diff options
| -rw-r--r-- | doc/src/sgml/glossary.sgml | 118 | ||||
| -rw-r--r-- | src/include/miscadmin.h | 2 |
2 files changed, 106 insertions, 14 deletions
diff --git a/doc/src/sgml/glossary.sgml b/doc/src/sgml/glossary.sgml index 63ff4bbdf06..0c88988fa66 100644 --- a/doc/src/sgml/glossary.sgml +++ b/doc/src/sgml/glossary.sgml @@ -48,7 +48,7 @@ <glossterm>Analyze (operation)</glossterm> <glossdef> <para> - The process of collecting statistics from data in + The act of collecting statistics from data in <glossterm linkend="glossary-table">tables</glossterm> and other <glossterm linkend="glossary-relation">relations</glossterm> to help the <glossterm linkend="glossary-planner">query planner</glossterm> @@ -113,8 +113,12 @@ <para> A set of background processes that routinely perform <glossterm linkend="glossary-vacuum">vacuum</glossterm> - and <glossterm linkend="glossary-analyze">analyze</glossterm> - operations. + and <glossterm linkend="glossary-analyze">analyze</glossterm> operations. + The <glossterm linkend="glossary-auxiliary-proc">auxiliary process</glossterm> + that coordinates the work and is always present (unless autovacuum + is disabled) is known as the <firstterm>autovacuum launcher</firstterm>, + and the processes that carry out the tasks are known as the + <firstterm>autovacuum workers</firstterm>. </para> <para> For more information, see @@ -123,6 +127,34 @@ </glossdef> </glossentry> + <glossentry id="glossary-auxiliary-proc"> + <glossterm>Auxiliary process</glossterm> + <glossdef> + <para> + A process within an <glossterm linkend="glossary-instance">instance</glossterm> + that is in charge of some specific background task for the instance. + The auxiliary processes consist of <!-- in alphabetical order --> + <!-- NB: In the code, the autovac launcher doesn't use the auxiliary + process scaffolding; however it does behave as one so we list it + here anyway. In addition, logger and stats collector aren't + connected to shared memory so most code outside postmaster.c + doesn't even consider them "procs" in the first place. + --> + the <glossterm linkend="glossary-autovacuum">autovacuum launcher</glossterm> + (but not the autovacuum workers), + the <glossterm linkend="glossary-background-writer">background writer</glossterm>, + the <glossterm linkend="glossary-checkpointer">checkpointer</glossterm>, + the <glossterm linkend="glossary-logger">logger</glossterm>, + the <glossterm linkend="glossary-startup-process">startup process</glossterm>, + the <glossterm linkend="glossary-stats-collector">statistics collector</glossterm>, + the <glossterm linkend="glossary-wal-archiver">WAL archiver</glossterm>, + the <glossterm linkend="glossary-wal-receiver">WAL receiver</glossterm> + (but not the <glossterm linkend="glossary-wal-sender">WAL senders</glossterm>), + and the <glossterm linkend="glossary-wal-writer">WAL writer</glossterm>. + </para> + </glossdef> + </glossentry> + <glossentry id="glossary-backend"> <glossterm>Backend (process)</glossterm> <glossdef> @@ -163,7 +195,8 @@ <glossterm>Background writer (process)</glossterm> <glossdef> <para> - A process that writes dirty + An <glossterm linkend="glossary-auxiliary-proc">auxiliary process</glossterm> + that writes dirty <glossterm linkend="glossary-data-page">data pages</glossterm> from <glossterm linkend="glossary-shared-memory">shared memory</glossterm> to the file system. It wakes up periodically, but works only for a short @@ -285,7 +318,9 @@ <glossterm>Checkpointer (process)</glossterm> <glossdef> <para> - A specialized process responsible for executing checkpoints. + An <glossterm linkend="glossary-auxiliary-proc">auxiliary process</glossterm> + that is responsible for executing + <glossterm linkend="glossary-checkpoint">checkpoints</glossterm>. </para> </glossdef> </glossentry> @@ -778,8 +813,9 @@ <glossterm>Instance</glossterm> <glossdef> <para> - A group of backend and auxiliary processes that communicate using - a common shared memory area. One + A group of <glossterm linkend="glossary-backend">backend</glossterm> and + <glossterm linkend="glossary-auxiliary-proc">auxiliary processes</glossterm> + that communicate using a common shared memory area. One <glossterm linkend="glossary-postmaster">postmaster process</glossterm> manages the instance; one instance manages exactly one <glossterm linkend="glossary-db-cluster">database cluster</glossterm> @@ -881,8 +917,8 @@ <glossterm>Logger (process)</glossterm> <glossdef> <para> - If activated, the process - writes information about database events into the current + An <glossterm linkend="glossary-auxiliary-proc">auxiliary process</glossterm> + which, if enabled, writes information about database events into the current <glossterm linkend="glossary-log-file">log file</glossterm>. When reaching certain time- or volume-dependent criteria, a new log file is created. @@ -1040,8 +1076,9 @@ <glossdef> <para> The very first process of an <glossterm linkend="glossary-instance">instance</glossterm>. - It starts and manages the other auxiliary processes and creates - <glossterm linkend="glossary-backend">backend processes</glossterm> + It starts and manages the + <glossterm linkend="glossary-auxiliary-proc">auxiliary processes</glossterm> + and creates <glossterm linkend="glossary-backend">backend processes</glossterm> on demand. </para> <para> @@ -1452,6 +1489,22 @@ </glossdef> </glossentry> + <glossentry id="glossary-startup-process"> + <glossterm>Startup process</glossterm> + <glossdef> + <para> + An <glossterm linkend="glossary-auxiliary-proc">auxiliary process</glossterm> + that replays WAL during crash recovery and in a + <glossterm linkend="glossary-replication">physical replica</glossterm>. + </para> + <para> + (The name is historical: the startup process was named before + replication was implemented; the name refers to its task as it + relates to the server startup following a crash.) + </para> + </glossdef> + </glossentry> + <glossentry id="glossary-sql-object"> <glossterm>SQL object</glossterm> <glossdef> @@ -1514,8 +1567,10 @@ <glossterm>Stats collector (process)</glossterm> <glossdef> <para> - This process collects statistical information about the - <glossterm linkend="glossary-instance">instance</glossterm>'s activities. + An <glossterm linkend="glossary-auxiliary-proc">auxiliary process</glossterm> + which, if enabled, receives statistical information + about the <glossterm linkend="glossary-instance">instance</glossterm>'s + activities. </para> <para> For more information, see @@ -1856,7 +1911,9 @@ <glossterm>WAL archiver (process)</glossterm> <glossdef> <para> - A process that saves copies of <glossterm linkend="glossary-wal-file">WAL files</glossterm> + An <glossterm linkend="glossary-auxiliary-proc">auxiliary process</glossterm> + which, if enabled, saves copies of + <glossterm linkend="glossary-wal-file">WAL files</glossterm> for the purpose of creating backups or keeping <glossterm linkend="glossary-replica">replicas</glossterm> current. </para> @@ -1914,11 +1971,44 @@ </glossdef> </glossentry> + <glossentry id="glossary-wal-receiver"> + <glossterm>WAL receiver</glossterm> + <glossdef> + <para> + An <glossterm linkend="glossary-auxiliary-proc">auxiliary process</glossterm> + that runs on a <glossterm linkend="glossary-replica">replica</glossterm> + to receive WAL from the + <glossterm linkend="glossary-primary-server">primary server</glossterm> + for replay by the + <glossterm linkend="glossary-startup-process">startup process</glossterm>. + </para> + + <para> + For more information, see + <xref linkend="warm-standby"/>. + </para> + </glossdef> + </glossentry> + <glossentry> <glossterm>WAL segment</glossterm> <glosssee otherterm="glossary-wal-file" /> </glossentry> + <glossentry id="glossary-wal-sender"> + <glossterm>WAL sender (process)</glossterm> + <glossdef> + <para> + A special <glossterm linkend="glossary-backend">backend process</glossterm> + that streams WAL over a network. The receiving end can be a + <glossterm linkend="glossary-wal-receiver">WAL receiver</glossterm> + in a <glossterm linkend="glossary-replica">replica</glossterm>, + <xref linkend="app-pgreceivewal"/>, or any other client program + that speaks the replication protocol. + </para> + </glossdef> + </glossentry> + <glossentry id="glossary-wal-writer"> <glossterm>WAL writer (process)</glossterm> <glossdef> diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h index 2e2e9a364a7..90a30160657 100644 --- a/src/include/miscadmin.h +++ b/src/include/miscadmin.h @@ -422,6 +422,8 @@ extern ProcessingMode Mode; * Auxiliary-process type identifiers. These used to be in bootstrap.h * but it seems saner to have them here, with the ProcessingMode stuff. * The MyAuxProcType global is defined and set in auxprocess.c. + * + * Make sure to list in the glossary any items you add here. */ typedef enum |