db/pg_probackup
db/pg_probackup
1
0
Fork 0
mirror of https://github.com/postgrespro/pg_probackup.git synced 2024-12-05 11:00:22 +02:00
Code Issues Releases Activity
a1eeef782e
pg_probackup/src/backup.c

2691 lines
70 KiB
C
Raw Blame History

/*-------------------------------------------------------------------------
*
* backup.c: backup DB cluster, archived WAL
*
* Portions Copyright (c) 2009-2013, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
* Portions Copyright (c) 2015-2017, Postgres Professional
*
*-------------------------------------------------------------------------
*/
#include "pg_probackup.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <unistd.h>
#include <dirent.h>
#include <time.h>
#include <pthread.h>
#include "libpq/pqsignal.h"
#include "storage/bufpage.h"
#include "catalog/catalog.h"
#include "catalog/pg_tablespace.h"
#include "datapagemap.h"
#include "receivelog.h"
#include "streamutil.h"
#include "pgtar.h"
static int standby_message_timeout = 10 * 1000; /* 10 sec = default */
static XLogRecPtr stop_backup_lsn = InvalidXLogRecPtr;
/*
* How long we should wait for streaming end in seconds.
* Retreived as checkpoint_timeout + checkpoint_timeout * 0.1
*/
static uint32 stream_stop_timeout = 0;
/* Time in which we started to wait for streaming end */
static time_t stream_stop_begin = 0;
const char *progname = "pg_probackup";
/* list of files contained in backup */
static parray *backup_files_list = NULL;
static pthread_mutex_t start_stream_mut = PTHREAD_MUTEX_INITIALIZER;
/*
* We need to wait end of WAL streaming before execute pg_stop_backup().
*/
static pthread_t stream_thread;
static int is_ptrack_enable = false;
/* Backup connections */
static PGconn *backup_conn = NULL;
static PGconn *master_conn = NULL;
static PGconn *backup_conn_replication = NULL;
/* PostgreSQL server version from "backup_conn" */
static int server_version = 0;
static char server_version_str[100] = "";
static bool exclusive_backup = false;
/* Is pg_start_backup() was executed */
static bool backup_in_progress = false;
/* Is pg_stop_backup() was sent */
static bool pg_stop_backup_is_sent = false;
typedef struct
{
const char *from_root;
const char *to_root;
parray *backup_files_list;
parray *prev_backup_filelist;
XLogRecPtr prev_backup_start_lsn;
} backup_files_args;
/*
* Backup routines
*/
static void backup_cleanup(bool fatal, void *userdata);
static void backup_disconnect(bool fatal, void *userdata);
static void backup_files(void *arg);
static void remote_backup_files(void *arg);
static void do_backup_instance(void);
static void pg_start_backup(const char *label, bool smooth, pgBackup *backup);
static void pg_switch_wal(PGconn *conn);
static void pg_stop_backup(pgBackup *backup);
static int checkpoint_timeout(void);
static void parse_backup_filelist_filenames(parray *files, const char *root);
static void write_backup_file_list(parray *files, const char *root);
static void wait_wal_lsn(XLogRecPtr lsn, bool wait_prev_segment);
static void wait_replica_wal_lsn(XLogRecPtr lsn, bool is_start_backup);
static void make_pagemap_from_ptrack(parray *files);
static void StreamLog(void *arg);
static void get_remote_pgdata_filelist(parray *files);
static void ReceiveFileList(parray* files, PGconn *conn, PGresult *res, int rownum);
static void remote_copy_file(PGconn *conn, pgFile* file);
/* Ptrack functions */
static void pg_ptrack_clear(void);
static bool pg_ptrack_support(void);
static bool pg_ptrack_enable(void);
static bool pg_is_in_recovery(void);
static bool pg_archive_enabled(void);
static bool pg_ptrack_get_and_clear_db(Oid dbOid, Oid tblspcOid);
static char *pg_ptrack_get_and_clear(Oid tablespace_oid,
Oid db_oid,
Oid rel_oid,
size_t *result_size);
static XLogRecPtr get_last_ptrack_lsn(void);
/* Check functions */
static void check_server_version(void);
static void check_system_identifiers(void);
static void confirm_block_size(const char *name, int blcksz);
static void set_cfs_datafiles(parray *files, const char *root, char *relative, size_t i);
#define disconnect_and_exit(code) \
{ \
if (conn != NULL) PQfinish(conn); \
exit(code); \
}
/* Fill "files" with data about all the files to backup */
static void
get_remote_pgdata_filelist(parray *files)
{
PGresult *res;
int resultStatus;
int i;
backup_conn_replication = pgut_connect_replication(pgut_dbname);
if (PQsendQuery(backup_conn_replication, "FILE_BACKUP FILELIST") == 0)
elog(ERROR,"%s: could not send replication command \"%s\": %s",
PROGRAM_NAME, "FILE_BACKUP", PQerrorMessage(backup_conn_replication));
res = PQgetResult(backup_conn_replication);
if (PQresultStatus(res) != PGRES_TUPLES_OK)
{
resultStatus = PQresultStatus(res);
PQclear(res);
elog(ERROR, "cannot start getting FILE_BACKUP filelist: %s, result_status %d",
PQerrorMessage(backup_conn_replication), resultStatus);
}
if (PQntuples(res) < 1)
elog(ERROR, "%s: no data returned from server", PROGRAM_NAME);
for (i = 0; i < PQntuples(res); i++)
{
ReceiveFileList(files, backup_conn_replication, res, i);
}
res = PQgetResult(backup_conn_replication);
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
elog(ERROR, "%s: final receive failed: %s",
PROGRAM_NAME, PQerrorMessage(backup_conn_replication));
}
PQfinish(backup_conn_replication);
}
/*
* workhorse for get_remote_pgdata_filelist().
* Parse received message into pgFile structure.
*/
static void
ReceiveFileList(parray* files, PGconn *conn, PGresult *res, int rownum)
{
char filename[MAXPGPATH];
pgoff_t current_len_left = 0;
bool basetablespace;
char *copybuf = NULL;
pgFile *pgfile;
/* What for do we need this basetablespace field?? */
basetablespace = PQgetisnull(res, rownum, 0);
if (basetablespace)
elog(LOG,"basetablespace");
else
elog(LOG, "basetablespace %s", PQgetvalue(res, rownum, 1));
res = PQgetResult(conn);
if (PQresultStatus(res) != PGRES_COPY_OUT)
elog(ERROR, "Could not get COPY data stream: %s", PQerrorMessage(conn));
while (1)
{
int r;
int filemode;
if (copybuf != NULL)
{
PQfreemem(copybuf);
copybuf = NULL;
}
r = PQgetCopyData(conn, &copybuf, 0);
if (r == -2)
elog(ERROR, "Could not read COPY data: %s", PQerrorMessage(conn));
/* end of copy */
if (r == -1)
break;
/* This must be the header for a new file */
if (r != 512)
elog(ERROR, "Invalid tar block header size: %d\n", r);
current_len_left = read_tar_number(&copybuf[124], 12);
/* Set permissions on the file */
filemode = read_tar_number(&copybuf[100], 8);
/* First part of header is zero terminated filename */
snprintf(filename, sizeof(filename), "%s", copybuf);
pgfile = pgFileInit(filename);
pgfile->size = current_len_left;
pgfile->mode |= filemode;
if (filename[strlen(filename) - 1] == '/')
{
/* Symbolic link or directory has size zero */
Assert (pgfile->size == 0);
/* Ends in a slash means directory or symlink to directory */
if (copybuf[156] == '5')
{
/* Directory */
pgfile->mode |= S_IFDIR;
}
else if (copybuf[156] == '2')
{
/* Symlink */
pgfile->mode |= S_IFLNK;
}
else
elog(ERROR, "Unrecognized link indicator \"%c\"\n",
copybuf[156]);
}
else
{
/* regular file */
pgfile->mode |= S_IFREG;
}
parray_append(files, pgfile);
}
if (copybuf != NULL)
PQfreemem(copybuf);
}
/* read one file via replication protocol
* and write it to the destination subdir in 'backup_path' */
static void remote_copy_file(PGconn *conn, pgFile* file)
{
PGresult *res;
char *copybuf = NULL;
char buf[32768];
FILE *out;
char database_path[MAXPGPATH];
char to_path[MAXPGPATH];
bool skip_padding = false;
pgBackupGetPath(&current, database_path, lengthof(database_path),
DATABASE_DIR);
join_path_components(to_path, database_path, file->path);
out = fopen(to_path, "w");
if (out == NULL)
{
int errno_tmp = errno;
elog(ERROR, "cannot open destination file \"%s\": %s",
to_path, strerror(errno_tmp));
}
INIT_CRC32C(file->crc);
/* read from stream and write to backup file */
while (1)
{
int row_length;
int errno_tmp;
int write_buffer_size = 0;
if (copybuf != NULL)
{
PQfreemem(copybuf);
copybuf = NULL;
}
row_length = PQgetCopyData(conn, &copybuf, 0);
if (row_length == -2)
elog(ERROR, "Could not read COPY data: %s", PQerrorMessage(conn));
if (row_length == -1)
break;
if (!skip_padding)
{
write_buffer_size = Min(row_length, sizeof(buf));
memcpy(buf, copybuf, write_buffer_size);
COMP_CRC32C(file->crc, &buf, write_buffer_size);
/* TODO calc checksum*/
if (fwrite(buf, 1, write_buffer_size, out) != write_buffer_size)
{
errno_tmp = errno;
/* oops */
FIN_CRC32C(file->crc);
fclose(out);
PQfinish(conn);
elog(ERROR, "cannot write to \"%s\": %s", to_path,
strerror(errno_tmp));
}
file->read_size += write_buffer_size;
}
if (file->read_size >= file->size)
{
skip_padding = true;
}
}
res = PQgetResult(conn);
/* File is not found. That's normal. */
if (PQresultStatus(res) != PGRES_COMMAND_OK)
{
elog(ERROR, "final receive failed: status %d ; %s",PQresultStatus(res), PQerrorMessage(conn));
}
file->write_size = file->read_size;
FIN_CRC32C(file->crc);
fclose(out);
}
/*
* Take a remote backup of the PGDATA at a file level.
* Copy all directories and files listed in backup_files_list.
*/
static void
remote_backup_files(void *arg)
{
int i;
backup_files_args *arguments = (backup_files_args *) arg;
int n_backup_files_list = parray_num(arguments->backup_files_list);
PGconn *file_backup_conn = NULL;
for (i = 0; i < n_backup_files_list; i++)
{
char *query_str;
PGresult *res;
char *copybuf = NULL;
pgFile *file;
int row_length;
file = (pgFile *) parray_get(arguments->backup_files_list, i);
/* We have already copied all directories */
if (S_ISDIR(file->mode))
continue;
if (__sync_lock_test_and_set(&file->lock, 1) != 0)
continue;
file_backup_conn = pgut_connect_replication(pgut_dbname);
/* check for interrupt */
if (interrupted)
elog(ERROR, "interrupted during backup");
query_str = psprintf("FILE_BACKUP FILEPATH '%s'",file->path);
if (PQsendQuery(file_backup_conn, query_str) == 0)
elog(ERROR,"%s: could not send replication command \"%s\": %s",
PROGRAM_NAME, query_str, PQerrorMessage(file_backup_conn));
res = PQgetResult(file_backup_conn);
/* File is not found. That's normal. */
if (PQresultStatus(res) == PGRES_COMMAND_OK)
{
PQclear(res);
PQfinish(file_backup_conn);
continue;
}
if (PQresultStatus(res) != PGRES_COPY_OUT)
{
PQclear(res);
PQfinish(file_backup_conn);
elog(ERROR, "Could not get COPY data stream: %s", PQerrorMessage(file_backup_conn));
}
/* read the header of the file */
row_length = PQgetCopyData(file_backup_conn, &copybuf, 0);
if (row_length == -2)
elog(ERROR, "Could not read COPY data: %s", PQerrorMessage(file_backup_conn));
/* end of copy TODO handle it */
if (row_length == -1)
elog(ERROR, "Unexpected end of COPY data");
if(row_length != 512)
elog(ERROR, "Invalid tar block header size: %d\n", row_length);
file->size = read_tar_number(&copybuf[124], 12);
/* receive the data from stream and write to backup file */
remote_copy_file(file_backup_conn, file);
elog(LOG, "File \"%s\". Copied %lu bytes",
file->path, (unsigned long) file->write_size);
PQfinish(file_backup_conn);
}
}
/*
* Take a backup of a single postgresql instance.
* Move files from 'pgdata' to a subdirectory in 'backup_path'.
*/
static void
do_backup_instance(void)
{
int i;
char database_path[MAXPGPATH];
char dst_backup_path[MAXPGPATH];
char label[1024];
XLogRecPtr prev_backup_start_lsn = InvalidXLogRecPtr;
pthread_t backup_threads[num_threads];
backup_files_args *backup_threads_args[num_threads];
pgBackup *prev_backup = NULL;
char prev_backup_filelist_path[MAXPGPATH];
parray *prev_backup_filelist = NULL;
elog(LOG, "Database backup start");
/* Initialize size summary */
current.data_bytes = 0;
/* Obtain current timeline */
if (is_remote_backup)
{
char *sysidentifier;
TimeLineID starttli;
XLogRecPtr startpos;
backup_conn_replication = pgut_connect_replication(pgut_dbname);
/* Check replication prorocol connection */
if (!RunIdentifySystem(backup_conn_replication, &sysidentifier, &starttli, &startpos, NULL))
elog(ERROR, "Failed to send command for remote backup");
// TODO implement the check
// if (&sysidentifier != system_identifier)
// elog(ERROR, "Backup data directory was initialized for system id %ld, but target backup directory system id is %ld",
// system_identifier, sysidentifier);
current.tli = starttli;
PQfinish(backup_conn_replication);
}
else
current.tli = get_current_timeline(false);
/*
* In incremental backup mode ensure that already-validated
* backup on current timeline exists and get its filelist.
*/
if (current.backup_mode == BACKUP_MODE_DIFF_PAGE ||
current.backup_mode == BACKUP_MODE_DIFF_PTRACK)
{
parray *backup_list;
/* get list of backups already taken */
backup_list = catalog_get_backup_list(INVALID_BACKUP_ID);
if (backup_list == NULL)
elog(ERROR, "Failed to get backup list.");
prev_backup = catalog_get_last_data_backup(backup_list, current.tli);
if (prev_backup == NULL)
elog(ERROR, "Valid backup on current timeline is not found. "
"Create new FULL backup before an incremental one.");
parray_free(backup_list);
pgBackupGetPath(prev_backup, prev_backup_filelist_path, lengthof(prev_backup_filelist_path),
DATABASE_FILE_LIST);
prev_backup_filelist = dir_read_file_list(pgdata, prev_backup_filelist_path);
/* If lsn is not NULL, only pages with higher lsn will be copied. */
prev_backup_start_lsn = prev_backup->start_lsn;
current.parent_backup = prev_backup->start_time;
pgBackupWriteBackupControlFile(&current);
}
/* Clear ptrack files for FULL and PAGE backup */
if (current.backup_mode != BACKUP_MODE_DIFF_PTRACK && is_ptrack_enable)
pg_ptrack_clear();
/* notify start of backup to PostgreSQL server */
time2iso(label, lengthof(label), current.start_time);
strncat(label, " with pg_probackup", lengthof(label));
pg_start_backup(label, smooth_checkpoint, &current);
/*
* If backup_label does not exist in $PGDATA, stop taking backup.
* NOTE. We can check it only on master, though.
*/
if (exclusive_backup)
{
char label_path[MAXPGPATH];
join_path_components(label_path, pgdata, PG_BACKUP_LABEL_FILE);
/* Leave if no backup file */
if (!fileExists(label_path))
{
elog(LOG, "%s does not exist, stopping backup", PG_BACKUP_LABEL_FILE);
pg_stop_backup(NULL);
elog(ERROR, "%s does not exist in PGDATA", PG_BACKUP_LABEL_FILE);
}
}
pgBackupGetPath(&current, database_path, lengthof(database_path),
DATABASE_DIR);
/* start stream replication */
if (stream_wal)
{
join_path_components(dst_backup_path, database_path, PG_XLOG_DIR);
dir_create_dir(dst_backup_path, DIR_PERMISSION);
pthread_mutex_lock(&start_stream_mut);
pthread_create(&stream_thread, NULL, (void *(*)(void *)) StreamLog, dst_backup_path);
pthread_mutex_lock(&start_stream_mut);
if (conn == NULL)
elog(ERROR, "Cannot continue backup because stream connect has failed.");
pthread_mutex_unlock(&start_stream_mut);
}
/* initialize backup list */
backup_files_list = parray_new();
/* list files with the logical path. omit $PGDATA */
if (is_remote_backup)
get_remote_pgdata_filelist(backup_files_list);
else
dir_list_file(backup_files_list, pgdata, true, true, false);
/* Extract information about files in backup_list parsing their names:*/
parse_backup_filelist_filenames(backup_files_list, pgdata);
if (current.backup_mode != BACKUP_MODE_FULL)
{
elog(LOG, "current_tli:%X", current.tli);
elog(LOG, "prev_backup->start_lsn: %X/%X",
(uint32) (prev_backup->start_lsn >> 32), (uint32) (prev_backup->start_lsn));
elog(LOG, "current.start_lsn: %X/%X",
(uint32) (current.start_lsn >> 32), (uint32) (current.start_lsn));
}
/*
* Build page mapping in incremental mode.
*/
if (current.backup_mode == BACKUP_MODE_DIFF_PAGE)
{
/*
* Build the page map. Obtain information about changed pages
* reading WAL segments present in archives up to the point
* where this backup has started.
*/
extractPageMap(arclog_path, prev_backup->start_lsn, current.tli,
current.start_lsn,
/*
* For backup from master wait for previous segment.
* For backup from replica wait for current segment.
*/
!from_replica);
}
if (current.backup_mode == BACKUP_MODE_DIFF_PTRACK)
{
XLogRecPtr ptrack_lsn = get_last_ptrack_lsn();
if (ptrack_lsn > prev_backup->stop_lsn || ptrack_lsn == InvalidXLogRecPtr)
{
elog(ERROR, "LSN from ptrack_control %lx differs from STOP LSN of previous backup %lx.\n"
"Create new full backup before an incremental one.",
ptrack_lsn, prev_backup->stop_lsn);
}
parray_qsort(backup_files_list, pgFileComparePath);
make_pagemap_from_ptrack(backup_files_list);
}
/*
* Sort pathname ascending. It is necessary to create intermediate
* directories sequentially.
*
* For example:
* 1 - create 'base'
* 2 - create 'base/1'
*/
parray_qsort(backup_files_list, pgFileComparePath);
/*
* Make directories before backup
* and setup threads at the same time
*/
for (i = 0; i < parray_num(backup_files_list); i++)
{
pgFile *file = (pgFile *) parray_get(backup_files_list, i);
/* if the entry was a directory, create it in the backup */
if (S_ISDIR(file->mode))
{
char dirpath[MAXPGPATH];
char *dir_name;
char database_path[MAXPGPATH];
if (!is_remote_backup)
dir_name = GetRelativePath(file->path, pgdata);
else
dir_name = file->path;
elog(LOG, "Create directory \"%s\"", dir_name);
pgBackupGetPath(&current, database_path, lengthof(database_path),
DATABASE_DIR);
join_path_components(dirpath, database_path, dir_name);
dir_create_dir(dirpath, DIR_PERMISSION);
}
/* setup threads */
__sync_lock_release(&file->lock);
}
/* sort by size for load balancing */
parray_qsort(backup_files_list, pgFileCompareSize);
/* init thread args with own file lists */
for (i = 0; i < num_threads; i++)
{
backup_files_args *arg = pg_malloc(sizeof(backup_files_args));
arg->from_root = pgdata;
arg->to_root = database_path;
arg->backup_files_list = backup_files_list;
arg->prev_backup_filelist = prev_backup_filelist;
arg->prev_backup_start_lsn = prev_backup_start_lsn;
backup_threads_args[i] = arg;
}
/* Run threads */
for (i = 0; i < num_threads; i++)
{
elog(LOG, "Start thread num:%i", i);
if (!is_remote_backup)
pthread_create(&backup_threads[i], NULL,
(void *(*)(void *)) backup_files,
backup_threads_args[i]);
else
pthread_create(&backup_threads[i], NULL,
(void *(*)(void *)) remote_backup_files,
backup_threads_args[i]);
}
/* Wait threads */
for (i = 0; i < num_threads; i++)
{
pthread_join(backup_threads[i], NULL);
pg_free(backup_threads_args[i]);
}
/* clean previous backup file list */
if (prev_backup_filelist)
{
parray_walk(prev_backup_filelist, pgFileFree);
parray_free(prev_backup_filelist);
}
/* Notify end of backup */
pg_stop_backup(&current);
/* Add archived xlog files into the list of files of this backup */
if (stream_wal)
{
parray *xlog_files_list;
char pg_xlog_path[MAXPGPATH];
/* Scan backup PG_XLOG_DIR */
xlog_files_list = parray_new();
join_path_components(pg_xlog_path, database_path, PG_XLOG_DIR);
dir_list_file(xlog_files_list, pg_xlog_path, false, true, false);
for (i = 0; i < parray_num(xlog_files_list); i++)
{
pgFile *file = (pgFile *) parray_get(xlog_files_list, i);
if (S_ISREG(file->mode))
calc_file_checksum(file);
/* Remove file path root prefix*/
if (strstr(file->path, database_path) == file->path)
{
char *ptr = file->path;
file->path = pstrdup(GetRelativePath(ptr, database_path));
free(ptr);
}
}
/* Add xlog files into the list of backed up files */
parray_concat(backup_files_list, xlog_files_list);
parray_free(xlog_files_list);
}
/* Print the list of files to backup catalog */
write_backup_file_list(backup_files_list, pgdata);
/* Compute summary of size of regular files in the backup */
for (i = 0; i < parray_num(backup_files_list); i++)
{
pgFile *file = (pgFile *) parray_get(backup_files_list, i);
if (S_ISDIR(file->mode))
current.data_bytes += 4096;
/* Count the amount of the data actually copied */
if (S_ISREG(file->mode))
current.data_bytes += file->write_size;
}
parray_walk(backup_files_list, pgFileFree);
parray_free(backup_files_list);
backup_files_list = NULL;
}
/*
* Entry point of pg_probackup BACKUP subcommand.
*/
int
do_backup(time_t start_time)
{
bool is_ptrack_support;
/* PGDATA and BACKUP_MODE are always required */
if (pgdata == NULL)
elog(ERROR, "required parameter not specified: PGDATA "
"(-D, --pgdata)");
if (current.backup_mode == BACKUP_MODE_INVALID)
elog(ERROR, "required parameter not specified: BACKUP_MODE "
"(-b, --backup-mode)");
/* Create connection for PostgreSQL */
backup_conn = pgut_connect(pgut_dbname);
pgut_atexit_push(backup_disconnect, NULL);
/* Confirm data block size and xlog block size are compatible */
confirm_block_size("block_size", BLCKSZ);
confirm_block_size("wal_block_size", XLOG_BLCKSZ);
from_replica = pg_is_in_recovery();
/* Confirm that this server version is supported */
check_server_version();
/* TODO fix it for remote backup*/
if (!is_remote_backup)
current.checksum_version = get_data_checksum_version(true);
StrNCpy(current.server_version, server_version_str,
sizeof(current.server_version));
current.stream = stream_wal;
is_ptrack_support = pg_ptrack_support();
if (is_ptrack_support)
{
is_ptrack_enable = pg_ptrack_enable();
}
if (current.backup_mode == BACKUP_MODE_DIFF_PTRACK)
{
if (!is_ptrack_support)
elog(ERROR, "This PostgreSQL instance does not support ptrack");
else
{
if(!is_ptrack_enable)
elog(ERROR, "Ptrack is disabled");
}
}
/* archiving check */
if (!current.stream && !pg_archive_enabled())
elog(ERROR, "Archiving must be enabled for archive backup");
if (current.backup_mode == BACKUP_MODE_DIFF_PAGE && !pg_archive_enabled())
elog(ERROR, "Archiving must be enabled for PAGE backup");
if (from_replica)
{
/* Check master connection options */
if (master_host == NULL)
elog(ERROR, "Options for connection to master must be provided to perform backup from replica");
/* Create connection to master server */
master_conn = pgut_connect_extended(master_host, master_port, master_db, master_user);
}
/* Get exclusive lock of backup catalog */
catalog_lock();
/*
* Ensure that backup directory was initialized for the same PostgreSQL
* instance we opened connection to. And that target backup database PGDATA
* belogns to the same instance.
*/
/* TODO fix it for remote backup */
if (!is_remote_backup)
check_system_identifiers();
elog(LOG, "Backup start. backup-mode = %s, stream = %s, remote = %s",
pgBackupGetBackupMode(&current), current.stream ? "true" : "false",
is_remote_backup ? "true" : "false");
/* Start backup. Update backup status. */
current.status = BACKUP_STATUS_RUNNING;
current.start_time = start_time;
/* Create backup directory and BACKUP_CONTROL_FILE */
if (pgBackupCreateDir(&current))
elog(ERROR, "cannot create backup directory");
pgBackupWriteBackupControlFile(&current);
elog(LOG, "Backup destination is initialized");
/* set the error processing function for the backup process */
pgut_atexit_push(backup_cleanup, NULL);
/* backup data */
do_backup_instance();
pgut_atexit_pop(backup_cleanup, NULL);
/* compute size of wal files of this backup stored in the archive */
if (!current.stream)
{
current.wal_bytes = XLOG_SEG_SIZE *
(current.stop_lsn/XLogSegSize - current.start_lsn/XLogSegSize + 1);
}
/* Backup is done. Update backup status */
current.end_time = time(NULL);
current.status = BACKUP_STATUS_DONE;
pgBackupWriteBackupControlFile(&current);
elog(LOG, "Backup completed. Total bytes : " INT64_FORMAT "",
current.data_bytes);
pgBackupValidate(&current);
elog(INFO, "Backup %s completed", base36enc(current.start_time));
/*
* After successfil backup completion remove backups
* which are expired according to retention policies
*/
if (delete_expired)
do_retention_purge();
return 0;
}
/*
* Confirm that this server version is supported
*/
static void
check_server_version(void)
{
PGresult *res;
/* confirm server version */
server_version = PQserverVersion(backup_conn);
if (server_version < 90500)
elog(ERROR,
"server version is %d.%d.%d, must be %s or higher",
server_version / 10000,
(server_version / 100) % 100,
server_version % 100, "9.5");
if (from_replica && server_version < 90600)
elog(ERROR,
"server version is %d.%d.%d, must be %s or higher for backup from replica",
server_version / 10000,
(server_version / 100) % 100,
server_version % 100, "9.6");
/* Do exclusive backup only for PostgreSQL 9.5 */
exclusive_backup = server_version < 90600;
/* Save server_version to use it in future */
res = pgut_execute(backup_conn, "show server_version", 0, NULL);
StrNCpy(server_version_str, PQgetvalue(res, 0, 0), sizeof(server_version_str));
PQclear(res);
}
/*
* Ensure that backup directory was initialized for the same PostgreSQL
* instance we opened connection to. And that target backup database PGDATA
* belogns to the same instance.
* All system identifiers must be equal.
*/
static void
check_system_identifiers(void)
{
PGresult *res;
uint64 system_id_conn;
uint64 system_id_pgdata;
char *val;
system_id_pgdata = get_system_identifier(pgdata);
res = pgut_execute(backup_conn,
"SELECT system_identifier FROM pg_control_system()",
0, NULL);
val = PQgetvalue(res, 0, 0);
if (!parse_uint64(val, &system_id_conn, 0))
{
PQclear(res);
elog(ERROR, "%s is not system_identifier", val);
}
PQclear(res);
if (system_id_conn != system_identifier)
elog(ERROR, "Backup data directory was initialized for system id %ld, but connected instance system id is %ld",
system_identifier, system_id_conn);
if (system_id_pgdata != system_identifier)
elog(ERROR, "Backup data directory was initialized for system id %ld, but target backup directory system id is %ld",
system_identifier, system_id_pgdata);
}
/*
* Ensure that target backup database is initialized with
* compatible settings. Currently check BLCKSZ and XLOG_BLCKSZ.
*/
static void
confirm_block_size(const char *name, int blcksz)
{
PGresult *res;
char *endp;
int block_size;
res = pgut_execute(backup_conn, "SELECT current_setting($1)", 1, &name);
if (PQntuples(res) != 1 || PQnfields(res) != 1)
elog(ERROR, "cannot get %s: %s", name, PQerrorMessage(backup_conn));
block_size = strtol(PQgetvalue(res, 0, 0), &endp, 10);
PQclear(res);
if ((endp && *endp) || block_size != blcksz)
elog(ERROR,
"%s(%d) is not compatible(%d expected)",
name, block_size, blcksz);
}
/*
* Notify start of backup to PostgreSQL server.
*/
static void
pg_start_backup(const char *label, bool smooth, pgBackup *backup)
{
PGresult *res;
const char *params[2];
uint32 xlogid;
uint32 xrecoff;
PGconn *conn;
params[0] = label;
/* For replica we call pg_start_backup() on master */
conn = (from_replica) ? master_conn : backup_conn;
/* 2nd argument is 'fast'*/
params[1] = smooth ? "false" : "true";
if (!exclusive_backup)
res = pgut_execute(conn,
"SELECT pg_start_backup($1, $2, false)",
2,
params);
else
res = pgut_execute(conn,
"SELECT pg_start_backup($1, $2)",
2,
params);
/* Extract timeline and LSN from results of pg_start_backup() */
XLogDataFromLSN(PQgetvalue(res, 0, 0), &xlogid, &xrecoff);
/* Calculate LSN */
backup->start_lsn = (XLogRecPtr) ((uint64) xlogid << 32) | xrecoff;
PQclear(res);
if (current.backup_mode == BACKUP_MODE_DIFF_PAGE)
/*
* Switch to a new WAL segment. It is necessary to get archived WAL
* segment, which includes start LSN of current backup.
*/
pg_switch_wal(conn);
if (!stream_wal)
{
/*
* Do not wait start_lsn for stream backup.
* Because WAL streaming will start after pg_start_backup() in stream
* mode.
*/
/* In PAGE mode wait for current segment... */
if (current.backup_mode == BACKUP_MODE_DIFF_PAGE)
wait_wal_lsn(backup->start_lsn, false);
/* ...for others wait for previous segment */
else
wait_wal_lsn(backup->start_lsn, true);
}
/* Wait for start_lsn to be replayed by replica */
if (from_replica)
wait_replica_wal_lsn(backup->start_lsn, true);
/*
* Set flag that pg_start_backup() was called. If an error will happen it
* is necessary to call pg_stop_backup() in backup_cleanup().
*/
backup_in_progress = true;
}
/*
* Switch to a new WAL segment. It should be called only for master.
*/
static void
pg_switch_wal(PGconn *conn)
{
PGresult *res;
/* Remove annoying NOTICE messages generated by backend */
res = pgut_execute(conn, "SET client_min_messages = warning;", 0, NULL);
PQclear(res);
if (server_version >= 100000)
res = pgut_execute(conn, "SELECT * FROM pg_switch_wal()", 0, NULL);
else
res = pgut_execute(conn, "SELECT * FROM pg_switch_xlog()", 0, NULL);
PQclear(res);
}
/*
* Check if the instance supports ptrack
* TODO Maybe we should rather check ptrack_version()?
*/
static bool
pg_ptrack_support(void)
{
PGresult *res_db;
res_db = pgut_execute(backup_conn,
"SELECT proname FROM pg_proc WHERE proname='ptrack_version'",
0, NULL);
if (PQntuples(res_db) == 0)
{
PQclear(res_db);
return false;
}
PQclear(res_db);
res_db = pgut_execute(backup_conn,
"SELECT ptrack_version()",
0, NULL);
if (PQntuples(res_db) == 0)
{
PQclear(res_db);
return false;
}
/* Now we support only ptrack version 1.3 */
if (strcmp(PQgetvalue(res_db, 0, 0), "1.3") != 0)
{
PQclear(res_db);
return false;
}
PQclear(res_db);
return true;
}
/* Check if ptrack is enabled in target instance */
static bool
pg_ptrack_enable(void)
{
PGresult *res_db;
res_db = pgut_execute(backup_conn, "show ptrack_enable", 0, NULL);
if (strcmp(PQgetvalue(res_db, 0, 0), "on") != 0)
{
PQclear(res_db);
return false;
}
PQclear(res_db);
return true;
}
/* Check if target instance is replica */
static bool
pg_is_in_recovery(void)
{
PGresult *res_db;
res_db = pgut_execute(backup_conn, "SELECT pg_is_in_recovery()", 0, NULL);
if (PQgetvalue(res_db, 0, 0)[0] == 't')
{
PQclear(res_db);
return true;
}
PQclear(res_db);
return false;
}
/*
* Check if archiving is enabled
*/
static bool
pg_archive_enabled(void)
{
PGresult *res_db;
res_db = pgut_execute(backup_conn, "show archive_mode", 0, NULL);
if (strcmp(PQgetvalue(res_db, 0, 0), "off") == 0)
{
PQclear(res_db);
return false;
}
PQclear(res_db);
res_db = pgut_execute(backup_conn, "show archive_command", 0, NULL);
if (strlen(PQgetvalue(res_db, 0, 0)) == 0)
{
PQclear(res_db);
return false;
}
PQclear(res_db);
return true;
}
/* Clear ptrack files in all databases of the instance we connected to */
static void
pg_ptrack_clear(void)
{
PGresult *res_db,
*res;
const char *dbname;
int i;
Oid dbOid, tblspcOid;
char *params[2];
params[0] = palloc(64);
params[1] = palloc(64);
res_db = pgut_execute(backup_conn, "SELECT datname, oid, dattablespace FROM pg_database",
0, NULL);
for(i = 0; i < PQntuples(res_db); i++)
{
PGconn *tmp_conn;
dbname = PQgetvalue(res_db, i, 0);
if (strcmp(dbname, "template0") == 0)
continue;
dbOid = atoi(PQgetvalue(res_db, i, 1));
tblspcOid = atoi(PQgetvalue(res_db, i, 2));
tmp_conn = pgut_connect(dbname);
res = pgut_execute(tmp_conn, "SELECT pg_ptrack_clear()", 0, NULL);
sprintf(params[0], "%i", dbOid);
sprintf(params[1], "%i", tblspcOid);
res = pgut_execute(tmp_conn, "SELECT pg_ptrack_get_and_clear_db($1, $2)",
2, (const char **)params);
PQclear(res);
pgut_disconnect(tmp_conn);
}
pfree(params[0]);
pfree(params[1]);
PQclear(res_db);
}
static bool
pg_ptrack_get_and_clear_db(Oid dbOid, Oid tblspcOid)
{
char *params[2];
char *dbname;
PGresult *res_db;
PGresult *res;
char *result;
params[0] = palloc(64);
params[1] = palloc(64);
sprintf(params[0], "%i", dbOid);
res_db = pgut_execute(backup_conn,
"SELECT datname FROM pg_database WHERE oid=$1",
1, (const char **) params);
/*
* If database is not found, it's not an error.
* It could have been deleted since previous backup.
*/
if (PQntuples(res_db) != 1 || PQnfields(res_db) != 1)
return false;
dbname = PQgetvalue(res_db, 0, 0);
/* Always backup all files from template0 database */
if (strcmp(dbname, "template0") == 0)
{
PQclear(res_db);
return true;
}
PQclear(res_db);
sprintf(params[0], "%i", dbOid);
sprintf(params[1], "%i", tblspcOid);
res = pgut_execute(backup_conn, "SELECT pg_ptrack_get_and_clear_db($1, $2)",
2, (const char **)params);
if (PQnfields(res) != 1)
elog(ERROR, "cannot perform pg_ptrack_get_and_clear_db()");
result = PQgetvalue(res, 0, 0);
PQclear(res);
pfree(params[0]);
pfree(params[1]);
return (strcmp(result, "t") == 0);
}
/* Read and clear ptrack files of the target relation.
* Result is a bytea ptrack map of all segments of the target relation.
* case 1: we know a tablespace_oid, db_oid, and rel_filenode
* case 2: we know db_oid and rel_filenode (no tablespace_oid, because file in pg_default)
* case 3: we know only rel_filenode (because file in pg_global)
*/
static char *
pg_ptrack_get_and_clear(Oid tablespace_oid, Oid db_oid, Oid rel_filenode,
size_t *result_size)
{
PGconn *tmp_conn;
PGresult *res_db,
*res;
char *params[2];
char *result;
char *val;
params[0] = palloc(64);
params[1] = palloc(64);
/* regular file (not in directory 'global') */
if (db_oid != 0)
{
char *dbname;
sprintf(params[0], "%i", db_oid);
res_db = pgut_execute(backup_conn,
"SELECT datname FROM pg_database WHERE oid=$1",
1, (const char **) params);
/*
* If database is not found, it's not an error.
* It could have been deleted since previous backup.
*/
if (PQntuples(res_db) != 1 || PQnfields(res_db) != 1)
return NULL;
dbname = PQgetvalue(res_db, 0, 0);
if (strcmp(dbname, "template0") == 0)
{
PQclear(res_db);
return NULL;
}
tmp_conn = pgut_connect(dbname);
sprintf(params[0], "%i", tablespace_oid);
sprintf(params[1], "%i", rel_filenode);
res = pgut_execute(tmp_conn, "SELECT pg_ptrack_get_and_clear($1, $2)",
2, (const char **)params);
if (PQnfields(res) != 1)
elog(ERROR, "cannot get ptrack file from database \"%s\" by tablespace oid %u and relation oid %u",
dbname, tablespace_oid, rel_filenode);
PQclear(res_db);
pgut_disconnect(tmp_conn);
}
/* file in directory 'global' */
else
{
/*
* execute ptrack_get_and_clear for relation in pg_global
* Use backup_conn, cause we can do it from any database.
*/
sprintf(params[0], "%i", tablespace_oid);
sprintf(params[1], "%i", rel_filenode);
res = pgut_execute(backup_conn, "SELECT pg_ptrack_get_and_clear($1, $2)",
2, (const char **)params);
if (PQnfields(res) != 1)
elog(ERROR, "cannot get ptrack file from pg_global tablespace and relation oid %u",
rel_filenode);
}
val = PQgetvalue(res, 0, 0);
/* TODO Now pg_ptrack_get_and_clear() returns bytea ending with \x.
* It should be fixed in future ptrack releases, but till then we
* can parse it.
*/
if (strcmp("x", val+1) == 0)
{
/* Ptrack file is missing */
return NULL;
}
result = (char *) PQunescapeBytea((unsigned char *) PQgetvalue(res, 0, 0),
result_size);
PQclear(res);
pfree(params[0]);
pfree(params[1]);
return result;
}
/*
* Wait for target 'lsn'.
*
* If current backup started in archive mode wait for 'lsn' to be archived in
* archive 'wal' directory with WAL segment file.
* If current backup started in stream mode wait for 'lsn' to be streamed in
* 'pg_wal' directory.
*
* If 'wait_prev_segment' wait for previous segment.
*/
static void
wait_wal_lsn(XLogRecPtr lsn, bool wait_prev_segment)
{
TimeLineID tli;
XLogSegNo targetSegNo;
char wal_dir[MAXPGPATH],
wal_segment_full_path[MAXPGPATH];
char wal_segment[MAXFNAMELEN];
uint32 try_count = 0,
timeout;
tli = get_current_timeline(false);
/* Compute the name of the WAL file containig requested LSN */
XLByteToSeg(lsn, targetSegNo);
if (wait_prev_segment)
targetSegNo--;
XLogFileName(wal_segment, tli, targetSegNo);
if (stream_wal)
{
pgBackupGetPath2(&current, wal_dir, lengthof(wal_dir),
DATABASE_DIR, PG_XLOG_DIR);
join_path_components(wal_segment_full_path, wal_dir, wal_segment);
timeout = (uint32) checkpoint_timeout();
timeout = timeout + timeout * 0.1;
}
else
{
join_path_components(wal_segment_full_path, arclog_path, wal_segment);
timeout = archive_timeout;
}
/* Wait until target LSN is archived or streamed */
while (true)
{
bool file_exists = fileExists(wal_segment_full_path);
if (file_exists)
{
/* Do not check LSN for previous WAL segment */
if (wait_prev_segment)
return;
/*
* A WAL segment found. Check LSN on it.
*/
if ((stream_wal && wal_contains_lsn(wal_dir, lsn, tli)) ||
(!stream_wal && wal_contains_lsn(arclog_path, lsn, tli)))
/* Target LSN was found */
return;
}
sleep(1);
if (interrupted)
elog(ERROR, "interrupted during waiting for WAL archiving");
try_count++;
/* Inform user if WAL segment is absent in first attempt */
if (try_count == 1)
{
if (wait_prev_segment)
elog(INFO, "wait for WAL segment %s to be archived",
wal_segment_full_path);
else
elog(INFO, "wait for LSN %X/%X in archived WAL segment %s",
(uint32) (lsn >> 32), (uint32) lsn, wal_segment_full_path);
}
if (timeout > 0 && try_count > timeout)
{
if (file_exists)
elog(ERROR, "WAL segment %s was archived, "
"but target LSN %X/%X could not be archived in %d seconds",
wal_segment, (uint32) (lsn >> 32), (uint32) lsn, timeout);
/* If WAL segment doesn't exist or we wait for previous segment */
else
elog(ERROR,
"switched WAL segment %s could not be archived in %d seconds",
wal_segment, timeout);
}
}
}
/*
* Wait for target 'lsn' on replica instance from master.
*/
static void
wait_replica_wal_lsn(XLogRecPtr lsn, bool is_start_backup)
{
uint32 try_count = 0;
Assert(from_replica);
while (true)
{
PGresult *res;
uint32 xlogid;
uint32 xrecoff;
XLogRecPtr replica_lsn;
/*
* For lsn from pg_start_backup() we need it to be replayed on replica's
* data.
*/
if (is_start_backup)
{
if (server_version >= 100000)
res = pgut_execute(backup_conn, "SELECT pg_last_wal_replay_lsn()",
0, NULL);
else
res = pgut_execute(backup_conn, "SELECT pg_last_xlog_replay_location()",
0, NULL);
}
/*
* For lsn from pg_stop_backup() we need it only to be received by
* replica and fsync()'ed on WAL segment.
*/
else
{
if (server_version >= 100000)
res = pgut_execute(backup_conn, "SELECT pg_last_wal_receive_lsn()",
0, NULL);
else
res = pgut_execute(backup_conn, "SELECT pg_last_xlog_receive_location()",
0, NULL);
}
/* Extract timeline and LSN from result */
XLogDataFromLSN(PQgetvalue(res, 0, 0), &xlogid, &xrecoff);
/* Calculate LSN */
replica_lsn = (XLogRecPtr) ((uint64) xlogid << 32) | xrecoff;
PQclear(res);
/* target lsn was replicated */
if (replica_lsn >= lsn)
break;
sleep(1);
if (interrupted)
elog(ERROR, "Interrupted during waiting for target LSN");
try_count++;
/* Inform user if target lsn is absent in first attempt */
if (try_count == 1)
elog(INFO, "Wait for target LSN %X/%X to be received by replica",
(uint32) (lsn >> 32), (uint32) lsn);
if (replica_timeout > 0 && try_count > replica_timeout)
elog(ERROR, "Target LSN %X/%X could not be recevied by replica "
"in %d seconds",
(uint32) (lsn >> 32), (uint32) lsn,
replica_timeout);
}
}
/*
* Notify end of backup to PostgreSQL server.
*/
static void
pg_stop_backup(pgBackup *backup)
{
PGconn *conn;
PGresult *res;
uint32 xlogid;
uint32 xrecoff;
XLogRecPtr restore_lsn = InvalidXLogRecPtr;
bool sent = false;
int pg_stop_backup_timeout = 0;
/*
* We will use this values if there are no transactions between start_lsn
* and stop_lsn.
*/
time_t recovery_time;
TransactionId recovery_xid;
if (!backup_in_progress)
elog(FATAL, "backup is not in progress");
/* For replica we call pg_stop_backup() on master */
conn = (from_replica) ? master_conn : backup_conn;
/* Remove annoying NOTICE messages generated by backend */
res = pgut_execute(conn, "SET client_min_messages = warning;",
0, NULL);
PQclear(res);
/* Create restore point */
if (backup != NULL)
{
const char *params[1];
char name[1024];
char *backup_id;
backup_id = base36enc(backup->start_time);
if (!from_replica)
snprintf(name, lengthof(name), "pg_probackup, backup_id %s",
backup_id);
else
snprintf(name, lengthof(name), "pg_probackup, backup_id %s. Replica Backup",
backup_id);
params[0] = name;
res = pgut_execute(conn, "SELECT pg_create_restore_point($1)",
1, params);
PQclear(res);
pfree(backup_id);
}
/*
* send pg_stop_backup asynchronously because we could came
* here from backup_cleanup() after some error caused by
* postgres archive_command problem and in this case we will
* wait for pg_stop_backup() forever.
*/
if (!pg_stop_backup_is_sent)
{
if (!exclusive_backup)
/*
* Stop the non-exclusive backup. Besides stop_lsn it returns from
* pg_stop_backup(false) copy of the backup label and tablespace map
* so they can be written to disk by the caller.
*/
sent = pgut_send(conn,
"SELECT *, txid_snapshot_xmax(txid_current_snapshot()),"
" current_timestamp(0)::timestamptz"
" FROM pg_stop_backup(false)",
0, NULL, WARNING);
else
sent = pgut_send(conn,
"SELECT *, txid_snapshot_xmax(txid_current_snapshot()),"
" current_timestamp(0)::timestamptz"
" FROM pg_stop_backup()",
0, NULL, WARNING);
pg_stop_backup_is_sent = true;
if (!sent)
elog(ERROR, "Failed to send pg_stop_backup query");
}
/*
* Wait for the result of pg_stop_backup(),
* but no longer than PG_STOP_BACKUP_TIMEOUT seconds
*/
if (pg_stop_backup_is_sent && !in_cleanup)
{
while (1)
{
if (!PQconsumeInput(conn) || PQisBusy(conn))
{
pg_stop_backup_timeout++;
sleep(1);
if (interrupted)
{
pgut_cancel(conn);
elog(ERROR, "interrupted during waiting for pg_stop_backup");
}
if (pg_stop_backup_timeout == 1)
elog(INFO, "wait for pg_stop_backup()");
/*
* If postgres haven't answered in PG_STOP_BACKUP_TIMEOUT seconds,
* send an interrupt.
*/
if (pg_stop_backup_timeout > PG_STOP_BACKUP_TIMEOUT)
{
pgut_cancel(conn);
elog(ERROR, "pg_stop_backup doesn't answer in %d seconds, cancel it",
PG_STOP_BACKUP_TIMEOUT);
}
}
else
{
res = PQgetResult(conn);
break;
}
}
if (!res)
elog(ERROR, "pg_stop backup() failed");
}
backup_in_progress = false;
/* If stop_backup was sent and we are here, it means that is was received */
if (pg_stop_backup_is_sent && !in_cleanup)
{
/* Extract timeline and LSN from results of pg_stop_backup() */
XLogDataFromLSN(PQgetvalue(res, 0, 0), &xlogid, &xrecoff);
/* Calculate LSN */
stop_backup_lsn = (XLogRecPtr) ((uint64) xlogid << 32) | xrecoff;
if (!XRecOffIsValid(stop_backup_lsn))
{
stop_backup_lsn = restore_lsn;
}
if (!XRecOffIsValid(stop_backup_lsn))
elog(ERROR, "Invalid stop_backup_lsn value %X/%X",
(uint32) (stop_backup_lsn >> 32), (uint32) (stop_backup_lsn));
/* Write backup_label and tablespace_map for backup from replica */
if (!exclusive_backup)
{
char path[MAXPGPATH];
char backup_label[MAXPGPATH];
FILE *fp;
pgFile *file;
size_t len;
Assert(PQnfields(res) >= 5);
pgBackupGetPath(&current, path, lengthof(path), DATABASE_DIR);
/* Write backup_label */
join_path_components(backup_label, path, PG_BACKUP_LABEL_FILE);
fp = fopen(backup_label, "w");
if (fp == NULL)
elog(ERROR, "can't open backup label file \"%s\": %s",
backup_label, strerror(errno));
len = strlen(PQgetvalue(res, 0, 1));
if (fwrite(PQgetvalue(res, 0, 1), 1, len, fp) != len ||
fflush(fp) != 0 ||
fsync(fileno(fp)) != 0 ||
fclose(fp))
elog(ERROR, "can't write backup label file \"%s\": %s",
backup_label, strerror(errno));
/*
* It's vital to check if backup_files_list is initialized,
* because we could get here because the backup was interrupted
*/
if (backup_files_list)
{
file = pgFileNew(backup_label, true);
calc_file_checksum(file);
free(file->path);
file->path = strdup(PG_BACKUP_LABEL_FILE);
parray_append(backup_files_list, file);
}
/* Write tablespace_map */
if (strlen(PQgetvalue(res, 0, 2)) > 0)
{
char tablespace_map[MAXPGPATH];
join_path_components(tablespace_map, path, PG_TABLESPACE_MAP_FILE);
fp = fopen(tablespace_map, "w");
if (fp == NULL)
elog(ERROR, "can't open tablespace map file \"%s\": %s",
tablespace_map, strerror(errno));
len = strlen(PQgetvalue(res, 0, 2));
if (fwrite(PQgetvalue(res, 0, 2), 1, len, fp) != len ||
fflush(fp) != 0 ||
fsync(fileno(fp)) != 0 ||
fclose(fp))
elog(ERROR, "can't write tablespace map file \"%s\": %s",
tablespace_map, strerror(errno));
if (backup_files_list)
{
file = pgFileNew(tablespace_map, true);
if (S_ISREG(file->mode))
calc_file_checksum(file);
free(file->path);
file->path = strdup(PG_TABLESPACE_MAP_FILE);
parray_append(backup_files_list, file);
}
}
if (sscanf(PQgetvalue(res, 0, 3), XID_FMT, &recovery_xid) != 1)
elog(ERROR,
"result of txid_snapshot_xmax() is invalid: %s",
PQerrorMessage(conn));
if (!parse_time(PQgetvalue(res, 0, 4), &recovery_time))
elog(ERROR,
"result of current_timestamp is invalid: %s",
PQerrorMessage(conn));
}
else
{
if (sscanf(PQgetvalue(res, 0, 1), XID_FMT, &recovery_xid) != 1)
elog(ERROR,
"result of txid_snapshot_xmax() is invalid: %s",
PQerrorMessage(conn));
if (!parse_time(PQgetvalue(res, 0, 2), &recovery_time))
elog(ERROR,
"result of current_timestamp is invalid: %s",
PQerrorMessage(conn));
}
PQclear(res);
if (stream_wal)
/* Wait for the completion of stream */
pthread_join(stream_thread, NULL);
}
/* Fill in fields if that is the correct end of backup. */
if (backup != NULL)
{
char *xlog_path,
stream_xlog_path[MAXPGPATH];
/* Wait for stop_lsn to be received by replica */
if (from_replica)
wait_replica_wal_lsn(stop_backup_lsn, false);
/*
* Wait for stop_lsn to be archived or streamed.
* We wait for stop_lsn in stream mode just in case.
*/
wait_wal_lsn(stop_backup_lsn, false);
if (stream_wal)
{
pgBackupGetPath2(backup, stream_xlog_path,
lengthof(stream_xlog_path),
DATABASE_DIR, PG_XLOG_DIR);
xlog_path = stream_xlog_path;
}
else
xlog_path = arclog_path;
backup->tli = get_current_timeline(false);
backup->stop_lsn = stop_backup_lsn;
if (!read_recovery_info(xlog_path, backup->tli,
backup->start_lsn, backup->stop_lsn,
&backup->recovery_time, &backup->recovery_xid))
{
backup->recovery_time = recovery_time;
backup->recovery_xid = recovery_xid;
}
}
}
/*
* Retreive checkpoint_timeout GUC value in seconds.
*/
static int
checkpoint_timeout(void)
{
PGresult *res;
const char *val;
const char *hintmsg;
int val_int;
res = pgut_execute(backup_conn, "show checkpoint_timeout", 0, NULL);
val = PQgetvalue(res, 0, 0);
if (!parse_int(val, &val_int, OPTION_UNIT_S, &hintmsg))
{
PQclear(res);
if (hintmsg)
elog(ERROR, "Invalid value of checkout_timeout %s: %s", val,
hintmsg);
else
elog(ERROR, "Invalid value of checkout_timeout %s", val);
}
PQclear(res);
return val_int;
}
/*
* Return true if the path is a existing regular file.
*/
bool
fileExists(const char *path)
{
struct stat buf;
if (stat(path, &buf) == -1 && errno == ENOENT)
return false;
else if (!S_ISREG(buf.st_mode))
return false;
else
return true;
}
/*
* Notify end of backup to server when "backup_label" is in the root directory
* of the DB cluster.
* Also update backup status to ERROR when the backup is not finished.
*/
static void
backup_cleanup(bool fatal, void *userdata)
{
/*
* Update status of backup in BACKUP_CONTROL_FILE to ERROR.
* end_time != 0 means backup finished
*/
if (current.status == BACKUP_STATUS_RUNNING && current.end_time == 0)
{
elog(LOG, "Backup is running, update its status to ERROR");
current.end_time = time(NULL);
current.status = BACKUP_STATUS_ERROR;
pgBackupWriteBackupControlFile(&current);
}
/*
* If backup is in progress, notify stop of backup to PostgreSQL
*/
if (backup_in_progress)
{
elog(LOG, "backup in progress, stop backup");
pg_stop_backup(NULL); /* don't care stop_lsn on error case */
}
}
/*
* Disconnect backup connection during quit pg_probackup.
*/
static void
backup_disconnect(bool fatal, void *userdata)
{
pgut_disconnect(backup_conn);
if (master_conn)
pgut_disconnect(master_conn);
}
/*
* Take a backup of the PGDATA at a file level.
* Copy all directories and files listed in backup_files_list.
* If the file is 'datafile' (regular relation's main fork), read it page by page,
* verify checksum and copy.
* In incremental backup mode, copy only files or datafiles' pages changed after
* previous backup.
*/
static void
backup_files(void *arg)
{
int i;
backup_files_args *arguments = (backup_files_args *) arg;
int n_backup_files_list = parray_num(arguments->backup_files_list);
/* backup a file */
for (i = 0; i < n_backup_files_list; i++)
{
int ret;
struct stat buf;
pgFile *file = (pgFile *) parray_get(arguments->backup_files_list, i);
elog(VERBOSE, "Copying file: \"%s\" ", file->path);
if (__sync_lock_test_and_set(&file->lock, 1) != 0)
continue;
/* check for interrupt */
if (interrupted)
elog(ERROR, "interrupted during backup");
if (progress)
elog(LOG, "Progress: (%d/%d). Process file \"%s\"",
i + 1, n_backup_files_list, file->path);
/* stat file to check its current state */
ret = stat(file->path, &buf);
if (ret == -1)
{
if (errno == ENOENT)
{
/*
* If file is not found, this is not en error.
* It could have been deleted by concurrent postgres transaction.
*/
file->write_size = BYTES_INVALID;
elog(LOG, "File \"%s\" is not found", file->path);
continue;
}
else
{
elog(ERROR,
"can't stat file to backup \"%s\": %s",
file->path, strerror(errno));
}
}
/* We have already copied all directories */
if (S_ISDIR(buf.st_mode))
continue;
if (S_ISREG(buf.st_mode))
{
/* copy the file into backup */
if (file->is_datafile && !file->is_cfs)
{
/* backup block by block if datafile AND not compressed by cfs*/
if (!backup_data_file(arguments->from_root,
arguments->to_root, file,
arguments->prev_backup_start_lsn,
current.backup_mode))
{
file->write_size = BYTES_INVALID;
elog(LOG, "File \"%s\" was not copied to backup", file->path);
continue;
}
}
else if (!copy_file(arguments->from_root,
arguments->to_root,
file))
{
file->write_size = BYTES_INVALID;
elog(LOG, "File \"%s\" was not copied to backup", file->path);
continue;
}
elog(LOG, "File \"%s\". Copied %lu bytes",
file->path, (unsigned long) file->write_size);
}
else
elog(LOG, "unexpected file type %d", buf.st_mode);
}
}
/*
* Extract information about files in backup_list parsing their names:
* - remove temp tables from the list
* - remove unlogged tables from the list (leave the _init fork)
* - set flags for database directories
* - set flags for datafiles
*/
static void
parse_backup_filelist_filenames(parray *files, const char *root)
{
size_t i;
Oid unlogged_file_reloid = 0;
for (i = 0; i < parray_num(files); i++)
{
pgFile *file = (pgFile *) parray_get(files, i);
char *relative;
char filename[MAXPGPATH];
int sscanf_result;
relative = GetRelativePath(file->path, root);
filename[0] = '\0';
elog(VERBOSE, "-----------------------------------------------------: %s", relative);
if (path_is_prefix_of_path("global", relative))
{
file->tblspcOid = GLOBALTABLESPACE_OID;
sscanf_result = sscanf(relative, "global/%s", filename);
elog(VERBOSE, "global sscanf result: %i", sscanf_result);
if (strcmp(relative, "global") == 0)
{
Assert(S_ISDIR(file->mode));
elog(VERBOSE, "the global itself, filepath %s", relative);
file->is_database = true; /* TODO add an explanation */
}
else if (sscanf_result == 1)
{
elog(VERBOSE, "filename %s, filepath %s", filename, relative);
}
}
else if (path_is_prefix_of_path("base", relative))
{
file->tblspcOid = DEFAULTTABLESPACE_OID;
sscanf_result = sscanf(relative, "base/%u/%s", &(file->dbOid), filename);
elog(VERBOSE, "base sscanf result: %i", sscanf_result);
if (strcmp(relative, "base") == 0)
{
Assert(S_ISDIR(file->mode));
elog(VERBOSE, "the base itself, filepath %s", relative);
}
else if (sscanf_result == 1)
{
Assert(S_ISDIR(file->mode));
elog(VERBOSE, "dboid %u, filepath %s", file->dbOid, relative);
file->is_database = true;
}
else
{
elog(VERBOSE, "dboid %u, filename %s, filepath %s", file->dbOid, filename, relative);
}
}
else if (path_is_prefix_of_path(PG_TBLSPC_DIR, relative))
{
char temp_relative_path[MAXPGPATH];
sscanf_result = sscanf(relative, "pg_tblspc/%u/%s", &(file->tblspcOid), temp_relative_path);
elog(VERBOSE, "pg_tblspc sscanf result: %i", sscanf_result);
if (strcmp(relative, "pg_tblspc") == 0)
{
Assert(S_ISDIR(file->mode));
elog(VERBOSE, "the pg_tblspc itself, filepath %s", relative);
}
else if (sscanf_result == 1)
{
Assert(S_ISDIR(file->mode));
elog(VERBOSE, "tblspcOid %u, filepath %s", file->tblspcOid, relative);
}
else
{
/*continue parsing */
sscanf_result = sscanf(temp_relative_path+strlen(TABLESPACE_VERSION_DIRECTORY)+1, "%u/%s",
&(file->dbOid), filename);
elog(VERBOSE, "TABLESPACE_VERSION_DIRECTORY sscanf result: %i", sscanf_result);
if (sscanf_result == -1)
{
elog(VERBOSE, "The TABLESPACE_VERSION_DIRECTORY itself, filepath %s", relative);
}
else if (sscanf_result == 0)
{
/* Found file in pg_tblspc/tblsOid/TABLESPACE_VERSION_DIRECTORY
Legal only in case of 'pg_compression'
*/
if (strcmp(file->name, "pg_compression") == 0)
{
elog(VERBOSE, "Found pg_compression file in TABLESPACE_VERSION_DIRECTORY, filepath %s", relative);
/*Set every datafile in tablespace as is_cfs */
set_cfs_datafiles(files, root, relative, i);
}
else
{
elog(VERBOSE, "Found illegal file in TABLESPACE_VERSION_DIRECTORY, filepath %s", relative);
}
}
else if (sscanf_result == 1)
{
Assert(S_ISDIR(file->mode));
elog(VERBOSE, "dboid %u, filepath %s", file->dbOid, relative);
file->is_database = true;
}
else if (sscanf_result == 2)
{
elog(VERBOSE, "dboid %u, filename %s, filepath %s", file->dbOid, filename, relative);
}
else
{
elog(VERBOSE, "Illegal file filepath %s", relative);
}
}
}
else
{
elog(VERBOSE,"other dir or file, filepath %s", relative);
}
if (strcmp(filename, "ptrack_init") == 0)
{
/* Do not backup ptrack_init files */
pgFileFree(file);
parray_remove(files, i);
i--;
continue;
}
/* Check files located inside database directories */
if (filename[0] != '\0' && file->dbOid != 0)
{
if (strcmp(filename, "pg_internal.init") == 0)
{
/* Do not pg_internal.init files
* (they contain some cache entries, so it's fine) */
pgFileFree(file);
parray_remove(files, i);
i--;
continue;
}
else if (filename[0] == 't' && isdigit(filename[1]))
{
elog(VERBOSE, "temp file, filepath %s", relative);
/* Do not backup temp files */
pgFileFree(file);
parray_remove(files, i);
i--;
continue;
}
else if (isdigit(filename[0]))
{
/*
* TODO TODO TODO Files of this type can be compressed by cfs.
* Check that and do not mark them with 'is_datafile' flag.
*/
char *forkNameptr;
char suffix[MAXPGPATH];
forkNameptr = strstr(filename, "_");
if (forkNameptr != NULL)
{
/* auxiliary fork of the relfile */
sscanf(filename, "%u_%s", &(file->relOid), file->forkName);
elog(VERBOSE, "relOid %u, forkName %s, filepath %s", file->relOid, file->forkName, relative);
/* handle unlogged relations */
if (strcmp(file->forkName, "init") == 0)
{
/*
* Do not backup files of unlogged relations.
* scan filelist backward and exclude these files.
*/
int unlogged_file_num = i-1;
pgFile *unlogged_file = (pgFile *) parray_get(files, unlogged_file_num);
unlogged_file_reloid = file->relOid;
while (unlogged_file_num >= 0 &&
(unlogged_file_reloid != 0) &&
(unlogged_file->relOid == unlogged_file_reloid))
{
unlogged_file->size = 0;
pgFileFree(unlogged_file);
parray_remove(files, unlogged_file_num);
unlogged_file_num--;
i--;
unlogged_file = (pgFile *) parray_get(files, unlogged_file_num);
}
}
else if (strcmp(file->forkName, "ptrack") == 0)
{
/* Do not backup ptrack files */
pgFileFree(file);
parray_remove(files, i);
i--;
}
else if ((unlogged_file_reloid != 0) &&
(file->relOid == unlogged_file_reloid))
{
/* Do not backup forks of unlogged relations */
pgFileFree(file);
parray_remove(files, i);
i--;
}
continue;
}
sscanf_result = sscanf(filename, "%u.%d.%s", &(file->relOid), &(file->segno), suffix);
if (sscanf_result == 0)
{
elog(ERROR, "cannot parse filepath %s", relative);
}
else if (sscanf_result == 1)
{
/* first segment of the relfile */
elog(VERBOSE, "relOid %u, segno %d, filepath %s", file->relOid, 0, relative);
if (strcmp(relative + strlen(relative) - strlen("cfm"), "cfm") == 0)
{
/* reloid.cfm */
elog(VERBOSE, "Found cfm file %s", relative);
}
else
{
elog(VERBOSE, "Found first segment of the relfile %s", relative);
file->is_datafile = true;
}
}
else if (sscanf_result == 2)
{
/* not first segment of the relfile */
elog(VERBOSE, "relOid %u, segno %d, filepath %s", file->relOid, file->segno, relative);
file->is_datafile = true;
}
else
{
/*
* some cfs specific file.
* It is not datafile, because we cannot read it block by block
*/
elog(VERBOSE, "relOid %u, segno %d, suffix %s, filepath %s", file->relOid, file->segno, suffix, relative);
}
if ((unlogged_file_reloid != 0) &&
(file->relOid == unlogged_file_reloid))
{
/* Do not backup segments of unlogged files */
pgFileFree(file);
parray_remove(files, i);
i--;
}
}
}
}
}
/* If file is equal to pg_compression, then we consider this tablespace as
* cfs-compressed and should mark every file in this tablespace as cfs-file
* Setting is_cfs is done via going back through 'files' set every file
* that contain cfs_tablespace in his path as 'is_cfs'
* Goings back through array 'files' is valid option possible because of current
* sort rules:
* tblspcOid/TABLESPACE_VERSION_DIRECTORY
* tblspcOid/TABLESPACE_VERSION_DIRECTORY/dboid
* tblspcOid/TABLESPACE_VERSION_DIRECTORY/dboid/1
* tblspcOid/TABLESPACE_VERSION_DIRECTORY/dboid/1.cfm
* tblspcOid/TABLESPACE_VERSION_DIRECTORY/pg_compression
*/
static void
set_cfs_datafiles(parray *files, const char *root, char *relative, size_t i)
{
int len;
int p;
pgFile *prev_file;
char *cfs_tblspc_path;
char *relative_prev_file;
cfs_tblspc_path = strdup(relative);
len = strlen("/pg_compression");
cfs_tblspc_path[strlen(cfs_tblspc_path) - len] = 0;
elog(VERBOSE, "CFS DIRECTORY %s, pg_compression path: %s", cfs_tblspc_path, relative);
for (p = (int) i; p >= 0; p--)
{
prev_file = (pgFile *) parray_get(files, (size_t) p);
relative_prev_file = GetRelativePath(prev_file->path, root);
elog(VERBOSE, "Checking file in cfs tablespace %s", relative_prev_file);
if (strstr(relative_prev_file, cfs_tblspc_path) != NULL)
{
if (S_ISREG(prev_file->mode) && prev_file->is_datafile)
{
elog(VERBOSE, "Setting 'is_cfs' on file %s, name %s",
relative_prev_file, prev_file->name);
prev_file->is_cfs = true;
}
}
else
{
elog(VERBOSE, "Breaking on %s", relative_prev_file);
break;
}
}
free(cfs_tblspc_path);
}
/*
* Output the list of files to backup catalog DATABASE_FILE_LIST
*/
static void
write_backup_file_list(parray *files, const char *root)
{
FILE *fp;
char path[MAXPGPATH];
pgBackupGetPath(&current, path, lengthof(path), DATABASE_FILE_LIST);
fp = fopen(path, "wt");
if (fp == NULL)
elog(ERROR, "cannot open file list \"%s\": %s", path,
strerror(errno));
print_file_list(fp, files, root);
if (fflush(fp) != 0 ||
fsync(fileno(fp)) != 0 ||
fclose(fp))
elog(ERROR, "cannot write file list \"%s\": %s", path, strerror(errno));
}
/*
* A helper function to create the path of a relation file and segment.
* The returned path is palloc'd
*/
static char *
datasegpath(RelFileNode rnode, ForkNumber forknum, BlockNumber segno)
{
char *path;
char *segpath;
path = relpathperm(rnode, forknum);
if (segno > 0)
{
segpath = psprintf("%s.%u", path, segno);
pfree(path);
return segpath;
}
else
return path;
}
/*
* Find pgfile by given rnode in the backup_files_list
* and add given blkno to its pagemap.
*/
void
process_block_change(ForkNumber forknum, RelFileNode rnode, BlockNumber blkno)
{
char *path;
char *rel_path;
BlockNumber blkno_inseg;
int segno;
pgFile *file_item = NULL;
int j;
segno = blkno / RELSEG_SIZE;
blkno_inseg = blkno % RELSEG_SIZE;
rel_path = datasegpath(rnode, forknum, segno);
path = pg_malloc(strlen(rel_path) + strlen(pgdata) + 2);
sprintf(path, "%s/%s", pgdata, rel_path);
for (j = 0; j < parray_num(backup_files_list); j++)
{
pgFile *p = (pgFile *) parray_get(backup_files_list, j);
if (strcmp(p->path, path) == 0)
{
file_item = p;
break;
}
}
/*
* If we don't have any record of this file in the file map, it means
* that it's a relation that did not have much activity since the last
* backup. We can safely ignore it. If it is a new relation file, the
* backup would simply copy it as-is.
*/
if (file_item)
datapagemap_add(&file_item->pagemap, blkno_inseg);
pg_free(path);
pg_free(rel_path);
}
/*
* Given a list of files in the instance to backup, build a pagemap for each
* data file that has ptrack. Result is saved in the pagemap field of pgFile.
* NOTE we rely on the fact that provided parray is sorted by file->path.
*/
static void
make_pagemap_from_ptrack(parray *files)
{
size_t i;
Oid dbOid_with_ptrack_init = 0;
Oid tblspcOid_with_ptrack_init = 0;
char *ptrack_nonparsed = NULL;
size_t ptrack_nonparsed_size = 0;
for (i = 0; i < parray_num(files); i++)
{
pgFile *file = (pgFile *) parray_get(files, i);
size_t start_addr;
/*
* If there is a ptrack_init file in the database,
* we must backup all its files, ignoring ptrack files for relations.
*/
if (file->is_database)
{
char *filename = strrchr(file->path, '/');
Assert(filename != NULL);
filename++;
/*
* The function pg_ptrack_get_and_clear_db returns true
* if there was a ptrack_init file.
* Also ignore ptrack files for global tablespace,
* to avoid any possible specific errors.
*/
if ((file->tblspcOid == GLOBALTABLESPACE_OID) ||
pg_ptrack_get_and_clear_db(file->dbOid, file->tblspcOid))
{
dbOid_with_ptrack_init = file->dbOid;
tblspcOid_with_ptrack_init = file->tblspcOid;
}
}
if (file->is_datafile)
{
if (file->tblspcOid == tblspcOid_with_ptrack_init
&& file->dbOid == dbOid_with_ptrack_init)
{
/* ignore ptrack if ptrack_init exists */
elog(VERBOSE, "Ignoring ptrack because of ptrack_init for file: %s", file->path);
file->pagemap.bitmapsize = PageBitmapIsAbsent;
continue;
}
/* get ptrack bitmap once for all segments of the file */
if (file->segno == 0)
{
/* release previous value */
pg_free(ptrack_nonparsed);
ptrack_nonparsed_size = 0;
ptrack_nonparsed = pg_ptrack_get_and_clear(file->tblspcOid, file->dbOid,
file->relOid, &ptrack_nonparsed_size);
}
if (ptrack_nonparsed != NULL)
{
/*
* pg_ptrack_get_and_clear() returns ptrack with VARHDR cutted out.
* Compute the beginning of the ptrack map related to this segment
*
* HEAPBLOCKS_PER_BYTE. Number of heap pages one ptrack byte can track: 8
* RELSEG_SIZE. Number of Pages per segment: 131072
* RELSEG_SIZE/HEAPBLOCKS_PER_BYTE. number of bytes in ptrack file needed
* to keep track on one relsegment: 16384
*/
start_addr = (RELSEG_SIZE/HEAPBLOCKS_PER_BYTE)*file->segno;
if (start_addr + RELSEG_SIZE/HEAPBLOCKS_PER_BYTE > ptrack_nonparsed_size)
{
file->pagemap.bitmapsize = ptrack_nonparsed_size - start_addr;
elog(VERBOSE, "pagemap size: %i", file->pagemap.bitmapsize);
}
else
{
file->pagemap.bitmapsize = RELSEG_SIZE/HEAPBLOCKS_PER_BYTE;
elog(VERBOSE, "pagemap size: %i", file->pagemap.bitmapsize);
}
file->pagemap.bitmap = pg_malloc(file->pagemap.bitmapsize);
memcpy(file->pagemap.bitmap, ptrack_nonparsed+start_addr, file->pagemap.bitmapsize);
}
else
{
/*
* If ptrack file is missing, try to copy the entire file.
* It can happen in two cases:
* - files were created by commands that bypass buffer manager
* and, correspondingly, ptrack mechanism.
* i.e. CREATE DATABASE
* - target relation was deleted.
*/
elog(VERBOSE, "Ptrack is missing for file: %s", file->path);
file->pagemap.bitmapsize = PageBitmapIsAbsent;
}
}
}
}
/*
* Stop WAL streaming if current 'xlogpos' exceeds 'stop_backup_lsn', which is
* set by pg_stop_backup().
*/
static bool
stop_streaming(XLogRecPtr xlogpos, uint32 timeline, bool segment_finished)
{
static uint32 prevtimeline = 0;
static XLogRecPtr prevpos = InvalidXLogRecPtr;
/* we assume that we get called once at the end of each segment */
if (segment_finished)
elog(LOG, _("finished segment at %X/%X (timeline %u)\n"),
(uint32) (xlogpos >> 32), (uint32) xlogpos, timeline);
/*
* Note that we report the previous, not current, position here. After a
* timeline switch, xlogpos points to the beginning of the segment because
* that's where we always begin streaming. Reporting the end of previous
* timeline isn't totally accurate, because the next timeline can begin
* slightly before the end of the WAL that we received on the previous
* timeline, but it's close enough for reporting purposes.
*/
if (prevtimeline != 0 && prevtimeline != timeline)
elog(LOG, _("switched to timeline %u at %X/%X\n"),
timeline, (uint32) (prevpos >> 32), (uint32) prevpos);
if (!XLogRecPtrIsInvalid(stop_backup_lsn))
{
if (xlogpos > stop_backup_lsn)
return true;
/* pg_stop_backup() was executed, wait for the completion of stream */
if (stream_stop_timeout == 0)
{
elog(INFO, "Wait for LSN %X/%X to be streamed",
(uint32) (stop_backup_lsn >> 32), (uint32) stop_backup_lsn);
stream_stop_timeout = checkpoint_timeout();
stream_stop_timeout = stream_stop_timeout + stream_stop_timeout * 0.1;
stream_stop_begin = time(NULL);
}
if (time(NULL) - stream_stop_begin > stream_stop_timeout)
elog(ERROR, "Target LSN %X/%X could not be streamed in %d seconds",
(uint32) (stop_backup_lsn >> 32), (uint32) stop_backup_lsn,
stream_stop_timeout);
}
prevtimeline = timeline;
prevpos = xlogpos;
return false;
}
/*
* Start the log streaming
*/
static void
StreamLog(void *arg)
{
XLogRecPtr startpos;
TimeLineID starttli;
char *basedir = (char *)arg;
/*
* Connect in replication mode to the server
*/
if (conn == NULL)
conn = pgut_connect_replication(pgut_dbname);
if (!conn)
{
pthread_mutex_unlock(&start_stream_mut);
/* Error message already written in GetConnection() */
return;
}
if (!CheckServerVersionForStreaming(conn))
{
/*
* Error message already written in CheckServerVersionForStreaming().
* There's no hope of recovering from a version mismatch, so don't
* retry.
*/
disconnect_and_exit(1);
}
/*
* Identify server, obtaining start LSN position and current timeline ID
* at the same time, necessary if not valid data can be found in the
* existing output directory.
*/
if (!RunIdentifySystem(conn, NULL, &starttli, &startpos, NULL))
disconnect_and_exit(1);
/* Ok we have normal stream connect and main process can work again */
pthread_mutex_unlock(&start_stream_mut);
/*
* We must use startpos as start_lsn from start_backup
*/
startpos = current.start_lsn;
/*
* Always start streaming at the beginning of a segment
*/
startpos -= startpos % XLOG_SEG_SIZE;
/* Initialize timeout */
stream_stop_timeout = 0;
stream_stop_begin = 0;
/*
* Start the replication
*/
elog(LOG, _("starting log streaming at %X/%X (timeline %u)\n"),
(uint32) (startpos >> 32), (uint32) startpos, starttli);
#if PG_VERSION_NUM >= 90600
{
StreamCtl ctl;
MemSet(&ctl, 0, sizeof(ctl));
ctl.startpos = startpos;
ctl.timeline = starttli;
ctl.sysidentifier = NULL;
#if PG_VERSION_NUM >= 100000
ctl.walmethod = CreateWalDirectoryMethod(basedir, 0, true);
ctl.replication_slot = replication_slot;
ctl.stop_socket = PGINVALID_SOCKET;
#else
ctl.basedir = basedir;
#endif
ctl.stream_stop = stop_streaming;
ctl.standby_message_timeout = standby_message_timeout;
ctl.partial_suffix = NULL;
ctl.synchronous = false;
ctl.mark_done = false;
if(ReceiveXlogStream(conn, &ctl) == false)
elog(ERROR, "Problem in receivexlog");
#if PG_VERSION_NUM >= 100000
if (!ctl.walmethod->finish())
elog(ERROR, "Could not finish writing WAL files: %s",
strerror(errno));
#endif
}
#else
if(ReceiveXlogStream(conn, startpos, starttli, NULL, basedir,
stop_streaming, standby_message_timeout, NULL,
false, false) == false)
elog(ERROR, "Problem in receivexlog");
#endif
PQfinish(conn);
conn = NULL;
}
/*
* Get lsn of the moment when ptrack was enabled the last time.
*/
static XLogRecPtr
get_last_ptrack_lsn(void)
{
PGresult *res;
uint32 xlogid;
uint32 xrecoff;
XLogRecPtr lsn;
res = pgut_execute(backup_conn, "select pg_ptrack_control_lsn()", 0, NULL);
/* Extract timeline and LSN from results of pg_start_backup() */
XLogDataFromLSN(PQgetvalue(res, 0, 0), &xlogid, &xrecoff);
/* Calculate LSN */
lsn = (XLogRecPtr) ((uint64) xlogid << 32) | xrecoff;
PQclear(res);
return lsn;
}
Reference in New Issue View Git Blame Copy Permalink