The cfbot showed issues compiling on linux and windows.
http://cfbot.cputube.org/takashi-menjo.html
https://cirrus-ci.com/task/6125740327436288
[02:30:06.538] In file included from xlog.c:38:
[02:30:06.538] ../../../../src/include/access/xlogpmem.h:32:42: error: unknown
type name ‘tli’
[02:30:06.538] 32 | PmemXLogEnsurePrevMapped(XLogRecPtr ptr, tli)
[02:30:06.538] | ^~~
[02:30:06.538] xlog.c: In function ‘GetXLogBuffer’:
[02:30:06.538] xlog.c:1959:19: warning: implicit declaration of function
‘PmemXLogEnsurePrevMapped’ [-Wimplicit-function-declaration]
[02:30:06.538] 1959 | openLogSegNo = PmemXLogEnsurePrevMapped(endptr, tli);
https://cirrus-ci.com/task/6688690280857600?logs=build#L379
[02:33:25.752] c:\cirrus\src\include\access\xlogpmem.h(33,1): error C2081:
'tli': name in formal parameter list illegal (compiling source file
src/backend/access/transam/xlog.c) [c:\cirrus\postgres.vcxproj]
I'm attaching a probable fix. Unfortunately, for patches like this, most of
the functionality isn't exercised unless the library is installed and
compilation and runtime are enabled by default.
In 0009: recaluculated => recalculated
0010-Update-document should be squished with 0003-Add-wal_pmem_map-to-GUC (and
maybe 0002 and 0001). I believe the patches after 0005 are more WIP, so it's
fine if they're not squished yet. I'm not sure what the point is of this one:
0008-Let-wal_pmem_map-be-constant-unl
+ ereport(ERROR,
+ (errcode_for_file_access(),
+ errmsg("could not pmem_map_file \"%s\": %m",
path)));
=> The outer parenthesis are not needed since e3a87b4.
>From e5614f2ea3ff6aaf016343f81f74366440e18f6f Mon Sep 17 00:00:00 2001
From: Takashi Menjo <takashi.menjou...@hco.ntt.co.jp>
Date: Tue, 23 Mar 2021 13:32:27 +0900
Subject: [PATCH 01/13] Add --with-libpmem option for PMEM support
---
configure | 99 ++++++++++++++++++++++++++++++++++++++
configure.ac | 17 +++++++
src/include/pg_config.h.in | 6 +++
3 files changed, 122 insertions(+)
diff --git a/configure b/configure
index 3b19105328d..22c364fac4f 100755
--- a/configure
+++ b/configure
@@ -699,6 +699,7 @@ with_gnu_ld
LD
LDFLAGS_SL
LDFLAGS_EX
+with_libpmem
LZ4_LIBS
LZ4_CFLAGS
with_lz4
@@ -868,6 +869,7 @@ with_libxslt
with_system_tzdata
with_zlib
with_lz4
+with_libpmem
with_gnu_ld
with_ssl
with_openssl
@@ -1576,6 +1578,7 @@ Optional Packages:
use system time zone data in DIR
--without-zlib do not use Zlib
--with-lz4 build with LZ4 support
+ --with-libpmem build with PMEM support
--with-gnu-ld assume the C compiler uses GNU ld [default=no]
--with-ssl=LIB use LIB for SSL/TLS support (openssl)
--with-openssl obsolete spelling of --with-ssl=openssl
@@ -9033,6 +9036,41 @@ fi
done
fi
+#
+# libpmem
+#
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether to build with PMEM support" >&5
+$as_echo_n "checking whether to build with PMEM support... " >&6; }
+
+
+
+# Check whether --with-libpmem was given.
+if test "${with_libpmem+set}" = set; then :
+ withval=$with_libpmem;
+ case $withval in
+ yes)
+
+$as_echo "#define USE_LIBPMEM 1" >>confdefs.h
+
+ ;;
+ no)
+ :
+ ;;
+ *)
+ as_fn_error $? "no argument expected for --with-libpmem option" "$LINENO" 5
+ ;;
+ esac
+
+else
+ with_libpmem=no
+
+fi
+
+
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $with_libpmem" >&5
+$as_echo "$with_libpmem" >&6; }
+
+
#
# Assignments
#
@@ -13504,6 +13542,56 @@ fi
fi
+if test "$with_libpmem" = yes; then
+ { $as_echo "$as_me:${as_lineno-$LINENO}: checking for pmem_memcpy in -lpmem" >&5
+$as_echo_n "checking for pmem_memcpy in -lpmem... " >&6; }
+if ${ac_cv_lib_pmem_pmem_memcpy+:} false; then :
+ $as_echo_n "(cached) " >&6
+else
+ ac_check_lib_save_LIBS=$LIBS
+LIBS="-lpmem $LIBS"
+cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h. */
+
+/* Override any GCC internal prototype to avoid an error.
+ Use char because int might match the return type of a GCC
+ builtin and then its argument prototype would still apply. */
+#ifdef __cplusplus
+extern "C"
+#endif
+char pmem_memcpy ();
+int
+main ()
+{
+return pmem_memcpy ();
+ ;
+ return 0;
+}
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+ ac_cv_lib_pmem_pmem_memcpy=yes
+else
+ ac_cv_lib_pmem_pmem_memcpy=no
+fi
+rm -f core conftest.err conftest.$ac_objext \
+ conftest$ac_exeext conftest.$ac_ext
+LIBS=$ac_check_lib_save_LIBS
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_lib_pmem_pmem_memcpy" >&5
+$as_echo "$ac_cv_lib_pmem_pmem_memcpy" >&6; }
+if test "x$ac_cv_lib_pmem_pmem_memcpy" = xyes; then :
+ cat >>confdefs.h <<_ACEOF
+#define HAVE_LIBPMEM 1
+_ACEOF
+
+ LIBS="-lpmem $LIBS"
+
+else
+ as_fn_error $? "library 'libpmem' (version >= 1.5) is required for PMEM support" "$LINENO" 5
+fi
+
+fi
+
##
## Header files
@@ -14215,6 +14303,17 @@ fi
done
+fi
+
+if test "$with_libpmem" = yes ; then
+ ac_fn_c_check_header_mongrel "$LINENO" "libpmem.h" "ac_cv_header_libpmem_h" "$ac_includes_default"
+if test "x$ac_cv_header_libpmem_h" = xyes; then :
+
+else
+ as_fn_error $? "header file <libpmem.h> is required for PMEM support" "$LINENO" 5
+fi
+
+
fi
##
diff --git a/configure.ac b/configure.ac
index e77d4dcf2d2..2bea131375a 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1056,6 +1056,15 @@ if test "$with_lz4" = yes; then
done
fi
+#
+# libpmem
+#
+AC_MSG_CHECKING([whether to build with PMEM support])
+PGAC_ARG_BOOL(with, libpmem, no, [build with PMEM support],
+ [AC_DEFINE([USE_LIBPMEM], 1, [Define to 1 to build with PMEM support. (--with-libpmem)])])
+AC_MSG_RESULT([$with_libpmem])
+AC_SUBST(with_libpmem)
+
#
# Assignments
#
@@ -1385,6 +1394,10 @@ elif test "$with_uuid" = ossp ; then
fi
AC_SUBST(UUID_LIBS)
+if test "$with_libpmem" = yes; then
+ AC_CHECK_LIB(pmem, pmem_memcpy, [], [AC_MSG_ERROR([library 'libpmem' (version >= 1.5) is required for PMEM support])])
+fi
+
##
## Header files
@@ -1571,6 +1584,10 @@ if test "$PORTNAME" = "win32" ; then
AC_CHECK_HEADERS(crtdefs.h)
fi
+if test "$with_libpmem" = yes ; then
+ AC_CHECK_HEADER(libpmem.h, [], [AC_MSG_ERROR([header file <libpmem.h> is required for PMEM support])])
+fi
+
##
## Types, structures, compiler characteristics
##
diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in
index 7525c165974..96604aa130d 100644
--- a/src/include/pg_config.h.in
+++ b/src/include/pg_config.h.in
@@ -331,6 +331,9 @@
/* Define to 1 if you have the `pam' library (-lpam). */
#undef HAVE_LIBPAM
+/* Define to 1 if you have the `pmem' library (-lpmem). */
+#undef HAVE_LIBPMEM
+
/* Define if you have a function readline library */
#undef HAVE_LIBREADLINE
@@ -898,6 +901,9 @@
/* Define to 1 to build with LDAP support. (--with-ldap) */
#undef USE_LDAP
+/* Define to 1 to build with PMEM support. (--with-libpmem) */
+#undef USE_LIBPMEM
+
/* Define to 1 to build with XML support. (--with-libxml) */
#undef USE_LIBXML
--
2.17.1
>From f014b7923e9cee1f1f3cfd3ea23fc91ace3f1474 Mon Sep 17 00:00:00 2001
From: Takashi Menjo <takashi.menjou...@hco.ntt.co.jp>
Date: Fri, 5 Nov 2021 14:16:33 +0900
Subject: [PATCH 02/13] Support build with MSVC on Windows
---
src/tools/msvc/Solution.pm | 13 +++++++++++++
src/tools/msvc/config_default.pl | 3 ++-
2 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/src/tools/msvc/Solution.pm b/src/tools/msvc/Solution.pm
index 2c8cd521e94..d843391050b 100644
--- a/src/tools/msvc/Solution.pm
+++ b/src/tools/msvc/Solution.pm
@@ -304,6 +304,7 @@ sub GenerateFiles
HAVE_LIBLZ4 => undef,
HAVE_LIBM => undef,
HAVE_LIBPAM => undef,
+ HAVE_LIBPMEM => undef,
HAVE_LIBREADLINE => undef,
HAVE_LIBSELINUX => undef,
HAVE_LIBSSL => undef,
@@ -488,6 +489,7 @@ sub GenerateFiles
USE_BONJOUR => undef,
USE_BSD_AUTH => undef,
USE_ICU => $self->{options}->{icu} ? 1 : undef,
+ USE_LIBPMEM => undef,
USE_LIBXML => undef,
USE_LIBXSLT => undef,
USE_LZ4 => undef,
@@ -538,6 +540,11 @@ sub GenerateFiles
$define{HAVE_LZ4_H} = 1;
$define{USE_LZ4} = 1;
}
+ if ($self->{options}->{pmem})
+ {
+ $define{HAVE_LIBPMEM} = 1;
+ $define{USE_LIBPMEM} = 1;
+ }
if ($self->{options}->{openssl})
{
$define{USE_OPENSSL} = 1;
@@ -1085,6 +1092,11 @@ sub AddProject
$proj->AddIncludeDir($self->{options}->{uuid} . '\include');
$proj->AddLibrary($self->{options}->{uuid} . '\lib\uuid.lib');
}
+ if ($self->{options}->{pmem})
+ {
+ $proj->AddIncludeDir($self->{options}->{pmem} . '\include');
+ $proj->AddLibrary($self->{options}->{pmem} . '\lib\libpmem.lib');
+ }
return $proj;
}
@@ -1197,6 +1209,7 @@ sub GetFakeConfigure
$cfg .= ' --with-tcl' if ($self->{options}->{tcl});
$cfg .= ' --with-perl' if ($self->{options}->{perl});
$cfg .= ' --with-python' if ($self->{options}->{python});
+ $cfg .= ' --with-libpmem' if ($self->{options}->{pmem});
my $port = $self->{options}->{'--with-pgport'};
$cfg .= " --with-pgport=$port" if defined($port);
diff --git a/src/tools/msvc/config_default.pl b/src/tools/msvc/config_default.pl
index 460c0375d4b..774730c9a8f 100644
--- a/src/tools/msvc/config_default.pl
+++ b/src/tools/msvc/config_default.pl
@@ -25,7 +25,8 @@ our $config = {
xml => undef, # --with-libxml=<path>
xslt => undef, # --with-libxslt=<path>
iconv => undef, # (not in configure, path to iconv)
- zlib => undef # --with-zlib=<path>
+ zlib => undef, # --with-zlib=<path>
+ pmem => undef # --with-libpmem=<path>
};
1;
--
2.17.1
>From 7c2d6665a925dc5615f6ffd999374e10c3ea2199 Mon Sep 17 00:00:00 2001
From: Takashi Menjo <takashi.menjou...@hco.ntt.co.jp>
Date: Thu, 11 Mar 2021 17:55:53 +0900
Subject: [PATCH 03/13] Add wal_pmem_map to GUC
---
src/backend/access/transam/xlog.c | 51 ++++++++++++++++++++++++-------
src/backend/utils/misc/guc.c | 14 +++++++++
src/include/access/xlog.h | 1 +
3 files changed, 55 insertions(+), 11 deletions(-)
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 87cd05c9454..02f63c31387 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -115,6 +115,7 @@ int CommitSiblings = 5; /* # concurrent xacts needed to sleep */
int wal_retrieve_retry_interval = 5000;
int max_slot_wal_keep_size_mb = -1;
bool track_wal_io_timing = false;
+bool wal_pmem_map = false;
#ifdef WAL_DEBUG
bool XLOG_DEBUG = false;
@@ -5194,13 +5195,28 @@ XLOGShmemSize(void)
{
Size size;
+ /*
+ * If we use WAL segment files as WAL buffers, we don't use the given
+ * value of wal_buffers. Instead, we set it to the value based on the
+ * segment size and the page size. This should be done before calculating
+ * the size of xlblocks array.
+ */
+ if (wal_pmem_map)
+ {
+ int npages;
+ char buf[32];
+
+ npages = wal_segment_size / XLOG_BLCKSZ;
+ snprintf(buf, sizeof(buf), "%d", (int) npages);
+ SetConfigOption("wal_buffers", buf, PGC_POSTMASTER, PGC_S_OVERRIDE);
+ }
/*
* If the value of wal_buffers is -1, use the preferred auto-tune value.
* This isn't an amazingly clean place to do this, but we must wait till
* NBuffers has received its final value, and must do it before using the
* value of XLOGbuffers to do anything important.
*/
- if (XLOGbuffers == -1)
+ else if (XLOGbuffers == -1)
{
char buf[32];
@@ -5216,10 +5232,17 @@ XLOGShmemSize(void)
size = add_size(size, mul_size(sizeof(WALInsertLockPadded), NUM_XLOGINSERT_LOCKS + 1));
/* xlblocks array */
size = add_size(size, mul_size(sizeof(XLogRecPtr), XLOGbuffers));
- /* extra alignment padding for XLOG I/O buffers */
- size = add_size(size, XLOG_BLCKSZ);
- /* and the buffers themselves */
- size = add_size(size, mul_size(XLOG_BLCKSZ, XLOGbuffers));
+
+ /*
+ * If we use WAL segment files as WAL buffers, we don't need volatile ones.
+ */
+ if (!wal_pmem_map)
+ {
+ /* extra alignment padding for XLOG I/O buffers */
+ size = add_size(size, XLOG_BLCKSZ);
+ /* and the buffers themselves */
+ size = add_size(size, mul_size(XLOG_BLCKSZ, XLOGbuffers));
+ }
/*
* Note: we don't count ControlFileData, it comes out of the "slop factor"
@@ -5313,13 +5336,19 @@ XLOGShmemInit(void)
}
/*
- * Align the start of the page buffers to a full xlog block size boundary.
- * This simplifies some calculations in XLOG insertion. It is also
- * required for O_DIRECT.
+ * If we use WAL segment files as WAL buffers, we don't need volatile ones.
*/
- allocptr = (char *) TYPEALIGN(XLOG_BLCKSZ, allocptr);
- XLogCtl->pages = allocptr;
- memset(XLogCtl->pages, 0, (Size) XLOG_BLCKSZ * XLOGbuffers);
+ if (!wal_pmem_map)
+ {
+ /*
+ * Align the start of the page buffers to a full xlog block size boundary.
+ * This simplifies some calculations in XLOG insertion. It is also
+ * required for O_DIRECT.
+ */
+ allocptr = (char *) TYPEALIGN(XLOG_BLCKSZ, allocptr);
+ XLogCtl->pages = allocptr;
+ memset(XLogCtl->pages, 0, (Size) XLOG_BLCKSZ * XLOGbuffers);
+ }
/*
* Do basic initialization of XLogCtl shared data. (StartupXLOG will fill
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index f9504d3aec4..ee18a9cf338 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -1344,6 +1344,20 @@ static struct config_bool ConfigureNamesBool[] =
NULL, NULL, NULL
},
+#ifdef USE_LIBPMEM
+ {
+ {"wal_pmem_map", PGC_POSTMASTER, WAL_SETTINGS,
+ gettext_noop("Map WAL segment files on PMEM as WAL buffers."),
+ gettext_noop("If true, postgres will memory-map WAL segment files "
+ "on PMEM to use them as WAL buffers instead of the "
+ "traditional volatile ones."),
+ },
+ &wal_pmem_map,
+ false,
+ NULL, NULL, NULL
+ },
+#endif
+
{
{"log_checkpoints", PGC_SIGHUP, LOGGING_WHAT,
gettext_noop("Logs each checkpoint."),
diff --git a/src/include/access/xlog.h b/src/include/access/xlog.h
index 34f6c89f067..73900cbc9e7 100644
--- a/src/include/access/xlog.h
+++ b/src/include/access/xlog.h
@@ -88,6 +88,7 @@ extern char *PrimaryConnInfo;
extern char *PrimarySlotName;
extern bool wal_receiver_create_temp_slot;
extern bool track_wal_io_timing;
+extern bool wal_pmem_map;
/* indirectly set via GUC system */
extern TransactionId recoveryTargetXid;
--
2.17.1
>From a09110f5932cac18d7822d296d189de47698f70a Mon Sep 17 00:00:00 2001
From: Takashi Menjo <takashi.menjou...@hco.ntt.co.jp>
Date: Tue, 23 Mar 2021 07:32:05 +0900
Subject: [PATCH 04/13] Export InstallXLogFileSegment
---
src/backend/access/transam/xlog.c | 5 +----
src/include/access/xlog_internal.h | 4 ++++
2 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 02f63c31387..73a3477be04 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -923,9 +923,6 @@ static void AdvanceXLInsertBuffer(XLogRecPtr upto, TimeLineID tli,
bool opportunistic);
static bool XLogCheckpointNeeded(XLogSegNo new_segno);
static void XLogWrite(XLogwrtRqst WriteRqst, TimeLineID tli, bool flexible);
-static bool InstallXLogFileSegment(XLogSegNo *segno, char *tmppath,
- bool find_free, XLogSegNo max_segno,
- TimeLineID tli);
static int XLogFileRead(XLogSegNo segno, int emode, TimeLineID tli,
XLogSource source, bool notfoundOk);
static int XLogFileReadAnyTLI(XLogSegNo segno, int emode, XLogSource source);
@@ -3700,7 +3697,7 @@ XLogFileCopy(TimeLineID destTLI, XLogSegNo destsegno,
* max_segno limit was exceeded, the startup process has disabled this
* function for now, or an error occurred while renaming the file into place.
*/
-static bool
+bool
InstallXLogFileSegment(XLogSegNo *segno, char *tmppath,
bool find_free, XLogSegNo max_segno, TimeLineID tli)
{
diff --git a/src/include/access/xlog_internal.h b/src/include/access/xlog_internal.h
index c0da76cab49..328128b48d5 100644
--- a/src/include/access/xlog_internal.h
+++ b/src/include/access/xlog_internal.h
@@ -324,6 +324,10 @@ extern XLogRecPtr RequestXLogSwitch(bool mark_unimportant);
extern void GetOldestRestartPoint(XLogRecPtr *oldrecptr, TimeLineID *oldtli);
+extern bool InstallXLogFileSegment(XLogSegNo *segno, char *tmppath,
+ bool find_free, XLogSegNo max_segno,
+ TimeLineID tli);
+
/*
* Exported for the functions in timeline.c and xlogarchive.c. Only valid
* in the startup process.
--
2.17.1
>From 443e47112de2d8c735be0ce9bddb01e7e77de672 Mon Sep 17 00:00:00 2001
From: Takashi Menjo <takashi.menjou...@hco.ntt.co.jp>
Date: Tue, 23 Mar 2021 11:45:44 +0900
Subject: [PATCH 05/13] Map WAL segment files on PMEM as WAL buffers
Fixes introduced in patchset v2:
- Keep openLogSegNo even if wal_pmem_map=true
- Fix sync issue of PmemXLogCreate
- Fix unmapping issue of PmemXLogUnmap
- Remove unused XLogPageOffset
---
src/backend/access/transam/Makefile | 1 +
src/backend/access/transam/xlog.c | 153 +++++++++----
src/backend/access/transam/xlogpmem.c | 297 ++++++++++++++++++++++++++
src/include/access/xlogpmem.h | 59 +++++
4 files changed, 474 insertions(+), 36 deletions(-)
create mode 100644 src/backend/access/transam/xlogpmem.c
create mode 100644 src/include/access/xlogpmem.h
diff --git a/src/backend/access/transam/Makefile b/src/backend/access/transam/Makefile
index 595e02de722..3a29583bc03 100644
--- a/src/backend/access/transam/Makefile
+++ b/src/backend/access/transam/Makefile
@@ -31,6 +31,7 @@ OBJS = \
xlogarchive.o \
xlogfuncs.o \
xloginsert.o \
+ xlogpmem.o \
xlogreader.o \
xlogutils.o
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 73a3477be04..be56599f9fd 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -35,6 +35,7 @@
#include "access/xlog_internal.h"
#include "access/xlogarchive.h"
#include "access/xloginsert.h"
+#include "access/xlogpmem.h"
#include "access/xlogreader.h"
#include "access/xlogutils.h"
#include "catalog/catversion.h"
@@ -2024,7 +2025,14 @@ GetXLogBuffer(XLogRecPtr ptr, TimeLineID tli)
* offset within the page.
*/
cachedPage = ptr / XLOG_BLCKSZ;
- cachedPos = XLogCtl->pages + idx * (Size) XLOG_BLCKSZ;
+ if (wal_pmem_map)
+ {
+ openLogTLI = tli;
+ openLogSegNo = PmemXLogEnsurePrevMapped(endptr, tli);
+ cachedPos = PmemXLogGetBufferPages() + idx * (Size) XLOG_BLCKSZ;
+ }
+ else
+ cachedPos = XLogCtl->pages + idx * (Size) XLOG_BLCKSZ;
Assert(((XLogPageHeader) cachedPos)->xlp_magic == XLOG_PAGE_MAGIC);
Assert(((XLogPageHeader) cachedPos)->xlp_pageaddr == ptr - (ptr % XLOG_BLCKSZ));
@@ -2258,7 +2266,14 @@ AdvanceXLInsertBuffer(XLogRecPtr upto, TimeLineID tli, bool opportunistic)
Assert(XLogRecPtrToBufIdx(NewPageBeginPtr) == nextidx);
- NewPage = (XLogPageHeader) (XLogCtl->pages + nextidx * (Size) XLOG_BLCKSZ);
+ if (wal_pmem_map)
+ {
+ openLogTLI = tli;
+ openLogSegNo = PmemXLogEnsurePrevMapped(NewPageEndPtr, tli);
+ NewPage = (XLogPageHeader) (PmemXLogGetBufferPages() + nextidx * (Size) XLOG_BLCKSZ);
+ }
+ else
+ NewPage = (XLogPageHeader) (XLogCtl->pages + nextidx * (Size) XLOG_BLCKSZ);
/*
* Be sure to re-zero the buffer so that bytes beyond what we've
@@ -2477,6 +2492,8 @@ XLogWrite(XLogwrtRqst WriteRqst, TimeLineID tli, bool flexible)
int npages;
int startidx;
uint32 startoffset;
+ bool isfirstpage;
+ XLogRecPtr startpageptr;
/* We should always be inside a critical section here */
Assert(CritSectionCount > 0);
@@ -2499,6 +2516,10 @@ XLogWrite(XLogwrtRqst WriteRqst, TimeLineID tli, bool flexible)
startidx = 0;
startoffset = 0;
+ /* Those are used actually only if wal_pmem_map=true */
+ isfirstpage = true;
+ startpageptr = 0;
+
/*
* Within the loop, curridx is the cache block index of the page to
* consider writing. Begin at the buffer containing the next unwritten
@@ -2524,33 +2545,36 @@ XLogWrite(XLogwrtRqst WriteRqst, TimeLineID tli, bool flexible)
LogwrtResult.Write = EndPtr;
ispartialpage = WriteRqst.Write < LogwrtResult.Write;
- if (!XLByteInPrevSeg(LogwrtResult.Write, openLogSegNo,
- wal_segment_size))
+ if (!wal_pmem_map)
{
- /*
- * Switch to new logfile segment. We cannot have any pending
- * pages here (since we dump what we have at segment end).
- */
- Assert(npages == 0);
- if (openLogFile >= 0)
- XLogFileClose();
- XLByteToPrevSeg(LogwrtResult.Write, openLogSegNo,
- wal_segment_size);
- openLogTLI = tli;
+ if (!XLByteInPrevSeg(LogwrtResult.Write, openLogSegNo,
+ wal_segment_size))
+ {
+ /*
+ * Switch to new logfile segment. We cannot have any pending
+ * pages here (since we dump what we have at segment end).
+ */
+ Assert(npages == 0);
+ if (openLogFile >= 0)
+ XLogFileClose();
+ XLByteToPrevSeg(LogwrtResult.Write, openLogSegNo,
+ wal_segment_size);
+ openLogTLI = tli;
- /* create/use new log file */
- openLogFile = XLogFileInit(openLogSegNo, tli);
- ReserveExternalFD();
- }
+ /* create/use new log file */
+ openLogFile = XLogFileInit(openLogSegNo, tli);
+ ReserveExternalFD();
+ }
- /* Make sure we have the current logfile open */
- if (openLogFile < 0)
- {
- XLByteToPrevSeg(LogwrtResult.Write, openLogSegNo,
- wal_segment_size);
- openLogTLI = tli;
- openLogFile = XLogFileOpen(openLogSegNo, tli);
- ReserveExternalFD();
+ /* Make sure we have the current logfile open */
+ if (openLogFile < 0)
+ {
+ XLByteToPrevSeg(LogwrtResult.Write, openLogSegNo,
+ wal_segment_size);
+ openLogTLI = tli;
+ openLogFile = XLogFileOpen(openLogSegNo, tli);
+ ReserveExternalFD();
+ }
}
/* Add current page to the set of pending pages-to-dump */
@@ -2558,8 +2582,8 @@ XLogWrite(XLogwrtRqst WriteRqst, TimeLineID tli, bool flexible)
{
/* first of group */
startidx = curridx;
- startoffset = XLogSegmentOffset(LogwrtResult.Write - XLOG_BLCKSZ,
- wal_segment_size);
+ startpageptr = LogwrtResult.Write - XLOG_BLCKSZ;
+ startoffset = XLogSegmentOffset(startpageptr, wal_segment_size);
}
npages++;
@@ -2597,7 +2621,38 @@ XLogWrite(XLogwrtRqst WriteRqst, TimeLineID tli, bool flexible)
INSTR_TIME_SET_CURRENT(start);
pgstat_report_wait_start(WAIT_EVENT_WAL_WRITE);
- written = pg_pwrite(openLogFile, from, nleft, startoffset);
+
+ /*
+ * If we use a WAL segment file as WAL buffers, we cache-flush
+ * records on the buffers byte by byte, not page by page. To do
+ * so, here we fix the range being cache-flushed.
+ */
+ if (wal_pmem_map)
+ {
+ XLogRecPtr startbyteptr;
+ XLogRecPtr endbyteptr;
+
+ startbyteptr = (isfirstpage)
+ ? XLogCtl->LogwrtResult.Write
+ : startpageptr;
+
+ endbyteptr = (ispartialpage)
+ ? WriteRqst.Write
+ : LogwrtResult.Write;
+
+ /* Now we cache-flush records */
+ openLogTLI = tli;
+ openLogSegNo = PmemXLogEnsurePrevMapped(endbyteptr, tli);
+ PmemXLogFlush(startbyteptr, endbyteptr);
+
+ /* Mark the first page is consumed */
+ isfirstpage = false;
+
+ /* Tell all the "pages" have been written successfully */
+ written = nleft;
+ }
+ else
+ written = pg_pwrite(openLogFile, from, nleft, startoffset);
pgstat_report_wait_end();
/*
@@ -2655,7 +2710,10 @@ XLogWrite(XLogwrtRqst WriteRqst, TimeLineID tli, bool flexible)
*/
if (finishing_seg)
{
- issue_xlog_fsync(openLogFile, openLogSegNo, tli);
+ if (wal_pmem_map)
+ PmemXLogSync();
+ else
+ issue_xlog_fsync(openLogFile, openLogSegNo, tli);
/* signal that we need to wakeup walsenders later */
WalSndWakeupRequest();
@@ -2706,12 +2764,14 @@ XLogWrite(XLogwrtRqst WriteRqst, TimeLineID tli, bool flexible)
LogwrtResult.Flush < LogwrtResult.Write)
{
+ if (wal_pmem_map)
+ PmemXLogSync();
/*
* Could get here without iterating above loop, in which case we might
* have no open file or the wrong one. However, we do not need to
* fsync more than one file.
*/
- if (sync_method != SYNC_METHOD_OPEN &&
+ else if (sync_method != SYNC_METHOD_OPEN &&
sync_method != SYNC_METHOD_OPEN_DSYNC)
{
if (openLogFile >= 0 &&
@@ -8099,11 +8159,32 @@ StartupXLOG(void)
firstIdx = XLogRecPtrToBufIdx(EndOfLog);
- /* Copy the valid part of the last block, and zero the rest */
- page = &XLogCtl->pages[firstIdx * XLOG_BLCKSZ];
- len = EndOfLog % XLOG_BLCKSZ;
- memcpy(page, xlogreader->readBuf, len);
- memset(page + len, 0, XLOG_BLCKSZ - len);
+ if (wal_pmem_map)
+ {
+ /*
+ * Keep the valid part of the last block, and zero the rest.
+ * Note that "len" indicates the size of the valid part.
+ *
+ * TODO how about if (newTLI != replayTLI) ?
+ */
+ openLogTLI = newTLI;
+ openLogSegNo = PmemXLogEnsurePrevMapped(EndOfLog, newTLI);
+ page = PmemXLogGetBufferPages() + firstIdx * (Size) XLOG_BLCKSZ;
+ len = EndOfLog % XLOG_BLCKSZ;
+ memset(page + len, 0, XLOG_BLCKSZ - len);
+
+ /* Cache-flush and sync now */
+ PmemXLogFlush(EndOfLog, pageBeginPtr + XLOG_BLCKSZ);
+ PmemXLogSync();
+ }
+ else
+ {
+ /* Copy the valid part of the last block, and zero the rest */
+ page = &XLogCtl->pages[firstIdx * XLOG_BLCKSZ];
+ len = EndOfLog % XLOG_BLCKSZ;
+ memcpy(page, xlogreader->readBuf, len);
+ memset(page + len, 0, XLOG_BLCKSZ - len);
+ }
XLogCtl->xlblocks[firstIdx] = pageBeginPtr + XLOG_BLCKSZ;
XLogCtl->InitializedUpTo = pageBeginPtr + XLOG_BLCKSZ;
diff --git a/src/backend/access/transam/xlogpmem.c b/src/backend/access/transam/xlogpmem.c
new file mode 100644
index 00000000000..5b50ba80a7a
--- /dev/null
+++ b/src/backend/access/transam/xlogpmem.c
@@ -0,0 +1,297 @@
+#include "postgres.h"
+
+#ifdef USE_LIBPMEM
+
+#include <errno.h>
+#include <limits.h> /* INT_MAX */
+#include <stddef.h> /* size_t */
+#include <stdint.h> /* uintptr_t */
+#include <unistd.h> /* getpid, unlink */
+
+#include <libpmem.h>
+
+#include "c.h" /* bool, Size */
+#include "access/xlog.h"
+#include "access/xlog_internal.h" /* XLogFilePath, XLByteToSeg */
+#include "access/xlogpmem.h"
+#include "common/file_perm.h" /* pg_file_create_mode */
+#include "miscadmin.h" /* enableFsync */
+#include "pgstat.h"
+
+static char *mappedPages = NULL;
+static XLogSegNo mappedSegNo = 0;
+
+#define PG_DAX_HUGEPAGE_SIZE (((uintptr_t) 1) << 21)
+#define PG_DAX_HUGEPAGE_MASK (~(PG_DAX_HUGEPAGE_SIZE - 1))
+
+static XLogSegNo PmemXLogMap(XLogSegNo segno, TimeLineID tli);
+static void PmemXLogCreate(XLogSegNo segno, TimeLineID tli);
+static void PmemXLogUnmap(void);
+
+static void *PmemCreateMapFile(const char *path, size_t len);
+static void *PmemOpenMapFile(const char *path, size_t expected_len);
+static void *PmemTryOpenMapFile(const char *path, size_t expected_len);
+static void *PmemMapFile(const char *path, size_t expected_len, int flags,
+ bool try_open);
+static void PmemUnmapForError(void *addr, size_t len);
+
+/*
+ * Ensures the WAL segment containg {ptr-1} to be mapped.
+ *
+ * Returns mapped XLogSegNo.
+ */
+XLogSegNo
+PmemXLogEnsurePrevMapped(XLogRecPtr ptr, TimeLineID tli)
+{
+ XLogSegNo segno;
+
+ Assert(wal_pmem_map);
+
+ XLByteToPrevSeg(ptr, segno, wal_segment_size);
+
+ if (mappedPages != NULL)
+ {
+ /* Fast return: The segment we need is already mapped */
+ if (mappedSegNo == segno)
+ return mappedSegNo;
+
+ /* Unmap the current segment we don't need */
+ PmemXLogUnmap();
+ }
+
+ return PmemXLogMap(segno, tli);
+}
+
+/*
+ * Creates a new XLOG file segment, or open a pre-existing one, for WAL buffers.
+ *
+ * Returns mapped XLogSegNo.
+ *
+ * See also XLogFileInit in xlog.c.
+ */
+static XLogSegNo
+PmemXLogMap(XLogSegNo segno, TimeLineID tli)
+{
+ char path[MAXPGPATH];
+
+ Assert(mappedPages == NULL);
+
+ XLogFilePath(path, tli, segno, wal_segment_size);
+
+ /* PmemTryOpenMapFile will handle error except ENOENT */
+ mappedPages = PmemTryOpenMapFile(path, wal_segment_size);
+
+ /* Fast return if already exists */
+ if (mappedPages != NULL)
+ {
+ mappedSegNo = segno;
+ return mappedSegNo;
+ }
+
+ elog(DEBUG2, "creating and filling new WAL file");
+ PmemXLogCreate(segno, tli);
+
+ /* PmemCreateMapFile will handle error */
+ mappedPages = PmemOpenMapFile(path, wal_segment_size);
+ mappedSegNo = segno;
+
+ elog(DEBUG2, "done creating and filling new WAL file");
+ return mappedSegNo;
+}
+
+/*
+ * Creates a new XLOG file segment.
+ *
+ * See also XLogFileInit in xlog.c.
+ */
+static void
+PmemXLogCreate(XLogSegNo segno, TimeLineID tli)
+{
+ char *addr;
+ char tmppath[MAXPGPATH];
+ XLogSegNo inst_segno;
+ XLogSegNo max_segno;
+
+ snprintf(tmppath, MAXPGPATH, XLOGDIR "/xlogtemp.%d", (int) getpid());
+ unlink(tmppath);
+
+ /* PmemCreateMapFile will handle error */
+ addr = PmemCreateMapFile(tmppath, wal_segment_size);
+
+ /*
+ * Initialize whole the buffers.
+ *
+ * Note that we don't put any single byte if not wal_init_zero. It's okay
+ * because we already have a new segment file truncated to the proper size.
+ */
+ pgstat_report_wait_start(WAIT_EVENT_WAL_INIT_WRITE);
+ if (wal_init_zero)
+ pmem_memset_nodrain(addr, 0, wal_segment_size);
+ pgstat_report_wait_end();
+
+ pgstat_report_wait_start(WAIT_EVENT_WAL_INIT_SYNC);
+ if (enableFsync)
+ pmem_drain();
+ pgstat_report_wait_end();
+
+ if (pmem_unmap(addr, wal_segment_size) < 0)
+ elog(ERROR, "could not pmem_unmap temporal WAL buffers: %m");
+
+ inst_segno = segno;
+ max_segno = segno + CheckPointSegments;
+ if (!InstallXLogFileSegment(&inst_segno, tmppath, true, max_segno, tli))
+ unlink(tmppath);
+}
+
+/*
+ * Unmaps the current WAL segment file if mapped.
+ */
+static void
+PmemXLogUnmap(void)
+{
+ /* Fast return if not mapped */
+ if (mappedPages == NULL)
+ return;
+
+ if (pmem_unmap(mappedPages, wal_segment_size) < 0)
+ elog(ERROR, "could not pmem_unmap WAL buffers: %m");
+
+ mappedPages = NULL;
+}
+
+/*
+ * Gets the head address of the WAL buffers.
+ */
+char *
+PmemXLogGetBufferPages(void)
+{
+ Assert(wal_pmem_map);
+ Assert(mappedPages != NULL);
+
+ return mappedPages;
+}
+
+/*
+ * Flushes records in the given range [start, end) within a single segment.
+ */
+void
+PmemXLogFlush(XLogRecPtr start, XLogRecPtr end)
+{
+ Size off;
+
+ Assert(wal_pmem_map);
+ Assert(start < end);
+ Assert(mappedPages != NULL);
+ Assert(XLByteInSeg(start, mappedSegNo, wal_segment_size));
+ Assert(XLByteInPrevSeg(end, mappedSegNo, wal_segment_size));
+
+ off = XLogSegmentOffset(start, wal_segment_size);
+ pmem_flush(mappedPages + off, end - start);
+}
+
+/*
+ * Wait for cache-flush to finish.
+ */
+void
+PmemXLogSync(void)
+{
+ Assert(wal_pmem_map);
+
+ /* Fast return */
+ if (!enableFsync)
+ return;
+
+ pmem_drain();
+}
+
+/*
+ * Wrappers for pmem_map_file.
+ */
+static void *
+PmemCreateMapFile(const char *path, size_t len)
+{
+ return PmemMapFile(path, len, PMEM_FILE_CREATE | PMEM_FILE_EXCL, false);
+}
+
+static void *
+PmemOpenMapFile(const char *path, size_t expected_len)
+{
+ return PmemMapFile(path, expected_len, 0, false);
+}
+
+static void *
+PmemTryOpenMapFile(const char *path, size_t expected_len)
+{
+ return PmemMapFile(path, expected_len, 0, true);
+}
+
+static void *
+PmemMapFile(const char *path, size_t expected_len, int flags, bool try_open)
+{
+ size_t param_len;
+ int mode;
+ size_t mapped_len;
+ int is_pmem;
+ void *addr;
+
+ Assert(expected_len > 0);
+ Assert(expected_len <= INT_MAX);
+
+ param_len = (flags & PMEM_FILE_CREATE) ? expected_len : 0;
+ mode = (flags & PMEM_FILE_CREATE) ? pg_file_create_mode : 0;
+
+ mapped_len = 0;
+ is_pmem = 0;
+ addr = pmem_map_file(path, param_len, flags, mode, &mapped_len, &is_pmem);
+
+ if (addr == NULL)
+ {
+ if (try_open && errno == ENOENT)
+ return NULL;
+
+ ereport(ERROR,
+ (errcode_for_file_access(),
+ errmsg("could not pmem_map_file \"%s\": %m", path)));
+ }
+
+ if (mapped_len > INT_MAX)
+ {
+ PmemUnmapForError(addr, mapped_len);
+ elog(ERROR,
+ "unexpected file size: path \"%s\" actual (greater than %d) expected %d",
+ path, INT_MAX, (int) expected_len);
+ }
+
+ if (mapped_len != expected_len)
+ {
+ PmemUnmapForError(addr, mapped_len);
+ elog(ERROR,
+ "unexpected file size: path \"%s\" actual %d expected %d",
+ path, (int) mapped_len, (int) expected_len);
+ }
+
+ if (!is_pmem)
+ {
+ PmemUnmapForError(addr, mapped_len);
+ elog(ERROR, "file not on PMEM: path \"%s\"", path);
+ }
+
+ if ((uintptr_t) addr & ~PG_DAX_HUGEPAGE_MASK)
+ elog(WARNING,
+ "file not mapped on DAX hugepage boundary: path \"%s\" addr %p",
+ path, addr);
+
+ return addr;
+}
+
+static void
+PmemUnmapForError(void *addr, size_t len)
+{
+ int saved_errno;
+
+ saved_errno = errno;
+ (void) pmem_unmap(addr, len);
+ errno = saved_errno;
+}
+
+#endif /* USE_LIBPMEM */
diff --git a/src/include/access/xlogpmem.h b/src/include/access/xlogpmem.h
new file mode 100644
index 00000000000..3978640b82f
--- /dev/null
+++ b/src/include/access/xlogpmem.h
@@ -0,0 +1,59 @@
+/*
+ * xlogpmem.h
+ *
+ * Definitions for PMEM-mapped WAL buffers.
+ *
+ * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * src/include/access/xlogpmem.h
+ */
+#ifndef XLOGPMEM_H
+#define XLOGPMEM_H
+
+#include "postgres.h"
+
+#include "c.h" /* Size */
+#include "access/xlogdefs.h" /* XLogRecPtr, XLogSegNo */
+
+#ifdef USE_LIBPMEM
+
+/* Prototypes */
+extern XLogSegNo PmemXLogEnsurePrevMapped(XLogRecPtr ptr, TimeLineID tli);
+extern char *PmemXLogGetBufferPages(void);
+extern void PmemXLogFlush(XLogRecPtr start, XLogRecPtr end);
+extern void PmemXLogSync(void);
+
+#else /* USE_LIBPMEM */
+
+#include <stdlib.h> /* abort */
+
+static inline XLogSegNo
+PmemXLogEnsurePrevMapped(XLogRecPtr ptr, tli)
+{
+ abort();
+ return 0;
+}
+
+static inline char *
+PmemXLogGetBufferPages(void)
+{
+ abort();
+ return NULL;
+}
+
+static inline void
+PmemXLogFlush(XLogRecPtr start, XLogRecPtr end)
+{
+ abort();
+}
+
+static inline void
+PmemXLogSync(void)
+{
+ abort();
+}
+
+#endif /* USE_LIBPMEM */
+
+#endif /* XLOGPMEM_H */
--
2.17.1
>From 90ea943904793c5212cd1fed450e4f3b1f97f8a7 Mon Sep 17 00:00:00 2001
From: Justin Pryzby <pryz...@telsasoft.com>
Date: Wed, 5 Jan 2022 21:28:51 -0600
Subject: [PATCH 06/13] compile-fix-without-pmem
---
src/include/access/xlogpmem.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/src/include/access/xlogpmem.h b/src/include/access/xlogpmem.h
index 3978640b82f..cd83bffc883 100644
--- a/src/include/access/xlogpmem.h
+++ b/src/include/access/xlogpmem.h
@@ -29,7 +29,7 @@ extern void PmemXLogSync(void);
#include <stdlib.h> /* abort */
static inline XLogSegNo
-PmemXLogEnsurePrevMapped(XLogRecPtr ptr, tli)
+PmemXLogEnsurePrevMapped(XLogRecPtr ptr, TimeLineID tli)
{
abort();
return 0;
--
2.17.1
>From 9b8091780f0156b35297beaecc5868a2df835e80 Mon Sep 17 00:00:00 2001
From: Takashi Menjo <takashi.menjou...@hco.ntt.co.jp>
Date: Fri, 5 Nov 2021 14:16:25 +0900
Subject: [PATCH 07/13] Compatible to Windows
---
src/backend/access/transam/xlogpmem.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)
diff --git a/src/backend/access/transam/xlogpmem.c b/src/backend/access/transam/xlogpmem.c
index 5b50ba80a7a..8bd990f1cd0 100644
--- a/src/backend/access/transam/xlogpmem.c
+++ b/src/backend/access/transam/xlogpmem.c
@@ -8,7 +8,24 @@
#include <stdint.h> /* uintptr_t */
#include <unistd.h> /* getpid, unlink */
+/*
+ * On Windows, we will have two ported but conflicting mode_t:
+ *
+ * mode_t in libpmem:
+ * libpmem.h -> pmemcompat.h -> typedef int mode_t
+ * mode_t in PostgreSQL:
+ * c.h -> port.h -> win32_port.h -> typedef unsigned short mode_t
+ *
+ * We want to use PostgreSQL's one, so conseal libpmem's one.
+ */
+#if defined(WIN32) && !defined(__CYGWIN__)
+#define mode_t unused_libpmem_mode_t
+#include <libpmem.h>
+#undef mode_t
+/* On other platforms, simply include libpmem.h */
+#else
#include <libpmem.h>
+#endif
#include "c.h" /* bool, Size */
#include "access/xlog.h"
@@ -242,7 +259,11 @@ PmemMapFile(const char *path, size_t expected_len, int flags, bool try_open)
mapped_len = 0;
is_pmem = 0;
+#if defined(WIN32) && !defined(__CYGWIN__)
+ addr = pmem_map_fileU(path, param_len, flags, mode, &mapped_len, &is_pmem);
+#else
addr = pmem_map_file(path, param_len, flags, mode, &mapped_len, &is_pmem);
+#endif
if (addr == NULL)
{
--
2.17.1
>From 35c77c59d2e4aec95d6c1489b052d4456855f72f Mon Sep 17 00:00:00 2001
From: Takashi Menjo <takashi.menjou...@hco.ntt.co.jp>
Date: Wed, 19 May 2021 11:57:49 +0900
Subject: [PATCH 08/13] WAL statistics in cases of wal_pmem_map=true
---
src/backend/access/transam/xlogpmem.c | 47 +++++++++++++++++++++++++++
1 file changed, 47 insertions(+)
diff --git a/src/backend/access/transam/xlogpmem.c b/src/backend/access/transam/xlogpmem.c
index 8bd990f1cd0..d91fb2175b7 100644
--- a/src/backend/access/transam/xlogpmem.c
+++ b/src/backend/access/transam/xlogpmem.c
@@ -195,6 +195,7 @@ void
PmemXLogFlush(XLogRecPtr start, XLogRecPtr end)
{
Size off;
+ instr_time start_time;
Assert(wal_pmem_map);
Assert(start < end);
@@ -203,22 +204,68 @@ PmemXLogFlush(XLogRecPtr start, XLogRecPtr end)
Assert(XLByteInPrevSeg(end, mappedSegNo, wal_segment_size));
off = XLogSegmentOffset(start, wal_segment_size);
+
+ /* Measure I/O timing to write WAL data */
+ if (track_wal_io_timing)
+ INSTR_TIME_SET_CURRENT(start_time);
+
+ pgstat_report_wait_start(WAIT_EVENT_WAL_WRITE);
pmem_flush(mappedPages + off, end - start);
+ pgstat_report_wait_end();
+
+ /*
+ * Increment the I/O timing and the number of times WAL data
+ * were written out to disk.
+ */
+ if (track_wal_io_timing)
+ {
+ instr_time duration;
+
+ INSTR_TIME_SET_CURRENT(duration);
+ INSTR_TIME_SUBTRACT(duration, start_time);
+ WalStats.m_wal_write_time += INSTR_TIME_GET_MICROSEC(duration);
+ }
+
+ WalStats.m_wal_write++;
}
/*
* Wait for cache-flush to finish.
+ *
+ * See also issue_xlog_fsync in xlog.c.
*/
void
PmemXLogSync(void)
{
+ instr_time start;
+
Assert(wal_pmem_map);
/* Fast return */
if (!enableFsync)
return;
+ /* Measure I/O timing to sync the WAL file */
+ if (track_wal_io_timing)
+ INSTR_TIME_SET_CURRENT(start);
+
+ pgstat_report_wait_start(WAIT_EVENT_WAL_SYNC);
pmem_drain();
+ pgstat_report_wait_end();
+
+ /*
+ * Increment the I/O timing and the number of times WAL files were synced.
+ */
+ if (track_wal_io_timing)
+ {
+ instr_time duration;
+
+ INSTR_TIME_SET_CURRENT(duration);
+ INSTR_TIME_SUBTRACT(duration, start);
+ WalStats.m_wal_sync_time += INSTR_TIME_GET_MICROSEC(duration);
+ }
+
+ WalStats.m_wal_sync++;
}
/*
--
2.17.1
>From 557ae7c84ea24bc6c7c42104144c422b0154d166 Mon Sep 17 00:00:00 2001
From: Takashi Menjo <takashi.menjou...@hco.ntt.co.jp>
Date: Wed, 13 Oct 2021 11:10:17 +0900
Subject: [PATCH 09/13] Let wal_pmem_map be constant unless --with-libpmem
---
src/backend/access/transam/xlog.c | 3 +++
src/include/access/xlog.h | 5 +++++
2 files changed, 8 insertions(+)
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index be56599f9fd..62f08cb50bb 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -116,7 +116,10 @@ int CommitSiblings = 5; /* # concurrent xacts needed to sleep */
int wal_retrieve_retry_interval = 5000;
int max_slot_wal_keep_size_mb = -1;
bool track_wal_io_timing = false;
+
+#ifdef USE_LIBPMEM
bool wal_pmem_map = false;
+#endif
#ifdef WAL_DEBUG
bool XLOG_DEBUG = false;
diff --git a/src/include/access/xlog.h b/src/include/access/xlog.h
index 73900cbc9e7..ab3eb3887b9 100644
--- a/src/include/access/xlog.h
+++ b/src/include/access/xlog.h
@@ -88,7 +88,12 @@ extern char *PrimaryConnInfo;
extern char *PrimarySlotName;
extern bool wal_receiver_create_temp_slot;
extern bool track_wal_io_timing;
+
+#ifdef USE_LIBPMEM
extern bool wal_pmem_map;
+#else
+#define wal_pmem_map false
+#endif
/* indirectly set via GUC system */
extern TransactionId recoveryTargetXid;
--
2.17.1
>From 133e1281d4b308df6f63edebae94cf1856598af4 Mon Sep 17 00:00:00 2001
From: Takashi Menjo <takashi.menjou...@hco.ntt.co.jp>
Date: Thu, 28 Oct 2021 13:35:28 +0900
Subject: [PATCH 10/13] Ensure WAL mappings before assertion
---
src/backend/access/transam/xlog.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index 62f08cb50bb..f0d7a317d23 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -1945,6 +1945,23 @@ GetXLogBuffer(XLogRecPtr ptr, TimeLineID tli)
*/
if (ptr / XLOG_BLCKSZ == cachedPage)
{
+ /*
+ * Ensure WAL mappings before assersion.
+ *
+ * cachedPos should be recaluculated because it has been probably
+ * invalidated due to WAL remapping. This should be done even if
+ * openLogSegNo seems not to change because the address of the
+ * mapping could have changed (ABA problem).
+ */
+ if (wal_pmem_map)
+ {
+ endptr = ptr - ptr % XLOG_BLCKSZ + XLOG_BLCKSZ;
+ openLogSegNo = PmemXLogEnsurePrevMapped(endptr, tli);
+ cachedPos = PmemXLogGetBufferPages() +
+ (Size) XLogSegmentOffset(endptr - XLOG_BLCKSZ,
+ wal_segment_size);
+ }
+
Assert(((XLogPageHeader) cachedPos)->xlp_magic == XLOG_PAGE_MAGIC);
Assert(((XLogPageHeader) cachedPos)->xlp_pageaddr == ptr - (ptr % XLOG_BLCKSZ));
return cachedPos + ptr % XLOG_BLCKSZ;
--
2.17.1
>From f3a91d9198d6498c156b8078b77f0e4c401e224f Mon Sep 17 00:00:00 2001
From: Takashi Menjo <takashi.menjou...@hco.ntt.co.jp>
Date: Thu, 30 Sep 2021 12:51:56 +0900
Subject: [PATCH 11/13] Update document
---
doc/src/sgml/config.sgml | 27 +++++++++++++++++++++++++++
1 file changed, 27 insertions(+)
diff --git a/doc/src/sgml/config.sgml b/doc/src/sgml/config.sgml
index 10aa18b7636..5e55564f42a 100644
--- a/doc/src/sgml/config.sgml
+++ b/doc/src/sgml/config.sgml
@@ -3239,6 +3239,33 @@ include_dir 'conf.d'
</listitem>
</varlistentry>
+ <varlistentry id="guc-wal-pmem-map" xreflabel="wal_pmem_map">
+ <term><varname>wal_pmem_map</varname> (<type>boolean</type>)
+ <indexterm>
+ <primary><varname>wal_pmem_map</varname> configuration parameter</primary>
+ </indexterm>
+ </term>
+ <listitem>
+ <para>
+ If set to <literal>on</literal>, this parameter causes WAL files to be
+ memory-mapped and used as WAL buffer pages. The WAL files in pg_wal
+ directory (or the directory given by <command>initdb -X</command>
+ option) should be on <firstterm>persistent memory</firstterm> (PMEM) and
+ the filesystem for those files should support the <firstterm>Direct
+ Access</firstterm> (DAX) feature. <varname>wal_sync_method</varname>
+ for the primary server is ignored and WAL updates are forced out to
+ PMEM in a more optimal way which avoids calling into the kernel.
+ <varname>min_wal_size</varname> should be multiple of the size of a
+ WAL file, and <varname>wal_buffers</varname> is ignored and set to
+ the equivalent of <varname>min_wal_size</varname>.
+ </para>
+ <para>
+ This parameter can only be set at server start. The default is
+ <literal>off</literal>.
+ </para>
+ </listitem>
+ </varlistentry>
+
<varlistentry id="guc-wal-writer-delay" xreflabel="wal_writer_delay">
<term><varname>wal_writer_delay</varname> (<type>integer</type>)
<indexterm>
--
2.17.1
>From b5d695e660b2dad66c96c5944d343ba0e825c7c3 Mon Sep 17 00:00:00 2001
From: Takashi Menjo <takashi.menjou...@hco.ntt.co.jp>
Date: Tue, 1 Jun 2021 19:29:22 +0900
Subject: [PATCH 12/13] Preallocate and initialize more WAL if
wal_pmem_map=true
---
src/backend/access/transam/xlog.c | 30 ++++++++++++++++++++++++------
src/backend/utils/misc/guc.c | 2 +-
2 files changed, 25 insertions(+), 7 deletions(-)
diff --git a/src/backend/access/transam/xlog.c b/src/backend/access/transam/xlog.c
index f0d7a317d23..1196ae21e80 100644
--- a/src/backend/access/transam/xlog.c
+++ b/src/backend/access/transam/xlog.c
@@ -2049,7 +2049,9 @@ GetXLogBuffer(XLogRecPtr ptr, TimeLineID tli)
{
openLogTLI = tli;
openLogSegNo = PmemXLogEnsurePrevMapped(endptr, tli);
- cachedPos = PmemXLogGetBufferPages() + idx * (Size) XLOG_BLCKSZ;
+ cachedPos = PmemXLogGetBufferPages() +
+ (Size) XLogSegmentOffset(endptr - XLOG_BLCKSZ,
+ wal_segment_size);
}
else
cachedPos = XLogCtl->pages + idx * (Size) XLOG_BLCKSZ;
@@ -2290,7 +2292,9 @@ AdvanceXLInsertBuffer(XLogRecPtr upto, TimeLineID tli, bool opportunistic)
{
openLogTLI = tli;
openLogSegNo = PmemXLogEnsurePrevMapped(NewPageEndPtr, tli);
- NewPage = (XLogPageHeader) (PmemXLogGetBufferPages() + nextidx * (Size) XLOG_BLCKSZ);
+ NewPage = (XLogPageHeader)
+ (PmemXLogGetBufferPages() +
+ (Size) XLogSegmentOffset(NewPageBeginPtr, wal_segment_size));
}
else
NewPage = (XLogPageHeader) (XLogCtl->pages + nextidx * (Size) XLOG_BLCKSZ);
@@ -5275,15 +5279,25 @@ XLOGShmemSize(void)
/*
* If we use WAL segment files as WAL buffers, we don't use the given
* value of wal_buffers. Instead, we set it to the value based on the
- * segment size and the page size. This should be done before calculating
+ * min_wal_size and the page size. This should be done before calculating
* the size of xlblocks array.
+ *
+ * TODO Do not allow changing min_wal_size by SIGHUP if wal_pmem_map=true.
+ *
+ * TODO Move validations to check_hook functions.
*/
if (wal_pmem_map)
{
int npages;
char buf[32];
- npages = wal_segment_size / XLOG_BLCKSZ;
+ if (min_wal_size_mb % (wal_segment_size / (1024 * 1024)) != 0)
+ elog(PANIC, "min_wal_size should be multiple of wal_segment_size when wal_pmem_map=true");
+
+ if (min_wal_size_mb / (XLOG_BLCKSZ / 1024) > INT_MAX / 1024)
+ elog(PANIC, "too many wal buffer pages");
+
+ npages = min_wal_size_mb / (XLOG_BLCKSZ / 1024) * 1024;
snprintf(buf, sizeof(buf), "%d", (int) npages);
SetConfigOption("wal_buffers", buf, PGC_POSTMASTER, PGC_S_OVERRIDE);
}
@@ -8189,7 +8203,8 @@ StartupXLOG(void)
*/
openLogTLI = newTLI;
openLogSegNo = PmemXLogEnsurePrevMapped(EndOfLog, newTLI);
- page = PmemXLogGetBufferPages() + firstIdx * (Size) XLOG_BLCKSZ;
+ page = PmemXLogGetBufferPages() +
+ (Size) XLogSegmentOffset(pageBeginPtr, wal_segment_size);
len = EndOfLog % XLOG_BLCKSZ;
memset(page + len, 0, XLOG_BLCKSZ - len);
@@ -8229,7 +8244,10 @@ StartupXLOG(void)
/*
* Preallocate additional log files, if wanted.
*/
- PreallocXlogFiles(EndOfLog, newTLI);
+ if (wal_pmem_map)
+ AdvanceXLInsertBuffer(InvalidXLogRecPtr, newTLI, true);
+ else
+ PreallocXlogFiles(EndOfLog, newTLI);
/*
* Okay, we're officially UP.
diff --git a/src/backend/utils/misc/guc.c b/src/backend/utils/misc/guc.c
index ee18a9cf338..6f667d5c43f 100644
--- a/src/backend/utils/misc/guc.c
+++ b/src/backend/utils/misc/guc.c
@@ -2866,7 +2866,7 @@ static struct config_int ConfigureNamesInt[] =
GUC_UNIT_XBLOCKS
},
&XLOGbuffers,
- -1, -1, (INT_MAX / XLOG_BLCKSZ),
+ -1, -1, INT_MAX,
check_wal_buffers, NULL, NULL
},
--
2.17.1
