):
* a. ready_lsn
* b. waiting_lsn
* c. verify_lsn
* d. wait_recs
* e. rcvd_recs
* f. max_wait_lsn
* These fields in the log region are NOT protected by the log
* region lock at all.
*
* Note that the per-process flags should truly be protected by a
* special per-process thread mutex, but it is currently set in so
* isolated a manner that it didn't make sense to do so and in most
* case we're already holding the db_mutexp anyway.
*
* The lock ordering protocol is that db_mutexp must be acquired
* first and then either rep_mutexp, or the log region mutex may
* be acquired if necessary.
*/
struct __db_rep {
DB_MUTEX *rep_mutexp; /* Mutex for rep region */
DB_MUTEX *db_mutexp; /* Mutex for bookkeeping database. */
DB *rep_db; /* Bookkeeping database. */
REP *region; /* In memory structure. */
#define DBREP_OPENFILES 0x0001 /* This handle has opened files. */
u_int32_t flags; /* per-process flags. */
};
/*
* Control structure for replication communication infrastructure.
*
* Note that the version information should be at the beginning of the
* structure, so that we can rearrange the rest of it while letting the
* version checks continue to work. DB_REPVERSION should be revved any time
* the rest of the structure changes or when the message numbers change.
*/
typedef struct __rep_control {
#define DB_REPVERSION 2
u_int32_t rep_version; /* Replication version number. */
u_int32_t log_version; /* Log version number. */
DB_LSN lsn; /* Log sequence number. */
u_int32_t rectype; /* Message type. */
u_int32_t gen; /* Generation number. */
u_int32_t flags; /* log_put flag value. */
} REP_CONTROL;
/* Election vote information. */
typedef struct __rep_vote {
u_int32_t egen; /* Election generation. */
int nsites; /* Number of sites I've been in
* communication with. */
int nvotes; /* Number of votes needed to win. */
int priority; /* My site's priority. */
u_int32_t tiebreaker; /* Tie-breaking quasi-random value. */
} REP_VOTE_INFO;
typedef struct __rep_vtally {
u_int32_t egen; /* Voter's election generation. */
int eid; /* Voter's ID. */
} REP_VTALLY;
/*
* This structure takes care of representing a transaction.
* It holds all the records, sorted by page number so that
* we can obtain locks and apply updates in a deadlock free
* order.
*/
typedef struct __lsn_collection {
u_int nlsns;
u_int nalloc;
DB_LSN *array;
} LSN_COLLECTION;
/*
* This is used by the page-prep routines to do the lock_vec call to
* apply the updates for a single transaction or a collection of
* transactions.
*/
typedef struct _linfo {
int n;
DB_LOCKREQ *reqs;
DBT *objs;
} linfo_t;
#include "dbinc_auto/rep_ext.h"
#endif /* !_REP_H_ */