From cd171da2150e1ee8cfc6ca4bdee0a591df6f566b Mon Sep 17 00:00:00 2001 From: Justin Pryzby Date: Mon, 23 Jan 2023 18:33:51 -0600 Subject: [PATCH v5] add pg_huge_pages_active() This is useful to show the current state of huge pages when huge_pages=try. The effective status is not otherwise visible without OS level tools like gdb or /proc/N/smaps. https://www.postgresql.org/message-id/flat/TU4PR8401MB1152EBB0D271F827E2E37A01EECC9@TU4PR8401MB1152.NAMPRD84.PROD.OUTLOOK.COM --- doc/src/sgml/config.sgml | 3 ++- doc/src/sgml/func.sgml | 14 ++++++++++++++ src/backend/port/sysv_shmem.c | 2 ++ src/backend/port/win32_shmem.c | 2 ++ src/backend/utils/adt/misc.c | 11 +++++++++++ src/include/catalog/pg_proc.dat | 5 +++++ src/include/miscadmin.h | 3 +++ 7 files changed, 39 insertions(+), 1 deletion(-) diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml index e5c41cc6c6d..d66f73a494a 100644 --- a/doc/src/sgml/config.sgml +++ b/doc/src/sgml/config.sgml @@ -1700,23 +1700,24 @@ include_dir 'conf.d' Controls whether huge pages are requested for the main shared memory area. Valid values are try (the default), on, and off. With huge_pages set to try, the server will try to request huge pages, but fall back to the default if that fails. With on, failure to request huge pages will prevent the server from starting up. With off, - huge pages will not be requested. + huge pages will not be requested. The actual state of huge pages is + indicated by pg_huge_pages_active(). At present, this setting is supported only on Linux and Windows. The setting is ignored on other systems when set to try. On Linux, it is only supported when shared_memory_type is set to mmap (the default). diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml index a5bf2f01b57..4e99d5aff5c 100644 --- a/doc/src/sgml/func.sgml +++ b/doc/src/sgml/func.sgml @@ -22516,22 +22516,36 @@ SELECT * FROM pg_ls_dir('.') WITH ORDINALITY AS t(ls,n); To request information about a specific log file format, supply either csvlog, jsonlog or stderr as the value of the optional parameter. The result is NULL if the log format requested is not configured in . The result reflects the contents of the current_logfiles file. + + + + pg_huge_pages_active + + pg_huge_pages_active () + bool + + + Reports whether huge pages are in use by the current instance. + See for more information. + + + pg_my_temp_schema pg_my_temp_schema () oid Returns the OID of the current session's temporary schema, or zero if it has none (because it has not created any temporary tables). diff --git a/src/backend/port/sysv_shmem.c b/src/backend/port/sysv_shmem.c index eaba244bc9c..9ff2d7b3d38 100644 --- a/src/backend/port/sysv_shmem.c +++ b/src/backend/port/sysv_shmem.c @@ -619,22 +619,24 @@ CreateAnonymousSegment(Size *size) allocsize += hugepagesize - (allocsize % hugepagesize); ptr = mmap(NULL, allocsize, PROT_READ | PROT_WRITE, PG_MMAP_FLAGS | mmap_flags, -1, 0); mmap_errno = errno; if (huge_pages == HUGE_PAGES_TRY && ptr == MAP_FAILED) elog(DEBUG1, "mmap(%zu) with MAP_HUGETLB failed, huge pages disabled: %m", allocsize); } #endif + huge_pages_active = (ptr != MAP_FAILED); + if (ptr == MAP_FAILED && huge_pages != HUGE_PAGES_ON) { /* * Use the original size, not the rounded-up value, when falling back * to non-huge pages. */ allocsize = *size; ptr = mmap(NULL, allocsize, PROT_READ | PROT_WRITE, PG_MMAP_FLAGS, -1, 0); mmap_errno = errno; } diff --git a/src/backend/port/win32_shmem.c b/src/backend/port/win32_shmem.c index 62e08074770..f97971ef340 100644 --- a/src/backend/port/win32_shmem.c +++ b/src/backend/port/win32_shmem.c @@ -319,22 +319,24 @@ retry: * If the segment already existed, CreateFileMapping() will return a * handle to the existing one and set ERROR_ALREADY_EXISTS. */ if (GetLastError() == ERROR_ALREADY_EXISTS) { CloseHandle(hmap); /* Close the handle, since we got a valid one * to the previous segment. */ hmap = NULL; Sleep(1000); continue; } + + huge_pages_active = ((flProtect & SEC_LARGE_PAGES) != 0); break; } /* * If the last call in the loop still returned ERROR_ALREADY_EXISTS, this * shared memory segment exists and we assume it belongs to somebody else. */ if (!hmap) ereport(FATAL, (errmsg("pre-existing shared memory block is still in use"), errhint("Check if there are any old server processes still running, and terminate them."))); diff --git a/src/backend/utils/adt/misc.c b/src/backend/utils/adt/misc.c index 5d78d6dc060..3c175d88c59 100644 --- a/src/backend/utils/adt/misc.c +++ b/src/backend/utils/adt/misc.c @@ -1070,11 +1070,22 @@ pg_get_replica_identity_index(PG_FUNCTION_ARGS) PG_RETURN_NULL(); } /* * Transition function for the ANY_VALUE aggregate */ Datum any_value_transfn(PG_FUNCTION_ARGS) { PG_RETURN_DATUM(PG_GETARG_DATUM(0)); } + +bool huge_pages_active = false; + +/* + * Return status of huge pages. + */ +Datum +pg_huge_pages_active(PG_FUNCTION_ARGS) +{ + PG_RETURN_BOOL(huge_pages_active); +} diff --git a/src/include/catalog/pg_proc.dat b/src/include/catalog/pg_proc.dat index ae658e721fd..7cfa11c994c 100644 --- a/src/include/catalog/pg_proc.dat +++ b/src/include/catalog/pg_proc.dat @@ -1811,22 +1811,27 @@ proname => 'bpchar', prorettype => 'bpchar', proargtypes => 'char', prosrc => 'char_bpchar' }, { oid => '861', descr => 'name of the current database', proname => 'current_database', provolatile => 's', prorettype => 'name', proargtypes => '', prosrc => 'current_database' }, { oid => '817', descr => 'get the currently executing query', proname => 'current_query', proisstrict => 'f', provolatile => 'v', proparallel => 'r', prorettype => 'text', proargtypes => '', prosrc => 'current_query' }, +{ oid => '8218', descr => 'get the state of huge pages', + proname => 'pg_huge_pages_active', proisstrict => 't', provolatile => 's', + proparallel => 's', prorettype => 'bool', proargtypes => '', + prosrc => 'pg_huge_pages_active' }, + { oid => '3399', proname => 'int8_mul_cash', prorettype => 'money', proargtypes => 'int8 money', prosrc => 'int8_mul_cash' }, { oid => '862', proname => 'int4_mul_cash', prorettype => 'money', proargtypes => 'int4 money', prosrc => 'int4_mul_cash' }, { oid => '863', proname => 'int2_mul_cash', prorettype => 'money', proargtypes => 'int2 money', prosrc => 'int2_mul_cash' }, { oid => '3344', proname => 'cash_mul_int8', prorettype => 'money', diff --git a/src/include/miscadmin.h b/src/include/miscadmin.h index 06a86f9ac1f..8169e5bd6dd 100644 --- a/src/include/miscadmin.h +++ b/src/include/miscadmin.h @@ -268,22 +268,25 @@ extern PGDLLIMPORT int VacuumCostPageMiss; extern PGDLLIMPORT int VacuumCostPageDirty; extern PGDLLIMPORT int VacuumCostLimit; extern PGDLLIMPORT double VacuumCostDelay; extern PGDLLIMPORT int64 VacuumPageHit; extern PGDLLIMPORT int64 VacuumPageMiss; extern PGDLLIMPORT int64 VacuumPageDirty; extern PGDLLIMPORT int VacuumCostBalance; extern PGDLLIMPORT bool VacuumCostActive; +/* in adt/misc.c */ +extern PGDLLIMPORT bool huge_pages_active; + /* in tcop/postgres.c */ typedef char *pg_stack_base_t; extern pg_stack_base_t set_stack_base(void); extern void restore_stack_base(pg_stack_base_t base); extern void check_stack_depth(void); extern bool stack_is_too_deep(void); /* in tcop/utility.c */ -- 2.34.1