diff options
| -rw-r--r-- | doc/src/sgml/config.sgml | 28 | ||||
| -rw-r--r-- | src/backend/utils/misc/guc_tables.c | 10 |
2 files changed, 18 insertions, 20 deletions
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index 25111d5caf3..27622904654 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -10236,13 +10236,12 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' </term> <listitem> <para> - The shared lock table tracks locks on - <varname>max_locks_per_transaction</varname> * (<xref - linkend="guc-max-connections"/> + <xref - linkend="guc-max-prepared-transactions"/>) objects (e.g., tables); + The shared lock table has space for + <varname>max_locks_per_transaction</varname> objects + (e.g., tables) per server process or prepared transaction; hence, no more than this many distinct objects can be locked at - any one time. This parameter controls the average number of object - locks allocated for each transaction; individual transactions + any one time. This parameter limits the average number of object + locks used by each transaction; individual transactions can lock more objects as long as the locks of all transactions fit in the lock table. This is <emphasis>not</emphasis> the number of rows that can be locked; that value is unlimited. The default, @@ -10253,8 +10252,8 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' </para> <para> - When running a standby server, you must set this parameter to the - same or higher value than on the primary server. Otherwise, queries + When running a standby server, you must set this parameter to have the + same or higher value as on the primary server. Otherwise, queries will not be allowed in the standby server. </para> </listitem> @@ -10268,17 +10267,16 @@ dynamic_library_path = 'C:\tools\postgresql;H:\my_project\lib;$libdir' </term> <listitem> <para> - The shared predicate lock table tracks locks on - <varname>max_pred_locks_per_transaction</varname> * (<xref - linkend="guc-max-connections"/> + <xref - linkend="guc-max-prepared-transactions"/>) objects (e.g., tables); + The shared predicate lock table has space for + <varname>max_pred_locks_per_transaction</varname> objects + (e.g., tables) per server process or prepared transaction; hence, no more than this many distinct objects can be locked at - any one time. This parameter controls the average number of object - locks allocated for each transaction; individual transactions + any one time. This parameter limits the average number of object + locks used by each transaction; individual transactions can lock more objects as long as the locks of all transactions fit in the lock table. This is <emphasis>not</emphasis> the number of rows that can be locked; that value is unlimited. The default, - 64, has generally been sufficient in testing, but you might need to + 64, has historically proven sufficient, but you might need to raise this value if you have clients that touch many different tables in a single serializable transaction. This parameter can only be set at server start. diff --git a/src/backend/utils/misc/guc_tables.c b/src/backend/utils/misc/guc_tables.c index e8e8245e91f..cf7f465ddb1 100644 --- a/src/backend/utils/misc/guc_tables.c +++ b/src/backend/utils/misc/guc_tables.c @@ -2599,9 +2599,9 @@ struct config_int ConfigureNamesInt[] = { {"max_locks_per_transaction", PGC_POSTMASTER, LOCK_MANAGEMENT, gettext_noop("Sets the maximum number of locks per transaction."), - gettext_noop("The shared lock table is sized on the assumption that " - "at most max_locks_per_transaction * max_connections distinct " - "objects will need to be locked at any one time.") + gettext_noop("The shared lock table is sized on the assumption that at most " + "max_locks_per_transaction objects per server process or prepared " + "transaction will need to be locked at any one time.") }, &max_locks_per_xact, 64, 10, INT_MAX, @@ -2612,8 +2612,8 @@ struct config_int ConfigureNamesInt[] = {"max_pred_locks_per_transaction", PGC_POSTMASTER, LOCK_MANAGEMENT, gettext_noop("Sets the maximum number of predicate locks per transaction."), gettext_noop("The shared predicate lock table is sized on the assumption that " - "at most max_pred_locks_per_transaction * max_connections distinct " - "objects will need to be locked at any one time.") + "at most max_pred_locks_per_transaction objects per server process " + "or prepared transaction will need to be locked at any one time.") }, &max_predicate_locks_per_xact, 64, 10, INT_MAX, |