&wait_event_types;
<para>
- Here is an example of how wait events can be viewed:
+ Here are examples of how wait events can be viewed:
<programlisting>
SELECT pid, wait_event_type, wait_event FROM pg_stat_activity WHERE wait_event is NOT NULL;
2540 | Lock | relation
6644 | LWLock | ProcArray
(2 rows)
+</programlisting>
+
+<programlisting>
+SELECT a.pid, a.wait_event, w.description
+ FROM pg_stat_activity a JOIN
+ pg_wait_events w ON (a.wait_event_type = w.type AND
+ a.wait_event = w.name)
+ WHERE wait_event is NOT NULL and a.state = 'active';
+-[ RECORD 1 ]------------------------------------------------------------------
+pid | 686674
+wait_event | WALInitSync
+description | Waiting for a newly initialized WAL file to reach durable storage
</programlisting>
</para>
<entry>views</entry>
</row>
+ <row>
+ <entry><link linkend="view-pg-wait-events"><structname>pg_wait_events</structname></link></entry>
+ <entry>wait events</entry>
+ </row>
+
</tbody>
</tgroup>
</table>
</table>
</sect1>
+
+ <sect1 id="view-pg-wait-events">
+ <title><structname>pg_wait_events</structname></title>
+
+ <indexterm zone="view-pg-wait-events">
+ <primary>pg_wait_events</primary>
+ </indexterm>
+
+ <para>
+ The view <structname>pg_wait_events</structname> provides description about the
+ wait events.
+ </para>
+
+ <table>
+ <title><structname>pg_wait_events</structname> Columns</title>
+ <tgroup cols="1">
+ <thead>
+ <row>
+ <entry role="catalog_table_entry"><para role="column_definition">
+ Column Type
+ </para>
+ <para>
+ Description
+ </para></entry>
+ </row>
+ </thead>
+
+ <tbody>
+ <row>
+ <entry role="catalog_table_entry"><para role="column_definition">
+ <structfield>type</structfield> <type>text</type>
+ </para>
+ <para>
+ Wait event type
+ </para></entry>
+ </row>
+
+ <row>
+ <entry role="catalog_table_entry"><para role="column_definition">
+ <structfield>name</structfield> <type>text</type>
+ </para>
+ <para>
+ Wait event name
+ </para></entry>
+ </row>
+
+ <row>
+ <entry role="catalog_table_entry"><para role="column_definition">
+ <structfield>description</structfield> <type>text</type>
+ </para>
+ <para>
+ Wait event description
+ </para></entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+ </sect1>
+
</chapter>
$(MAKE) -C storage/lmgr lwlocknames.h lwlocknames.c
utils/activity/wait_event_types.h: utils/activity/generate-wait_event_types.pl utils/activity/wait_event_names.txt
- $(MAKE) -C utils/activity wait_event_types.h pgstat_wait_event.c
+ $(MAKE) -C utils/activity wait_event_types.h pgstat_wait_event.c wait_event_funcs_data.c
# run this unconditionally to avoid needing to know its dependencies here:
submake-catalog-headers:
storage/lmgr/lwlocknames.c \
storage/lmgr/lwlocknames.h \
utils/activity/pgstat_wait_event.c \
+ utils/activity/wait_event_funcs_data.c \
utils/activity/wait_event_types.h \
utils/adt/jsonpath_gram.c \
utils/adt/jsonpath_gram.h \
ss.stats_reset
FROM pg_subscription as s,
pg_stat_get_subscription_stats(s.oid) as ss;
+
+CREATE VIEW pg_wait_events AS
+ SELECT * FROM pg_get_wait_events();
/pgstat_wait_event.c
/wait_event_types.h
+/wait_event_funcs_data.c
pgstat_subscription.o \
pgstat_wal.o \
pgstat_xact.o \
- wait_event.o
+ wait_event.o \
+ wait_event_funcs.o
include $(top_srcdir)/src/backend/common.mk
+wait_event_funcs.o: wait_event_funcs_data.c
+wait_event_funcs_data.c: wait_event_types.h
+
wait_event.o: pgstat_wait_event.c
pgstat_wait_event.c: wait_event_types.h
touch $@
$(PERL) $(srcdir)/generate-wait_event_types.pl --code $<
maintainer-clean: clean
- rm -f wait_event_types.h pgstat_wait_event.c
+ rm -f wait_event_types.h pgstat_wait_event.c wait_event_funcs_data.c
# Generate wait events support files from wait_event_names.txt:
# - wait_event_types.h (if --code is passed)
# - pgstat_wait_event.c (if --code is passed)
+# - wait_event_funcs_data.c (if --code is passed)
# - wait_event_types.sgml (if --docs is passed)
#
# Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
# multiple times.
my $htmp = "$output_path/wait_event_types.h.tmp$$";
my $ctmp = "$output_path/pgstat_wait_event.c.tmp$$";
+ my $wctmp = "$output_path/wait_event_funcs_data.c.tmp$$";
open my $h, '>', $htmp or die "Could not open $htmp: $!";
open my $c, '>', $ctmp or die "Could not open $ctmp: $!";
+ open my $wc, '>', $wctmp or die "Could not open $wctmp: $!";
my $header_comment =
'/*-------------------------------------------------------------------------
printf $c $header_comment, 'pgstat_wait_event.c';
+ printf $wc $header_comment, 'wait_event_funcs_data.c';
+
+ # Generate the pgstat_wait_event.c and wait_event_types.h files
# uc() is being used to force the comparison to be case-insensitive.
foreach my $waitclass (sort { uc($a) cmp uc($b) } keys %hashwe)
{
-
- # Don't generate .c and .h files for Extension, LWLock and
- # Lock, these are handled independently.
+ # Don't generate the pgstat_wait_event.c and wait_event_types.h files
+ # for Extension, LWLock and Lock, these are handled independently.
next
if ( $waitclass eq 'WaitEventExtension'
|| $waitclass eq 'WaitEventLWLock'
printf $c "}\n\n";
}
+ # Generate wait_event_funcs_data.c, building the contents of a static
+ # C structure holding all the information about the wait events.
+ # uc() is being used to force the comparison to be case-insensitive,
+ # even though it is not required here.
+ foreach my $waitclass (sort { uc($a) cmp uc($b) } keys %hashwe)
+ {
+ my $last = $waitclass;
+ $last =~ s/^WaitEvent//;
+
+ foreach my $wev (@{ $hashwe{$waitclass} })
+ {
+ my $new_desc = substr $wev->[2], 1, -2;
+ # Escape single quotes.
+ $new_desc =~ s/'/\\'/g;
+
+ # Replace the "quote" markups by real ones.
+ $new_desc =~ s/<quote>(.*?)<\/quote>/\\"$1\\"/g;
+
+ # Remove SGML markups.
+ $new_desc =~ s/<.*?>(.*?)<.*?>/$1/g;
+
+ # Tweak contents about links <xref linkend="text"/>
+ # on GUCs,
+ while (my ($capture) =
+ $new_desc =~ m/<xref linkend="guc-(.*?)"\/>/g)
+ {
+ $capture =~ s/-/_/g;
+ $new_desc =~ s/<xref linkend="guc-.*?"\/>/$capture/g;
+ }
+ # Then remove any reference to
+ # "see <xref linkend="text"/>".
+ $new_desc =~ s/; see.*$//;
+
+ # Build one element of the C structure holding the
+ # wait event info, as of (type, name, description).
+ printf $wc "\t{\"%s\", \"%s\", \"%s\"},\n", $last, $wev->[1],
+ $new_desc;
+ }
+ }
+
printf $h "#endif /* WAIT_EVENT_TYPES_H */\n";
close $h;
close $c;
+ close $wc;
rename($htmp, "$output_path/wait_event_types.h")
|| die "rename: $htmp to $output_path/wait_event_types.h: $!";
rename($ctmp, "$output_path/pgstat_wait_event.c")
|| die "rename: $ctmp to $output_path/pgstat_wait_event.c: $!";
+ rename($wctmp, "$output_path/wait_event_funcs_data.c")
+ || die "rename: $wctmp to $output_path/wait_event_funcs_data.c: $!";
}
# Generate the .sgml file.
elsif ($gen_docs)
Options:
--outdir Output directory (default '.')
- --code Generate wait_event_types.h and pgstat_wait_event.c.
+ --code Generate C and header files.
--sgml Generate wait_event_types.sgml.
generate-wait_event_types.pl generates the SGML documentation and code
# seems nicer to not add that as an include path for the whole backend.
waitevent_sources = files(
'wait_event.c',
+ 'wait_event_funcs.c',
)
wait_event = static_library('wait_event_names',
}
+/*
+ * Returns a list of currently defined custom wait event names for extensions.
+ * The result is a palloc'd array, with the number of elements saved in
+ * *nwaitevents.
+ */
+char **
+GetWaitEventExtensionNames(int *nwaitevents)
+{
+ char **waiteventnames;
+ WaitEventExtensionEntryByName *hentry;
+ HASH_SEQ_STATUS hash_seq;
+ int index;
+ int els;
+
+ LWLockAcquire(WaitEventExtensionLock, LW_SHARED);
+
+ /* Now we can safely count the number of entries */
+ els = hash_get_num_entries(WaitEventExtensionHashByName);
+
+ /* Allocate enough space for all entries */
+ waiteventnames = palloc(els * sizeof(char *));
+
+ /* Now scan the hash table to copy the data */
+ hash_seq_init(&hash_seq, WaitEventExtensionHashByName);
+
+ index = 0;
+ while ((hentry = (WaitEventExtensionEntryByName *) hash_seq_search(&hash_seq)) != NULL)
+ {
+ waiteventnames[index] = pstrdup(hentry->wait_event_name);
+ index++;
+ }
+
+ LWLockRelease(WaitEventExtensionLock);
+
+ Assert(index == els);
+
+ *nwaitevents = index;
+ return waiteventnames;
+}
+
/*
* Configure wait event reporting to report wait events to *wait_event_info.
* *wait_event_info needs to be valid until pgstat_reset_wait_event_storage()
--- /dev/null
+/*------------------------------------------------------------------------
+ *
+ * wait_event_funcs.c
+ * Functions for accessing wait event data.
+ *
+ * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ *
+ * IDENTIFICATION
+ * src/backend/utils/activity/wait_event_funcs.c
+ *
+ *------------------------------------------------------------------------
+ */
+#include "postgres.h"
+
+#include "funcapi.h"
+#include "utils/builtins.h"
+#include "utils/wait_event.h"
+
+/*
+ * Each wait event has one corresponding entry in this structure, fed to
+ * the SQL function of this file.
+ */
+static const struct
+{
+ const char *type;
+ const char *name;
+ const char *description;
+}
+
+ waitEventData[] =
+{
+#include "wait_event_funcs_data.c"
+ /* end of list */
+ {NULL, NULL, NULL}
+};
+
+
+/*
+ * pg_get_wait_events
+ *
+ * List information about wait events (type, name and description).
+ */
+Datum
+pg_get_wait_events(PG_FUNCTION_ARGS)
+{
+#define PG_GET_WAIT_EVENTS_COLS 3
+ ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
+ char **waiteventnames;
+ int nbextwaitevents;
+
+ /* Build tuplestore to hold the result rows */
+ InitMaterializedSRF(fcinfo, 0);
+
+ /* Iterate over the list of wait events */
+ for (int idx = 0; waitEventData[idx].type != NULL; idx++)
+ {
+ Datum values[PG_GET_WAIT_EVENTS_COLS] = {0};
+ bool nulls[PG_GET_WAIT_EVENTS_COLS] = {0};
+
+ values[0] = CStringGetTextDatum(waitEventData[idx].type);
+ values[1] = CStringGetTextDatum(waitEventData[idx].name);
+ values[2] = CStringGetTextDatum(waitEventData[idx].description);
+
+ tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
+ }
+
+ /* Handle custom wait events for extensions */
+ waiteventnames = GetWaitEventExtensionNames(&nbextwaitevents);
+
+ for (int idx = 0; idx < nbextwaitevents; idx++)
+ {
+ StringInfoData buf;
+ Datum values[PG_GET_WAIT_EVENTS_COLS] = {0};
+ bool nulls[PG_GET_WAIT_EVENTS_COLS] = {0};
+
+
+ values[0] = CStringGetTextDatum("Extension");
+ values[1] = CStringGetTextDatum(waiteventnames[idx]);
+
+ initStringInfo(&buf);
+ appendStringInfo(&buf,
+ "Waiting for custom wait event \"%s\" defined by extension module",
+ waiteventnames[idx]);
+
+ values[2] = CStringGetTextDatum(buf.data);
+
+ tuplestore_putvalues(rsinfo->setResult, rsinfo->setDesc, values, nulls);
+ }
+
+ return (Datum) 0;
+}
proargmodes => '{i,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o,o}',
proargnames => '{pid,datid,pid,usesysid,application_name,state,query,wait_event_type,wait_event,xact_start,query_start,backend_start,state_change,client_addr,client_hostname,client_port,backend_xid,backend_xmin,backend_type,ssl,sslversion,sslcipher,sslbits,ssl_client_dn,ssl_client_serial,ssl_issuer_dn,gss_auth,gss_princ,gss_enc,gss_delegation,leader_pid,query_id}',
prosrc => 'pg_stat_get_activity' },
+{ oid => '8403', descr => 'describe wait events',
+ proname => 'pg_get_wait_events', procost => '10', prorows => '250',
+ proretset => 't', provolatile => 'v', prorettype => 'record',
+ proargtypes => '', proallargtypes => '{text,text,text}',
+ proargmodes => '{o,o,o}', proargnames => '{type,name,description}',
+ prosrc => 'pg_get_wait_events' },
{ oid => '3318',
descr => 'statistics: information about progress of backends running maintenance command',
proname => 'pg_stat_get_progress_info', prorows => '100', proretset => 't',
# Copyright (c) 2022-2023, PostgreSQL Global Development Group
-wait_event_output = ['wait_event_types.h', 'pgstat_wait_event.c']
+wait_event_output = ['wait_event_types.h', 'pgstat_wait_event.c', 'wait_event_funcs_data.c']
wait_event_target = custom_target('wait_event_names',
input: files('../../backend/utils/activity/wait_event_names.txt'),
output: wait_event_output,
],
build_by_default: true,
install: true,
- install_dir: [dir_include_server / 'utils', false],
+ install_dir: [dir_include_server / 'utils', false, false],
)
wait_event_types_h = wait_event_target[0]
extern Size WaitEventExtensionShmemSize(void);
extern uint32 WaitEventExtensionNew(const char *wait_event_name);
+extern char **GetWaitEventExtensionNames(int *nwaitevents);
/* ----------
* pgstat_report_wait_start() -
is($result, 1,
'dynamic bgworker has reported "worker_spi_main" as wait event');
+# Check the wait event used by the dynamic bgworker appears in pg_wait_events
+$result = $node->safe_psql('postgres',
+ q[SELECT count(*) > 0 from pg_wait_events where type = 'Extension' and name = 'worker_spi_main';]
+);
+is($result, 't', '"worker_spi_main" is reported in pg_wait_events');
+
note "testing bgworkers loaded with shared_preload_libraries";
# Create the database first so as the workers can connect to it when
FROM (pg_class c
LEFT JOIN pg_namespace n ON ((n.oid = c.relnamespace)))
WHERE (c.relkind = 'v'::"char");
+pg_wait_events| SELECT type,
+ name,
+ description
+ FROM pg_get_wait_events() pg_get_wait_events(type, name, description);
SELECT tablename, rulename, definition FROM pg_rules
WHERE schemaname = 'pg_catalog'
ORDER BY tablename, rulename;
enable_tidscan | on
(21 rows)
+-- There are always wait event descriptions for various types.
+select type, count(*) > 0 as ok FROM pg_wait_events
+ group by type order by type COLLATE "C";
+ type | ok
+-----------+----
+ Activity | t
+ BufferPin | t
+ Client | t
+ Extension | t
+ IO | t
+ IPC | t
+ LWLock | t
+ Lock | t
+ Timeout | t
+(9 rows)
+
-- Test that the pg_timezone_names and pg_timezone_abbrevs views are
-- more-or-less working. We can't test their contents in any great detail
-- without the outputs changing anytime IANA updates the underlying data,
-- a regression test run.
select name, setting from pg_settings where name like 'enable%';
+-- There are always wait event descriptions for various types.
+select type, count(*) > 0 as ok FROM pg_wait_events
+ group by type order by type COLLATE "C";
+
-- Test that the pg_timezone_names and pg_timezone_abbrevs views are
-- more-or-less working. We can't test their contents in any great detail
-- without the outputs changing anytime IANA updates the underlying data,
'src/include/utils/wait_event_types.h',
'src/backend/utils/activity/wait_event_names.txt'))
{
- print "Generating pgstat_wait_event.c and wait_event_types.h...\n";
+ print
+ "Generating pgstat_wait_event.c, wait_event_types.h and wait_event_funcs_data.c...\n";
my $activ = 'src/backend/utils/activity';
system(
"perl $activ/generate-wait_event_types.pl --outdir $activ --code $activ/wait_event_names.txt"
if exist doc\src\sgml\version.sgml del /q doc\src\sgml\version.sgml
if %DIST%==1 if exist src\backend\utils\activity\pgstat_wait_event.c del /q src\backend\utils\activity\pgstat_wait_event.c
+if %DIST%==1 if exist src\backend\utils\activity\wait_event_funcs_data.c del /q src\backend\utils\activity\wait_event_funcs_data.c
if %DIST%==1 if exist src\backend\utils\activity\wait_event_types.h del /q src\backend\utils\activity\wait_event_types.h
if %DIST%==1 if exist src\backend\utils\fmgroids.h del /q src\backend\utils\fmgroids.h
if %DIST%==1 if exist src\backend\utils\fmgrprotos.h del /q src\backend\utils\fmgrprotos.h
projects / postgresql.git / commitdiff