diff options
-rw-r--r-- | doc/src/sgml/config.sgml | 34 | ||||
-rw-r--r-- | doc/src/sgml/high-availability.sgml | 5 | ||||
-rw-r--r-- | doc/src/sgml/runtime.sgml | 10 | ||||
-rw-r--r-- | src/backend/access/rmgrdesc/xlogdesc.c | 7 | ||||
-rw-r--r-- | src/backend/access/transam/xlog.c | 10 | ||||
-rw-r--r-- | src/backend/postmaster/postmaster.c | 8 | ||||
-rw-r--r-- | src/backend/replication/walsender.c | 12 | ||||
-rw-r--r-- | src/backend/storage/lmgr/proc.c | 23 | ||||
-rw-r--r-- | src/backend/utils/init/postinit.c | 11 | ||||
-rw-r--r-- | src/backend/utils/misc/guc.c | 23 | ||||
-rw-r--r-- | src/bin/pg_controldata/pg_controldata.c | 2 | ||||
-rw-r--r-- | src/bin/pg_resetwal/pg_resetwal.c | 2 | ||||
-rw-r--r-- | src/include/access/xlog_internal.h | 3 | ||||
-rw-r--r-- | src/include/catalog/pg_control.h | 3 | ||||
-rw-r--r-- | src/include/storage/proc.h | 2 |
15 files changed, 100 insertions, 55 deletions
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 7e208a4b812..07b847a8e96 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -697,8 +697,7 @@ include_dir 'conf.d' <para> The default value is three connections. The value must be less - than <varname>max_connections</varname> minus - <xref linkend="guc-max-wal-senders"/>. + than <varname>max_connections</varname>. This parameter can only be set at server start. </para> </listitem> @@ -3495,24 +3494,25 @@ restore_command = 'copy "C:\\server\\archivedir\\%f" "%p"' # Windows </term> <listitem> <para> - Specifies the maximum number of concurrent connections from - standby servers or streaming base backup clients (i.e., the - maximum number of simultaneously running WAL sender - processes). The default is 10. The value 0 means replication is - disabled. WAL sender processes count towards the total number - of connections, so this parameter's value must be less than - <xref linkend="guc-max-connections"/> minus - <xref linkend="guc-superuser-reserved-connections"/>. - Abrupt streaming client disconnection might leave an orphaned - connection slot behind until - a timeout is reached, so this parameter should be set slightly - higher than the maximum number of expected clients so disconnected - clients can immediately reconnect. This parameter can only - be set at server start. - Also, <varname>wal_level</varname> must be set to + Specifies the maximum number of concurrent connections from standby + servers or streaming base backup clients (i.e., the maximum number of + simultaneously running WAL sender processes). The default is + <literal>10</literal>. The value <literal>0</literal> means + replication is disabled. Abrupt streaming client disconnection might + leave an orphaned connection slot behind until a timeout is reached, + so this parameter should be set slightly higher than the maximum + number of expected clients so disconnected clients can immediately + reconnect. This parameter can only be set at server start. Also, + <varname>wal_level</varname> must be set to <literal>replica</literal> or higher to allow connections from standby servers. </para> + + <para> + When running a standby server, you must set this parameter to the + same or higher value than on the master server. Otherwise, queries + will not be allowed in the standby server. + </para> </listitem> </varlistentry> diff --git a/doc/src/sgml/high-availability.sgml b/doc/src/sgml/high-availability.sgml index bbab7395a21..2b4dcd03c87 100644 --- a/doc/src/sgml/high-availability.sgml +++ b/doc/src/sgml/high-availability.sgml @@ -2179,6 +2179,11 @@ LOG: database system is ready to accept read only connections </listitem> <listitem> <para> + <varname>max_wal_senders</varname> + </para> + </listitem> + <listitem> + <para> <varname>max_worker_processes</varname> </para> </listitem> diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml index 1f78f6c9569..7de26e98ad8 100644 --- a/doc/src/sgml/runtime.sgml +++ b/doc/src/sgml/runtime.sgml @@ -720,13 +720,13 @@ psql: could not connect to server: No such file or directory <row> <entry><varname>SEMMNI</varname></entry> <entry>Maximum number of semaphore identifiers (i.e., sets)</entry> - <entry>at least <literal>ceil((max_connections + autovacuum_max_workers + max_worker_processes + 5) / 16)</literal> plus room for other applications</entry> + <entry>at least <literal>ceil((max_connections + autovacuum_max_workers + wax_wal_senders + max_worker_processes + 5) / 16)</literal> plus room for other applications</entry> </row> <row> <entry><varname>SEMMNS</varname></entry> <entry>Maximum number of semaphores system-wide</entry> - <entry><literal>ceil((max_connections + autovacuum_max_workers + max_worker_processes + 5) / 16) * 17</literal> plus room for other applications</entry> + <entry><literal>ceil((max_connections + autovacuum_max_workers + max_wal_senders + max_worker_processes + 5) / 16) * 17</literal> plus room for other applications</entry> </row> <row> @@ -785,13 +785,13 @@ psql: could not connect to server: No such file or directory other applications. The maximum number of semaphores in the system is set by <varname>SEMMNS</varname>, which consequently must be at least as high as <varname>max_connections</varname> plus - <varname>autovacuum_max_workers</varname> plus <varname>max_worker_processes</varname>, - plus one extra for each 16 + <varname>autovacuum_max_workers</varname> plus <varname>max_wal_senders</varname>, + plus <varname>max_worker_processes</varname>, plus one extra for each 16 allowed connections plus workers (see the formula in <xref linkend="sysvipc-parameters"/>). The parameter <varname>SEMMNI</varname> determines the limit on the number of semaphore sets that can exist on the system at one time. Hence this parameter must be at - least <literal>ceil((max_connections + autovacuum_max_workers + max_worker_processes + 5) / 16)</literal>. + least <literal>ceil((max_connections + autovacuum_max_workers + max_wal_senders + max_worker_processes + 5) / 16)</literal>. Lowering the number of allowed connections is a temporary workaround for failures, which are usually confusingly worded <quote>No space diff --git a/src/backend/access/rmgrdesc/xlogdesc.c b/src/backend/access/rmgrdesc/xlogdesc.c index 7f732516963..0ad4454a8c6 100644 --- a/src/backend/access/rmgrdesc/xlogdesc.c +++ b/src/backend/access/rmgrdesc/xlogdesc.c @@ -110,10 +110,11 @@ xlog_desc(StringInfo buf, XLogReaderState *record) } appendStringInfo(buf, "max_connections=%d max_worker_processes=%d " - "max_prepared_xacts=%d max_locks_per_xact=%d " - "wal_level=%s wal_log_hints=%s " - "track_commit_timestamp=%s", + "max_wal_senders=%d max_prepared_xacts=%d " + "max_locks_per_xact=%d wal_level=%s " + "wal_log_hints=%s track_commit_timestamp=%s", xlrec.MaxConnections, + xlrec.max_wal_senders, xlrec.max_worker_processes, xlrec.max_prepared_xacts, xlrec.max_locks_per_xact, diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c index a9f32728495..ecd12fc53ae 100644 --- a/src/backend/access/transam/xlog.c +++ b/src/backend/access/transam/xlog.c @@ -5257,6 +5257,7 @@ BootStrapXLOG(void) /* Set important parameter values for use when replaying WAL */ ControlFile->MaxConnections = MaxConnections; ControlFile->max_worker_processes = max_worker_processes; + ControlFile->max_wal_senders = max_wal_senders; ControlFile->max_prepared_xacts = max_prepared_xacts; ControlFile->max_locks_per_xact = max_locks_per_xact; ControlFile->wal_level = wal_level; @@ -6170,6 +6171,9 @@ CheckRequiredParameterValues(void) RecoveryRequiresIntParameter("max_worker_processes", max_worker_processes, ControlFile->max_worker_processes); + RecoveryRequiresIntParameter("max_wal_senders", + max_wal_senders, + ControlFile->max_wal_senders); RecoveryRequiresIntParameter("max_prepared_transactions", max_prepared_xacts, ControlFile->max_prepared_xacts); @@ -9460,6 +9464,7 @@ XLogReportParameters(void) wal_log_hints != ControlFile->wal_log_hints || MaxConnections != ControlFile->MaxConnections || max_worker_processes != ControlFile->max_worker_processes || + max_wal_senders != ControlFile->max_wal_senders || max_prepared_xacts != ControlFile->max_prepared_xacts || max_locks_per_xact != ControlFile->max_locks_per_xact || track_commit_timestamp != ControlFile->track_commit_timestamp) @@ -9478,6 +9483,7 @@ XLogReportParameters(void) xlrec.MaxConnections = MaxConnections; xlrec.max_worker_processes = max_worker_processes; + xlrec.max_wal_senders = max_wal_senders; xlrec.max_prepared_xacts = max_prepared_xacts; xlrec.max_locks_per_xact = max_locks_per_xact; xlrec.wal_level = wal_level; @@ -9493,6 +9499,7 @@ XLogReportParameters(void) ControlFile->MaxConnections = MaxConnections; ControlFile->max_worker_processes = max_worker_processes; + ControlFile->max_wal_senders = max_wal_senders; ControlFile->max_prepared_xacts = max_prepared_xacts; ControlFile->max_locks_per_xact = max_locks_per_xact; ControlFile->wal_level = wal_level; @@ -9896,6 +9903,7 @@ xlog_redo(XLogReaderState *record) LWLockAcquire(ControlFileLock, LW_EXCLUSIVE); ControlFile->MaxConnections = xlrec.MaxConnections; ControlFile->max_worker_processes = xlrec.max_worker_processes; + ControlFile->max_wal_senders = xlrec.max_wal_senders; ControlFile->max_prepared_xacts = xlrec.max_prepared_xacts; ControlFile->max_locks_per_xact = xlrec.max_locks_per_xact; ControlFile->wal_level = xlrec.wal_level; @@ -9927,7 +9935,7 @@ xlog_redo(XLogReaderState *record) UpdateControlFile(); LWLockRelease(ControlFileLock); - /* Check to see if any changes to max_connections give problems */ + /* Check to see if any parameter change gives a problem on recovery */ CheckRequiredParameterValues(); } else if (info == XLOG_FPW_CHANGE) diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c index 40a0222220d..ccea231e985 100644 --- a/src/backend/postmaster/postmaster.c +++ b/src/backend/postmaster/postmaster.c @@ -885,11 +885,11 @@ PostmasterMain(int argc, char *argv[]) /* * Check for invalid combinations of GUC settings. */ - if (ReservedBackends + max_wal_senders >= MaxConnections) + if (ReservedBackends >= MaxConnections) { - write_stderr("%s: superuser_reserved_connections (%d) plus max_wal_senders (%d) must be less than max_connections (%d)\n", + write_stderr("%s: superuser_reserved_connections (%d) must be less than max_connections (%d)\n", progname, - ReservedBackends, max_wal_senders, MaxConnections); + ReservedBackends, MaxConnections); ExitPostmaster(1); } if (XLogArchiveMode > ARCHIVE_MODE_OFF && wal_level == WAL_LEVEL_MINIMAL) @@ -5532,7 +5532,7 @@ int MaxLivePostmasterChildren(void) { return 2 * (MaxConnections + autovacuum_max_workers + 1 + - max_worker_processes); + max_wal_senders + max_worker_processes); } /* diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c index 2d2eb23eb73..9b143f361b8 100644 --- a/src/backend/replication/walsender.c +++ b/src/backend/replication/walsender.c @@ -2273,8 +2273,8 @@ InitWalSenderSlot(void) Assert(MyWalSnd == NULL); /* - * Find a free walsender slot and reserve it. If this fails, we must be - * out of WalSnd structures. + * Find a free walsender slot and reserve it. This must not fail due to + * the prior check for free WAL senders in InitProcess(). */ for (i = 0; i < max_wal_senders; i++) { @@ -2310,12 +2310,8 @@ InitWalSenderSlot(void) break; } } - if (MyWalSnd == NULL) - ereport(FATAL, - (errcode(ERRCODE_TOO_MANY_CONNECTIONS), - errmsg("number of requested standby connections " - "exceeds max_wal_senders (currently %d)", - max_wal_senders))); + + Assert(MyWalSnd != NULL); /* Arrange to clean up at walsender exit */ on_shmem_exit(WalSndKill, 0); diff --git a/src/backend/storage/lmgr/proc.c b/src/backend/storage/lmgr/proc.c index 89c80fb6874..0da5b19719f 100644 --- a/src/backend/storage/lmgr/proc.c +++ b/src/backend/storage/lmgr/proc.c @@ -43,6 +43,7 @@ #include "postmaster/autovacuum.h" #include "replication/slot.h" #include "replication/syncrep.h" +#include "replication/walsender.h" #include "storage/condition_variable.h" #include "storage/standby.h" #include "storage/ipc.h" @@ -147,8 +148,9 @@ ProcGlobalSemas(void) * running out when trying to start another backend is a common failure. * So, now we grab enough semaphores to support the desired max number * of backends immediately at initialization --- if the sysadmin has set - * MaxConnections, max_worker_processes, or autovacuum_max_workers higher - * than his kernel will support, he'll find out sooner rather than later. + * MaxConnections, max_worker_processes, max_wal_senders, or + * autovacuum_max_workers higher than his kernel will support, he'll + * find out sooner rather than later. * * Another reason for creating semaphores here is that the semaphore * implementation typically requires us to create semaphores in the @@ -180,6 +182,7 @@ InitProcGlobal(void) ProcGlobal->freeProcs = NULL; ProcGlobal->autovacFreeProcs = NULL; ProcGlobal->bgworkerFreeProcs = NULL; + ProcGlobal->walsenderFreeProcs = NULL; ProcGlobal->startupProc = NULL; ProcGlobal->startupProcPid = 0; ProcGlobal->startupBufferPinWaitBufId = -1; @@ -253,13 +256,20 @@ InitProcGlobal(void) ProcGlobal->autovacFreeProcs = &procs[i]; procs[i].procgloballist = &ProcGlobal->autovacFreeProcs; } - else if (i < MaxBackends) + else if (i < MaxConnections + autovacuum_max_workers + 1 + max_worker_processes) { /* PGPROC for bgworker, add to bgworkerFreeProcs list */ procs[i].links.next = (SHM_QUEUE *) ProcGlobal->bgworkerFreeProcs; ProcGlobal->bgworkerFreeProcs = &procs[i]; procs[i].procgloballist = &ProcGlobal->bgworkerFreeProcs; } + else if (i < MaxBackends) + { + /* PGPROC for walsender, add to walsenderFreeProcs list */ + procs[i].links.next = (SHM_QUEUE *) ProcGlobal->walsenderFreeProcs; + ProcGlobal->walsenderFreeProcs = &procs[i]; + procs[i].procgloballist = &ProcGlobal->walsenderFreeProcs; + } /* Initialize myProcLocks[] shared memory queues. */ for (j = 0; j < NUM_LOCK_PARTITIONS; j++) @@ -311,6 +321,8 @@ InitProcess(void) procgloballist = &ProcGlobal->autovacFreeProcs; else if (IsBackgroundWorker) procgloballist = &ProcGlobal->bgworkerFreeProcs; + else if (am_walsender) + procgloballist = &ProcGlobal->walsenderFreeProcs; else procgloballist = &ProcGlobal->freeProcs; @@ -341,6 +353,11 @@ InitProcess(void) * in the autovacuum case? */ SpinLockRelease(ProcStructLock); + if (am_walsender) + ereport(FATAL, + (errcode(ERRCODE_TOO_MANY_CONNECTIONS), + errmsg("number of requested standby connections exceeds max_wal_senders (currently %d)", + max_wal_senders))); ereport(FATAL, (errcode(ERRCODE_TOO_MANY_CONNECTIONS), errmsg("sorry, too many clients already"))); diff --git a/src/backend/utils/init/postinit.c b/src/backend/utils/init/postinit.c index c0b62314580..a5ee209f910 100644 --- a/src/backend/utils/init/postinit.c +++ b/src/backend/utils/init/postinit.c @@ -527,7 +527,7 @@ InitializeMaxBackends(void) /* the extra unit accounts for the autovacuum launcher */ MaxBackends = MaxConnections + autovacuum_max_workers + 1 + - max_worker_processes; + max_worker_processes + max_wal_senders; /* internal error because the values were all checked previously */ if (MaxBackends > MAX_BACKENDS) @@ -811,12 +811,11 @@ InitPostgres(const char *in_dbname, Oid dboid, const char *username, } /* - * The last few connection slots are reserved for superusers. Although - * replication connections currently require superuser privileges, we - * don't allow them to consume the reserved slots, which are intended for - * interactive use. + * The last few connection slots are reserved for superusers. Replication + * connections are drawn from slots reserved with max_wal_senders and not + * limited by max_connections or superuser_reserved_connections. */ - if ((!am_superuser || am_walsender) && + if (!am_superuser && !am_walsender && ReservedBackends > 0 && !HaveNFreeProcs(ReservedBackends)) ereport(FATAL, diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c index ea5444c6f15..41d477165cd 100644 --- a/src/backend/utils/misc/guc.c +++ b/src/backend/utils/misc/guc.c @@ -187,6 +187,7 @@ static const char *show_tcp_keepalives_count(void); static bool check_maxconnections(int *newval, void **extra, GucSource source); static bool check_max_worker_processes(int *newval, void **extra, GucSource source); static bool check_autovacuum_max_workers(int *newval, void **extra, GucSource source); +static bool check_max_wal_senders(int *newval, void **extra, GucSource source); static bool check_autovacuum_work_mem(int *newval, void **extra, GucSource source); static bool check_effective_io_concurrency(int *newval, void **extra, GucSource source); static void assign_effective_io_concurrency(int newval, void *extra); @@ -2090,7 +2091,7 @@ static struct config_int ConfigureNamesInt[] = }, { - /* see max_connections and max_wal_senders */ + /* see max_connections */ {"superuser_reserved_connections", PGC_POSTMASTER, CONN_AUTH_SETTINGS, gettext_noop("Sets the number of connection slots reserved for superusers."), NULL @@ -2608,14 +2609,13 @@ static struct config_int ConfigureNamesInt[] = }, { - /* see max_connections and superuser_reserved_connections */ {"max_wal_senders", PGC_POSTMASTER, REPLICATION_SENDING, gettext_noop("Sets the maximum number of simultaneously running WAL sender processes."), NULL }, &max_wal_senders, 10, 0, MAX_BACKENDS, - NULL, NULL, NULL + check_max_wal_senders, NULL, NULL }, { @@ -10911,7 +10911,7 @@ static bool check_maxconnections(int *newval, void **extra, GucSource source) { if (*newval + autovacuum_max_workers + 1 + - max_worker_processes > MAX_BACKENDS) + max_worker_processes + max_wal_senders > MAX_BACKENDS) return false; return true; } @@ -10919,7 +10919,17 @@ check_maxconnections(int *newval, void **extra, GucSource source) static bool check_autovacuum_max_workers(int *newval, void **extra, GucSource source) { - if (MaxConnections + *newval + 1 + max_worker_processes > MAX_BACKENDS) + if (MaxConnections + *newval + 1 + + max_worker_processes + max_wal_senders > MAX_BACKENDS) + return false; + return true; +} + +static bool +check_max_wal_senders(int *newval, void **extra, GucSource source) +{ + if (MaxConnections + autovacuum_max_workers + 1 + + max_worker_processes + *newval > MAX_BACKENDS) return false; return true; } @@ -10950,7 +10960,8 @@ check_autovacuum_work_mem(int *newval, void **extra, GucSource source) static bool check_max_worker_processes(int *newval, void **extra, GucSource source) { - if (MaxConnections + autovacuum_max_workers + 1 + *newval > MAX_BACKENDS) + if (MaxConnections + autovacuum_max_workers + 1 + + *newval + max_wal_senders > MAX_BACKENDS) return false; return true; } diff --git a/src/bin/pg_controldata/pg_controldata.c b/src/bin/pg_controldata/pg_controldata.c index 1e1fd85b0ba..1aa1db218ac 100644 --- a/src/bin/pg_controldata/pg_controldata.c +++ b/src/bin/pg_controldata/pg_controldata.c @@ -304,6 +304,8 @@ main(int argc, char *argv[]) ControlFile->MaxConnections); printf(_("max_worker_processes setting: %d\n"), ControlFile->max_worker_processes); + printf(_("max_wal_senders setting: %d\n"), + ControlFile->max_wal_senders); printf(_("max_prepared_xacts setting: %d\n"), ControlFile->max_prepared_xacts); printf(_("max_locks_per_xact setting: %d\n"), diff --git a/src/bin/pg_resetwal/pg_resetwal.c b/src/bin/pg_resetwal/pg_resetwal.c index 562c27904f0..2af87132166 100644 --- a/src/bin/pg_resetwal/pg_resetwal.c +++ b/src/bin/pg_resetwal/pg_resetwal.c @@ -728,6 +728,7 @@ GuessControlValues(void) ControlFile.wal_log_hints = false; ControlFile.track_commit_timestamp = false; ControlFile.MaxConnections = 100; + ControlFile.max_wal_senders = 10; ControlFile.max_worker_processes = 8; ControlFile.max_prepared_xacts = 0; ControlFile.max_locks_per_xact = 64; @@ -955,6 +956,7 @@ RewriteControlFile(void) ControlFile.wal_log_hints = false; ControlFile.track_commit_timestamp = false; ControlFile.MaxConnections = 100; + ControlFile.max_wal_senders = 10; ControlFile.max_worker_processes = 8; ControlFile.max_prepared_xacts = 0; ControlFile.max_locks_per_xact = 64; diff --git a/src/include/access/xlog_internal.h b/src/include/access/xlog_internal.h index 3c860372515..42d1065d1e0 100644 --- a/src/include/access/xlog_internal.h +++ b/src/include/access/xlog_internal.h @@ -31,7 +31,7 @@ /* * Each page of XLOG file has a header like this: */ -#define XLOG_PAGE_MAGIC 0xD098 /* can be used as WAL version indicator */ +#define XLOG_PAGE_MAGIC 0xD099 /* can be used as WAL version indicator */ typedef struct XLogPageHeaderData { @@ -226,6 +226,7 @@ typedef struct xl_parameter_change { int MaxConnections; int max_worker_processes; + int max_wal_senders; int max_prepared_xacts; int max_locks_per_xact; int wal_level; diff --git a/src/include/catalog/pg_control.h b/src/include/catalog/pg_control.h index a4aa83bae8f..a3910a5f997 100644 --- a/src/include/catalog/pg_control.h +++ b/src/include/catalog/pg_control.h @@ -21,7 +21,7 @@ /* Version identifier for this pg_control format */ -#define PG_CONTROL_VERSION 1100 +#define PG_CONTROL_VERSION 1200 /* Nonce key length, see below */ #define MOCK_AUTH_NONCE_LEN 32 @@ -177,6 +177,7 @@ typedef struct ControlFileData bool wal_log_hints; int MaxConnections; int max_worker_processes; + int max_wal_senders; int max_prepared_xacts; int max_locks_per_xact; bool track_commit_timestamp; diff --git a/src/include/storage/proc.h b/src/include/storage/proc.h index d203acbb30b..1cee7db89df 100644 --- a/src/include/storage/proc.h +++ b/src/include/storage/proc.h @@ -255,6 +255,8 @@ typedef struct PROC_HDR PGPROC *autovacFreeProcs; /* Head of list of bgworker free PGPROC structures */ PGPROC *bgworkerFreeProcs; + /* Head of list of walsender free PGPROC structures */ + PGPROC *walsenderFreeProcs; /* First pgproc waiting for group XID clear */ pg_atomic_uint32 procArrayGroupFirst; /* First pgproc waiting for group transaction status update */ |