postgresql/contrib/pg_upgrade/pg_upgrade.c

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/*
* pg_upgrade.c
*
* main source file
*
* Copyright (c) 2010-2013, PostgreSQL Global Development Group
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* contrib/pg_upgrade/pg_upgrade.c
*/
/*
* To simplify the upgrade process, we force certain system values to be
* identical between old and new clusters:
*
* We control all assignments of pg_class.oid (and relfilenode) so toast
* oids are the same between old and new clusters. This is important
* because toast oids are stored as toast pointers in user tables.
*
* FYI, while pg_class.oid and pg_class.relfilenode are initially the same
* in a cluster, but they can diverge due to CLUSTER, REINDEX, or VACUUM
* FULL. The new cluster will have matching pg_class.oid and
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* pg_class.relfilenode values and be based on the old oid value. This can
* cause the old and new pg_class.relfilenode values to differ. In summary,
* old and new pg_class.oid and new pg_class.relfilenode will have the
* same value, and old pg_class.relfilenode might differ.
*
* We control all assignments of pg_type.oid because these oids are stored
* in user composite type values.
*
* We control all assignments of pg_enum.oid because these oids are stored
* in user tables as enum values.
*
* We control all assignments of pg_authid.oid because these oids are stored
* in pg_largeobject_metadata.
*/
#include "postgres_fe.h"
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#include "pg_upgrade.h"
#ifdef HAVE_LANGINFO_H
#include <langinfo.h>
#endif
static void prepare_new_cluster(void);
static void prepare_new_databases(void);
static void create_new_objects(void);
static void copy_clog_xlog_xid(void);
static void set_frozenxids(void);
static void setup(char *argv0, bool *live_check);
static void cleanup(void);
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ClusterInfo old_cluster,
new_cluster;
OSInfo os_info;
char *output_files[] = {
SERVER_LOG_FILE,
#ifdef WIN32
/* unique file for pg_ctl start */
SERVER_START_LOG_FILE,
#endif
UTILITY_LOG_FILE,
INTERNAL_LOG_FILE,
NULL
};
int
main(int argc, char **argv)
{
char *sequence_script_file_name = NULL;
char *analyze_script_file_name = NULL;
char *deletion_script_file_name = NULL;
bool live_check = false;
parseCommandLine(argc, argv);
adjust_data_dir(&old_cluster);
adjust_data_dir(&new_cluster);
setup(argv[0], &live_check);
output_check_banner(live_check);
check_cluster_versions();
get_sock_dir(&old_cluster, live_check);
get_sock_dir(&new_cluster, false);
check_cluster_compatibility(live_check);
check_and_dump_old_cluster(live_check, &sequence_script_file_name);
/* -- NEW -- */
start_postmaster(&new_cluster, true);
check_new_cluster();
report_clusters_compatible();
pg_log(PG_REPORT, "\nPerforming Upgrade\n");
pg_log(PG_REPORT, "------------------\n");
prepare_new_cluster();
stop_postmaster(false);
/*
* Destructive Changes to New Cluster
*/
copy_clog_xlog_xid();
/* New now using xids of the old system */
/* -- NEW -- */
start_postmaster(&new_cluster, true);
prepare_new_databases();
create_new_objects();
stop_postmaster(false);
/*
* Most failures happen in create_new_objects(), which has completed at
* this point. We do this here because it is just before linking, which
* will link the old and new cluster data files, preventing the old
* cluster from being safely started once the new cluster is started.
*/
if (user_opts.transfer_mode == TRANSFER_MODE_LINK)
disable_old_cluster();
transfer_all_new_tablespaces(&old_cluster.dbarr, &new_cluster.dbarr,
old_cluster.pgdata, new_cluster.pgdata);
/*
* Assuming OIDs are only used in system tables, there is no need to
* restore the OID counter because we have not transferred any OIDs from
* the old system, but we do it anyway just in case. We do it late here
* because there is no need to have the schema load use new oids.
*/
prep_status("Setting next OID for new cluster");
exec_prog(UTILITY_LOG_FILE, NULL, true,
"\"%s/pg_resetxlog\" -o %u \"%s\"",
new_cluster.bindir, old_cluster.controldata.chkpnt_nxtoid,
new_cluster.pgdata);
check_ok();
prep_status("Sync data directory to disk");
exec_prog(UTILITY_LOG_FILE, NULL, true,
"\"%s/initdb\" --sync-only \"%s\"", new_cluster.bindir,
new_cluster.pgdata);
check_ok();
create_script_for_cluster_analyze(&analyze_script_file_name);
create_script_for_old_cluster_deletion(&deletion_script_file_name);
issue_warnings(sequence_script_file_name);
pg_log(PG_REPORT, "\nUpgrade Complete\n");
pg_log(PG_REPORT, "----------------\n");
output_completion_banner(analyze_script_file_name,
deletion_script_file_name);
pg_free(analyze_script_file_name);
pg_free(deletion_script_file_name);
pg_free(sequence_script_file_name);
cleanup();
return 0;
}
static void
setup(char *argv0, bool *live_check)
{
char exec_path[MAXPGPATH]; /* full path to my executable */
/*
* make sure the user has a clean environment, otherwise, we may confuse
* libpq when we connect to one (or both) of the servers.
*/
check_pghost_envvar();
verify_directories();
/* no postmasters should be running, except for a live check */
if (pid_lock_file_exists(old_cluster.pgdata))
{
/*
* If we have a postmaster.pid file, try to start the server. If it
* starts, the pid file was stale, so stop the server. If it doesn't
* start, assume the server is running. If the pid file is left over
* from a server crash, this also allows any committed transactions
* stored in the WAL to be replayed so they are not lost, because WAL
* files are not transfered from old to new servers.
*/
if (start_postmaster(&old_cluster, false))
stop_postmaster(false);
else
{
if (!user_opts.check)
pg_fatal("There seems to be a postmaster servicing the old cluster.\n"
"Please shutdown that postmaster and try again.\n");
else
*live_check = true;
}
}
/* same goes for the new postmaster */
if (pid_lock_file_exists(new_cluster.pgdata))
{
if (start_postmaster(&new_cluster, false))
stop_postmaster(false);
else
pg_fatal("There seems to be a postmaster servicing the new cluster.\n"
"Please shutdown that postmaster and try again.\n");
}
/* get path to pg_upgrade executable */
if (find_my_exec(argv0, exec_path) < 0)
pg_fatal("Could not get path name to pg_upgrade: %s\n", getErrorText(errno));
/* Trim off program name and keep just path */
*last_dir_separator(exec_path) = '\0';
canonicalize_path(exec_path);
os_info.exec_path = pg_strdup(exec_path);
}
static void
prepare_new_cluster(void)
{
/*
* It would make more sense to freeze after loading the schema, but that
* would cause us to lose the frozenids restored by the load. We use
* --analyze so autovacuum doesn't update statistics later
*/
prep_status("Analyzing all rows in the new cluster");
exec_prog(UTILITY_LOG_FILE, NULL, true,
"\"%s/vacuumdb\" %s --all --analyze %s",
new_cluster.bindir, cluster_conn_opts(&new_cluster),
log_opts.verbose ? "--verbose" : "");
check_ok();
/*
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* We do freeze after analyze so pg_statistic is also frozen. template0 is
* not frozen here, but data rows were frozen by initdb, and we set its
* datfrozenxid and relfrozenxids later to match the new xid counter
* later.
*/
prep_status("Freezing all rows on the new cluster");
exec_prog(UTILITY_LOG_FILE, NULL, true,
"\"%s/vacuumdb\" %s --all --freeze %s",
new_cluster.bindir, cluster_conn_opts(&new_cluster),
log_opts.verbose ? "--verbose" : "");
check_ok();
get_pg_database_relfilenode(&new_cluster);
}
static void
prepare_new_databases(void)
{
/*
* We set autovacuum_freeze_max_age to its maximum value so autovacuum
* does not launch here and delete clog files, before the frozen xids are
* set.
*/
set_frozenxids();
prep_status("Restoring global objects in the new cluster");
/*
* Install support functions in the global-object restore database to
* preserve pg_authid.oid. pg_dumpall uses 'template0' as its template
* database so objects we add into 'template1' are not propogated. They
* are removed on pg_upgrade exit.
*/
install_support_functions_in_new_db("template1");
/*
* We have to create the databases first so we can install support
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* functions in all the other databases. Ideally we could create the
* support functions in template1 but pg_dumpall creates database using
* the template0 template.
*/
exec_prog(UTILITY_LOG_FILE, NULL, true,
"\"%s/psql\" " EXEC_PSQL_ARGS " %s -f \"%s\"",
new_cluster.bindir, cluster_conn_opts(&new_cluster),
GLOBALS_DUMP_FILE);
check_ok();
/* we load this to get a current list of databases */
get_db_and_rel_infos(&new_cluster);
}
static void
create_new_objects(void)
{
int dbnum;
prep_status("Adding support functions to new cluster");
/*
* Technically, we only need to install these support functions in new
* databases that also exist in the old cluster, but for completeness we
* process all new databases.
*/
for (dbnum = 0; dbnum < new_cluster.dbarr.ndbs; dbnum++)
{
DbInfo *new_db = &new_cluster.dbarr.dbs[dbnum];
/* skip db we already installed */
if (strcmp(new_db->db_name, "template1") != 0)
install_support_functions_in_new_db(new_db->db_name);
}
check_ok();
prep_status("Restoring database schemas in the new cluster\n");
for (dbnum = 0; dbnum < old_cluster.dbarr.ndbs; dbnum++)
{
char sql_file_name[MAXPGPATH],
log_file_name[MAXPGPATH];
DbInfo *old_db = &old_cluster.dbarr.dbs[dbnum];
pg_log(PG_STATUS, "%s", old_db->db_name);
snprintf(sql_file_name, sizeof(sql_file_name), DB_DUMP_FILE_MASK, old_db->db_oid);
snprintf(log_file_name, sizeof(log_file_name), DB_DUMP_LOG_FILE_MASK, old_db->db_oid);
/*
* pg_dump only produces its output at the end, so there is little
* parallelism if using the pipe.
*/
parallel_exec_prog(log_file_name,
NULL,
"\"%s/pg_restore\" %s --exit-on-error --verbose --dbname \"%s\" \"%s\"",
new_cluster.bindir,
cluster_conn_opts(&new_cluster),
old_db->db_name,
sql_file_name);
}
/* reap all children */
while (reap_child(true) == true)
;
end_progress_output();
check_ok();
/* regenerate now that we have objects in the databases */
get_db_and_rel_infos(&new_cluster);
uninstall_support_functions_from_new_cluster();
}
/*
* Delete the given subdirectory contents from the new cluster, and copy the
* files from the old cluster into it.
*/
static void
copy_subdir_files(char *subdir)
{
char old_path[MAXPGPATH];
char new_path[MAXPGPATH];
prep_status("Deleting files from new %s", subdir);
snprintf(old_path, sizeof(old_path), "%s/%s", old_cluster.pgdata, subdir);
snprintf(new_path, sizeof(new_path), "%s/%s", new_cluster.pgdata, subdir);
if (!rmtree(new_path, true))
pg_fatal("could not delete directory \"%s\"\n", new_path);
check_ok();
prep_status("Copying old %s to new server", subdir);
exec_prog(UTILITY_LOG_FILE, NULL, true,
#ifndef WIN32
"cp -Rf \"%s\" \"%s\"",
#else
/* flags: everything, no confirm, quiet, overwrite read-only */
"xcopy /e /y /q /r \"%s\" \"%s\\\"",
#endif
old_path, new_path);
check_ok();
}
static void
copy_clog_xlog_xid(void)
{
/* copy old commit logs to new data dir */
copy_subdir_files("pg_clog");
/* set the next transaction id of the new cluster */
prep_status("Setting next transaction ID for new cluster");
exec_prog(UTILITY_LOG_FILE, NULL, true,
"\"%s/pg_resetxlog\" -f -x %u \"%s\"",
new_cluster.bindir, old_cluster.controldata.chkpnt_nxtxid,
new_cluster.pgdata);
check_ok();
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
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/*
* If the old server is before the MULTIXACT_FORMATCHANGE_CAT_VER change
* (see pg_upgrade.h) and the new server is after, then we don't copy
* pg_multixact files, but we need to reset pg_control so that the new
* server doesn't attempt to read multis older than the cutoff value.
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
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*/
if (old_cluster.controldata.cat_ver >= MULTIXACT_FORMATCHANGE_CAT_VER &&
new_cluster.controldata.cat_ver >= MULTIXACT_FORMATCHANGE_CAT_VER)
{
copy_subdir_files("pg_multixact/offsets");
copy_subdir_files("pg_multixact/members");
prep_status("Setting next multixact ID and offset for new cluster");
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
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/*
* we preserve all files and contents, so we must preserve both "next"
* counters here and the oldest multi present on system.
*/
exec_prog(UTILITY_LOG_FILE, NULL, true,
"\"%s/pg_resetxlog\" -O %u -m %u,%u \"%s\"",
new_cluster.bindir,
old_cluster.controldata.chkpnt_nxtmxoff,
old_cluster.controldata.chkpnt_nxtmulti,
old_cluster.controldata.chkpnt_oldstMulti,
new_cluster.pgdata);
check_ok();
}
else if (new_cluster.controldata.cat_ver >= MULTIXACT_FORMATCHANGE_CAT_VER)
{
prep_status("Setting oldest multixact ID on new cluster");
Improve concurrency of foreign key locking This patch introduces two additional lock modes for tuples: "SELECT FOR KEY SHARE" and "SELECT FOR NO KEY UPDATE". These don't block each other, in contrast with already existing "SELECT FOR SHARE" and "SELECT FOR UPDATE". UPDATE commands that do not modify the values stored in the columns that are part of the key of the tuple now grab a SELECT FOR NO KEY UPDATE lock on the tuple, allowing them to proceed concurrently with tuple locks of the FOR KEY SHARE variety. Foreign key triggers now use FOR KEY SHARE instead of FOR SHARE; this means the concurrency improvement applies to them, which is the whole point of this patch. The added tuple lock semantics require some rejiggering of the multixact module, so that the locking level that each transaction is holding can be stored alongside its Xid. Also, multixacts now need to persist across server restarts and crashes, because they can now represent not only tuple locks, but also tuple updates. This means we need more careful tracking of lifetime of pg_multixact SLRU files; since they now persist longer, we require more infrastructure to figure out when they can be removed. pg_upgrade also needs to be careful to copy pg_multixact files over from the old server to the new, or at least part of multixact.c state, depending on the versions of the old and new servers. Tuple time qualification rules (HeapTupleSatisfies routines) need to be careful not to consider tuples with the "is multi" infomask bit set as being only locked; they might need to look up MultiXact values (i.e. possibly do pg_multixact I/O) to find out the Xid that updated a tuple, whereas they previously were assured to only use information readily available from the tuple header. This is considered acceptable, because the extra I/O would involve cases that would previously cause some commands to block waiting for concurrent transactions to finish. Another important change is the fact that locking tuples that have previously been updated causes the future versions to be marked as locked, too; this is essential for correctness of foreign key checks. This causes additional WAL-logging, also (there was previously a single WAL record for a locked tuple; now there are as many as updated copies of the tuple there exist.) With all this in place, contention related to tuples being checked by foreign key rules should be much reduced. As a bonus, the old behavior that a subtransaction grabbing a stronger tuple lock than the parent (sub)transaction held on a given tuple and later aborting caused the weaker lock to be lost, has been fixed. Many new spec files were added for isolation tester framework, to ensure overall behavior is sane. There's probably room for several more tests. There were several reviewers of this patch; in particular, Noah Misch and Andres Freund spent considerable time in it. Original idea for the patch came from Simon Riggs, after a problem report by Joel Jacobson. Most code is from me, with contributions from Marti Raudsepp, Alexander Shulgin, Noah Misch and Andres Freund. This patch was discussed in several pgsql-hackers threads; the most important start at the following message-ids: AANLkTimo9XVcEzfiBR-ut3KVNDkjm2Vxh+t8kAmWjPuv@mail.gmail.com 1290721684-sup-3951@alvh.no-ip.org 1294953201-sup-2099@alvh.no-ip.org 1320343602-sup-2290@alvh.no-ip.org 1339690386-sup-8927@alvh.no-ip.org 4FE5FF020200002500048A3D@gw.wicourts.gov 4FEAB90A0200002500048B7D@gw.wicourts.gov
2013-01-23 23:04:59 +08:00
/*
* We don't preserve files in this case, but it's important that the
* oldest multi is set to the latest value used by the old system, so
* that multixact.c returns the empty set for multis that might be
* present on disk. We set next multi to the value following that; it
* might end up wrapped around (i.e. 0) if the old cluster had
* next=MaxMultiXactId, but multixact.c can cope with that just fine.
*/
exec_prog(UTILITY_LOG_FILE, NULL, true,
"\"%s/pg_resetxlog\" -m %u,%u \"%s\"",
new_cluster.bindir,
old_cluster.controldata.chkpnt_nxtmulti + 1,
old_cluster.controldata.chkpnt_nxtmulti,
new_cluster.pgdata);
check_ok();
}
/* now reset the wal archives in the new cluster */
prep_status("Resetting WAL archives");
exec_prog(UTILITY_LOG_FILE, NULL, true,
"\"%s/pg_resetxlog\" -l %s \"%s\"", new_cluster.bindir,
old_cluster.controldata.nextxlogfile,
new_cluster.pgdata);
check_ok();
}
/*
* set_frozenxids()
*
* We have frozen all xids, so set relfrozenxid and datfrozenxid
* to be the old cluster's xid counter, which we just set in the new
* cluster. User-table frozenxid values will be set by pg_dumpall
* --binary-upgrade, but objects not set by the pg_dump must have
* proper frozen counters.
*/
static
void
set_frozenxids(void)
{
int dbnum;
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PGconn *conn,
*conn_template1;
PGresult *dbres;
int ntups;
int i_datname;
int i_datallowconn;
prep_status("Setting frozenxid counters in new cluster");
conn_template1 = connectToServer(&new_cluster, "template1");
/* set pg_database.datfrozenxid */
PQclear(executeQueryOrDie(conn_template1,
"UPDATE pg_catalog.pg_database "
"SET datfrozenxid = '%u'",
old_cluster.controldata.chkpnt_nxtxid));
/* get database names */
dbres = executeQueryOrDie(conn_template1,
"SELECT datname, datallowconn "
"FROM pg_catalog.pg_database");
i_datname = PQfnumber(dbres, "datname");
i_datallowconn = PQfnumber(dbres, "datallowconn");
ntups = PQntuples(dbres);
for (dbnum = 0; dbnum < ntups; dbnum++)
{
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char *datname = PQgetvalue(dbres, dbnum, i_datname);
char *datallowconn = PQgetvalue(dbres, dbnum, i_datallowconn);
/*
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* We must update databases where datallowconn = false, e.g.
* template0, because autovacuum increments their datfrozenxids and
* relfrozenxids even if autovacuum is turned off, and even though all
* the data rows are already frozen To enable this, we temporarily
* change datallowconn.
*/
if (strcmp(datallowconn, "f") == 0)
PQclear(executeQueryOrDie(conn_template1,
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"UPDATE pg_catalog.pg_database "
"SET datallowconn = true "
"WHERE datname = '%s'", datname));
conn = connectToServer(&new_cluster, datname);
/* set pg_class.relfrozenxid */
PQclear(executeQueryOrDie(conn,
"UPDATE pg_catalog.pg_class "
"SET relfrozenxid = '%u' "
/* only heap, materialized view, and TOAST are vacuumed */
"WHERE relkind IN ('r', 'm', 't')",
old_cluster.controldata.chkpnt_nxtxid));
PQfinish(conn);
/* Reset datallowconn flag */
if (strcmp(datallowconn, "f") == 0)
PQclear(executeQueryOrDie(conn_template1,
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"UPDATE pg_catalog.pg_database "
"SET datallowconn = false "
"WHERE datname = '%s'", datname));
}
PQclear(dbres);
PQfinish(conn_template1);
check_ok();
}
static void
cleanup(void)
{
fclose(log_opts.internal);
/* Remove dump and log files? */
if (!log_opts.retain)
{
int dbnum;
char **filename;
for (filename = output_files; *filename != NULL; filename++)
unlink(*filename);
/* remove dump files */
unlink(GLOBALS_DUMP_FILE);
if (old_cluster.dbarr.dbs)
for (dbnum = 0; dbnum < old_cluster.dbarr.ndbs; dbnum++)
{
char sql_file_name[MAXPGPATH],
log_file_name[MAXPGPATH];
DbInfo *old_db = &old_cluster.dbarr.dbs[dbnum];
snprintf(sql_file_name, sizeof(sql_file_name), DB_DUMP_FILE_MASK, old_db->db_oid);
unlink(sql_file_name);
snprintf(log_file_name, sizeof(log_file_name), DB_DUMP_LOG_FILE_MASK, old_db->db_oid);
unlink(log_file_name);
}
}
}