On Fri, Mar 10, 2023 at 9:54 AM Michael Paquier <[email protected]> wrote:
>
> Hmm. I think this patch ought to have a result simpler than what's
> proposed here.
>
> First, do we really have to begin marking the functions as non-STRICT
> to abide with the treatment of NULL as a special value? The part that
> I've found personally the most annoying with these functions is that
> an incorrect bound leads to a random failure, particularly when such
> queries are used for monitoring. I would simplify the whole with two
> simple rules, as of:
> - Keeping all the functions strict.
> - When end_lsn is a LSN in the future of the current LSN inserted or
> replayed, adjust its value to be the exactly GetXLogReplayRecPtr() or
> GetFlushRecPtr(). This way, monitoring tools can use a value ahead,
> at will.
> - Failing if start_lsn > end_lsn.
> - Failing if start_lsn refers to a position older than what exists is
> still fine by me.
Done this way in the attached v5 patch.
> I would also choose to remove
> pg_get_wal_records_info_till_end_of_wal() from the SQL interface in
> 1.1 to limit the confusion arount it, but keep a few lines of code so
> as we are still able to use it when pg_walinspect 1.0 is the version
> enabled with CREATE EXTENSION.
>
> In short, pg_get_wal_records_info_till_end_of_wal() should be able to
> use exactly the same code as pg_get_wal_records_info(), still you need
> to keep *two* functions for their prosrc with PG_FUNCTION_ARGS as
> arguments so as 1.0 would work when dropped in place. The result, it
> seems to me, mostly comes to simplify ValidateInputLSNs() and remove
> its till_end_of_wal argument.
This has already been taken care of in the previous patches, e.g. v3
and v4 and so in the latest v5 patch.
> +-- Removed function
> +SELECT
> pg_get_functiondef('pg_get_wal_records_info_till_end_of_wal'::regproc);
> +ERROR: function "pg_get_wal_records_info_till_end_of_wal" does not exist
> +LINE 1: SELECT pg_get_functiondef('pg_get_wal_records_info_till_end_...
>
> It seems to me that you should just replace all that and anything
> depending on pg_get_functiondef() with a \dx+ pg_walinspect, that
> would list all the objects part of the extension for the specific
> version you want to test. Not sure that there is a need to list the
> full function definitions, either. That just bloats the tests.
Agreed and used \dx+. One can anyways look at the function definitions
and compare for knowing what's changed.
> I think, however, that it is critical to test in oldextversions.out
> the *executions* of the functions, so as we make sure that they don't
> crash. The patch is missing that.
You mean, we need to test the till_end_of_wal functions that were
removed in the latest version 1.1 but they must work if the extension
is installed with 1.0? If yes, I now added them.
> +-- Invalid input LSNs
> +SELECT * FROM pg_get_wal_record_info('0/0'); -- ERROR
> +ERROR: invalid input LSN
Removed InvalidRecPtr checks for input/start LSN because anyways the
functions will fail with ERROR: could not read WAL at LSN 0/0.
Any comments on the attached v5 patch?
--
Bharath Rupireddy
PostgreSQL Contributors Team
RDS Open Source Databases
Amazon Web Services: https://aws.amazon.com
From 63360cfa8c2a3141a1360a966bc7e210eb57810b Mon Sep 17 00:00:00 2001
From: Bharath Rupireddy <[email protected]>
Date: Fri, 10 Mar 2023 10:54:20 +0000
Subject: [PATCH v5] Rework pg_walinspect functions
---
contrib/pg_walinspect/Makefile | 2 +-
.../pg_walinspect/expected/oldextversions.out | 55 +++++
.../pg_walinspect/expected/pg_walinspect.out | 60 ++++-
contrib/pg_walinspect/meson.build | 1 +
.../pg_walinspect/pg_walinspect--1.0--1.1.sql | 4 +
contrib/pg_walinspect/pg_walinspect.c | 213 ++++++++----------
contrib/pg_walinspect/sql/oldextversions.sql | 29 +++
contrib/pg_walinspect/sql/pg_walinspect.sql | 74 +++---
doc/src/sgml/pgwalinspect.sgml | 88 ++++----
9 files changed, 307 insertions(+), 219 deletions(-)
create mode 100644 contrib/pg_walinspect/expected/oldextversions.out
create mode 100644 contrib/pg_walinspect/sql/oldextversions.sql
diff --git a/contrib/pg_walinspect/Makefile b/contrib/pg_walinspect/Makefile
index 7033878a79..22090f7716 100644
--- a/contrib/pg_walinspect/Makefile
+++ b/contrib/pg_walinspect/Makefile
@@ -9,7 +9,7 @@ PGFILEDESC = "pg_walinspect - functions to inspect contents of PostgreSQL Write-
EXTENSION = pg_walinspect
DATA = pg_walinspect--1.0.sql pg_walinspect--1.0--1.1.sql
-REGRESS = pg_walinspect
+REGRESS = pg_walinspect oldextversions
REGRESS_OPTS = --temp-config $(top_srcdir)/contrib/pg_walinspect/walinspect.conf
diff --git a/contrib/pg_walinspect/expected/oldextversions.out b/contrib/pg_walinspect/expected/oldextversions.out
new file mode 100644
index 0000000000..4ad85392f0
--- /dev/null
+++ b/contrib/pg_walinspect/expected/oldextversions.out
@@ -0,0 +1,55 @@
+-- test old extension version entry points
+DROP EXTENSION pg_walinspect;
+CREATE EXTENSION pg_walinspect WITH VERSION '1.0';
+-- List what version 1.0 contains
+\dx+ pg_walinspect
+ Objects in extension "pg_walinspect"
+ Object description
+-----------------------------------------------------------
+ function pg_get_wal_record_info(pg_lsn)
+ function pg_get_wal_records_info(pg_lsn,pg_lsn)
+ function pg_get_wal_records_info_till_end_of_wal(pg_lsn)
+ function pg_get_wal_stats(pg_lsn,pg_lsn,boolean)
+ function pg_get_wal_stats_till_end_of_wal(pg_lsn,boolean)
+(5 rows)
+
+-- ===================================================================
+-- Tests to check if the removed functions work when older version of
+-- extension is explicitly installed.
+-- ===================================================================
+-- Make sure checkpoints don't interfere with the test.
+SELECT 'init' FROM pg_create_physical_replication_slot('regress_pg_walinspect_slot', true, false);
+ ?column?
+----------
+ init
+(1 row)
+
+CREATE TABLE sample_tbl(col1 int, col2 int);
+SELECT pg_current_wal_lsn() AS wal_lsn1 \gset
+INSERT INTO sample_tbl SELECT * FROM generate_series(1, 2);
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_records_info_till_end_of_wal(:'wal_lsn1');
+ ok
+----
+ t
+(1 row)
+
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_stats_till_end_of_wal(:'wal_lsn1');
+ ok
+----
+ t
+(1 row)
+
+-- Move to new version 1.1
+ALTER EXTENSION pg_walinspect UPDATE TO '1.1';
+-- List what version 1.1 contains
+\dx+ pg_walinspect
+ Objects in extension "pg_walinspect"
+ Object description
+--------------------------------------------------
+ function pg_get_wal_block_info(pg_lsn,pg_lsn)
+ function pg_get_wal_record_info(pg_lsn)
+ function pg_get_wal_records_info(pg_lsn,pg_lsn)
+ function pg_get_wal_stats(pg_lsn,pg_lsn,boolean)
+(4 rows)
+
+DROP EXTENSION pg_walinspect;
diff --git a/contrib/pg_walinspect/expected/pg_walinspect.out b/contrib/pg_walinspect/expected/pg_walinspect.out
index e0eb7ca08f..d3ddc2409c 100644
--- a/contrib/pg_walinspect/expected/pg_walinspect.out
+++ b/contrib/pg_walinspect/expected/pg_walinspect.out
@@ -1,11 +1,12 @@
CREATE EXTENSION pg_walinspect;
--- Make sure checkpoints don't interfere with the test.
+-- Make sure checkpoints don't interfere with the test
SELECT 'init' FROM pg_create_physical_replication_slot('regress_pg_walinspect_slot', true, false);
?column?
----------
init
(1 row)
+-- Generate WAL and captures LSNs as needed
CREATE TABLE sample_tbl(col1 int, col2 int);
SELECT pg_current_wal_lsn() AS wal_lsn1 \gset
INSERT INTO sample_tbl SELECT * FROM generate_series(1, 2);
@@ -14,38 +15,55 @@ INSERT INTO sample_tbl SELECT * FROM generate_series(3, 4);
-- ===================================================================
-- Tests for input validation
-- ===================================================================
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_records_info(:'wal_lsn2', :'wal_lsn1'); -- ERROR
+-- Invalid input LSN or LSN that server doesn't have WAL for
+SELECT * FROM pg_get_wal_record_info('0/0'); -- ERROR
+ERROR: could not read WAL at LSN 0/0
+-- Invalid start LSN or start LSN that server doesn't have WAL for
+SELECT * FROM pg_get_wal_records_info('0/0', :'wal_lsn1'); -- ERROR
+ERROR: could not read WAL at LSN 0/0
+SELECT * FROM pg_get_wal_stats('0/0', :'wal_lsn1'); -- ERROR
+ERROR: could not read WAL at LSN 0/0
+SELECT * FROM pg_get_wal_block_info('0/0', :'wal_lsn1'); -- ERROR
+ERROR: could not read WAL at LSN 0/0
+-- Start LSN >= End LSN
+SELECT * FROM pg_get_wal_records_info(:'wal_lsn2', :'wal_lsn1'); -- ERROR
ERROR: WAL start LSN must be less than end LSN
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_stats(:'wal_lsn2', :'wal_lsn1'); -- ERROR
+SELECT * FROM pg_get_wal_stats(:'wal_lsn2', :'wal_lsn1'); -- ERROR
+ERROR: WAL start LSN must be less than end LSN
+SELECT * FROM pg_get_wal_block_info(:'wal_lsn2', :'wal_lsn1'); -- ERROR
ERROR: WAL start LSN must be less than end LSN
-- ===================================================================
-- Tests for all function executions
-- ===================================================================
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_record_info(:'wal_lsn1');
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_record_info(:'wal_lsn1');
ok
----
t
(1 row)
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_records_info(:'wal_lsn1', :'wal_lsn2');
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_records_info(:'wal_lsn1', :'wal_lsn2');
ok
----
t
(1 row)
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_records_info_till_end_of_wal(:'wal_lsn1');
+-- Get info till end of WAL. End LSN is way higher, adjust it to the latest LSN
+-- that server knows.
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_records_info(:'wal_lsn1', 'FFFFFFFF/FFFFFFFF');
ok
----
t
(1 row)
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_stats(:'wal_lsn1', :'wal_lsn2');
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_stats(:'wal_lsn1', :'wal_lsn2');
ok
----
t
(1 row)
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_stats_till_end_of_wal(:'wal_lsn1');
+-- Get info till end of WAL. End LSN is way higher, adjust it to the latest LSN
+-- that server knows.
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_stats(:'wal_lsn1', 'FFFFFFFF/FFFFFFFF');
ok
----
t
@@ -64,7 +82,7 @@ SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_records_info(:'wal_lsn1', :'wal_lsn2'
-- ===================================================================
-- Test for filtering out WAL records based on resource_manager and
--- record_type
+-- record_type.
-- ===================================================================
SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_records_info(:'wal_lsn1', :'wal_lsn2')
WHERE resource_manager = 'Heap' AND record_type = 'INSERT';
@@ -80,7 +98,7 @@ SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_records_info(:'wal_lsn1', :'wal_lsn2'
SELECT pg_current_wal_lsn() AS wal_lsn3 \gset
UPDATE sample_tbl SET col1 = col1 + 1 WHERE col1 = 1;
SELECT pg_current_wal_lsn() AS wal_lsn4 \gset
--- Check if we get block data from WAL record.
+-- Check if we get block data from WAL record
SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_block_info(:'wal_lsn3', :'wal_lsn4')
WHERE relfilenode = :'sample_tbl_oid' AND blockdata IS NOT NULL;
ok
@@ -88,12 +106,21 @@ SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_block_info(:'wal_lsn3', :'wal_lsn4')
t
(1 row)
--- Force full-page image on the next update.
+-- Check till end of WAL if we get block data from WAL record. End LSN is way
+-- higher, adjust it to the latest LSN that server knows.
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_block_info(:'wal_lsn3', 'FFFFFFFF/FFFFFFFF')
+ WHERE relfilenode = :'sample_tbl_oid';
+ ok
+----
+ t
+(1 row)
+
+-- Force full-page image on the next update
SELECT pg_current_wal_lsn() AS wal_lsn5 \gset
CHECKPOINT;
UPDATE sample_tbl SET col1 = col1 + 1 WHERE col1 = 2;
SELECT pg_current_wal_lsn() AS wal_lsn6 \gset
--- Check if we get FPI from WAL record.
+-- Check if we get FPI from WAL record
SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_block_info(:'wal_lsn5', :'wal_lsn6')
WHERE relfilenode = :'sample_tbl_oid' AND fpi IS NOT NULL;
ok
@@ -101,6 +128,15 @@ SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_block_info(:'wal_lsn5', :'wal_lsn6')
t
(1 row)
+-- Check till end of WAL if we get FPI from WAL record. End LSN is way higher,
+-- adjust it to the latest LSN that server knoows.
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_block_info(:'wal_lsn5', 'FFFFFFFF/FFFFFFFF')
+ WHERE relfilenode = :'sample_tbl_oid';
+ ok
+----
+ t
+(1 row)
+
-- ===================================================================
-- Tests for permissions
-- ===================================================================
diff --git a/contrib/pg_walinspect/meson.build b/contrib/pg_walinspect/meson.build
index bf7b79b1b7..80059f6119 100644
--- a/contrib/pg_walinspect/meson.build
+++ b/contrib/pg_walinspect/meson.build
@@ -30,6 +30,7 @@ tests += {
'regress': {
'sql': [
'pg_walinspect',
+ 'oldextversions',
],
# Disabled because these tests require "wal_level=replica", which
# some runningcheck users do not have (e.g. buildfarm clients).
diff --git a/contrib/pg_walinspect/pg_walinspect--1.0--1.1.sql b/contrib/pg_walinspect/pg_walinspect--1.0--1.1.sql
index e674ef25aa..a9c9ddda0e 100644
--- a/contrib/pg_walinspect/pg_walinspect--1.0--1.1.sql
+++ b/contrib/pg_walinspect/pg_walinspect--1.0--1.1.sql
@@ -3,6 +3,10 @@
-- complain if script is sourced in psql, rather than via ALTER EXTENSION
\echo Use "ALTER EXTENSION pg_walinspect UPDATE TO '1.1'" to load this file. \quit
+/* Drop the unneeded functions */
+DROP FUNCTION pg_get_wal_records_info_till_end_of_wal(pg_lsn);
+DROP FUNCTION pg_get_wal_stats_till_end_of_wal(pg_lsn, boolean);
+
--
-- pg_get_wal_block_info()
--
diff --git a/contrib/pg_walinspect/pg_walinspect.c b/contrib/pg_walinspect/pg_walinspect.c
index ee88dc4992..f604112623 100644
--- a/contrib/pg_walinspect/pg_walinspect.c
+++ b/contrib/pg_walinspect/pg_walinspect.c
@@ -38,15 +38,14 @@ PG_FUNCTION_INFO_V1(pg_get_wal_records_info_till_end_of_wal);
PG_FUNCTION_INFO_V1(pg_get_wal_stats);
PG_FUNCTION_INFO_V1(pg_get_wal_stats_till_end_of_wal);
-static bool IsFutureLSN(XLogRecPtr lsn, XLogRecPtr *curr_lsn);
+static XLogRecPtr GetCurrentLSN(void);
static XLogReaderState *InitXLogReaderState(XLogRecPtr lsn);
static XLogRecord *ReadNextXLogRecord(XLogReaderState *xlogreader);
static void GetWALRecordInfo(XLogReaderState *record, Datum *values,
bool *nulls, uint32 ncols);
-static XLogRecPtr ValidateInputLSNs(bool till_end_of_wal,
- XLogRecPtr start_lsn, XLogRecPtr end_lsn);
-static void GetWALRecordsInfo(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
- XLogRecPtr end_lsn);
+static void GetInputLSNs(FunctionCallInfo fcinfo, XLogRecPtr *start_lsn,
+ XLogRecPtr *end_lsn, bool till_end_of_wal);
+static void GetWALRecordsInfo(FunctionCallInfo fcinfo, bool till_end_of_wal);
static void GetXLogSummaryStats(XLogStats *stats, ReturnSetInfo *rsinfo,
Datum *values, bool *nulls, uint32 ncols,
bool stats_per_record);
@@ -55,32 +54,29 @@ static void FillXLogStatsRow(const char *name, uint64 n, uint64 total_count,
uint64 fpi_len, uint64 total_fpi_len,
uint64 tot_len, uint64 total_len,
Datum *values, bool *nulls, uint32 ncols);
-static void GetWalStats(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
- XLogRecPtr end_lsn, bool stats_per_record);
+static void GetWalStats(FunctionCallInfo fcinfo, bool till_end_of_wal);
static void GetWALBlockInfo(FunctionCallInfo fcinfo, XLogReaderState *record);
/*
- * Check if the given LSN is in future. Also, return the LSN up to which the
- * server has WAL.
+ * Return the LSN up to which the server has WAL.
*/
-static bool
-IsFutureLSN(XLogRecPtr lsn, XLogRecPtr *curr_lsn)
+static XLogRecPtr
+GetCurrentLSN(void)
{
+ XLogRecPtr curr_lsn;
+
/*
* We determine the current LSN of the server similar to how page_read
* callback read_local_xlog_page_no_wait does.
*/
if (!RecoveryInProgress())
- *curr_lsn = GetFlushRecPtr(NULL);
+ curr_lsn = GetFlushRecPtr(NULL);
else
- *curr_lsn = GetXLogReplayRecPtr(NULL);
+ curr_lsn = GetXLogReplayRecPtr(NULL);
- Assert(!XLogRecPtrIsInvalid(*curr_lsn));
+ Assert(!XLogRecPtrIsInvalid(curr_lsn));
- if (lsn >= *curr_lsn)
- return true;
-
- return false;
+ return curr_lsn;
}
/*
@@ -355,8 +351,13 @@ GetWALBlockInfo(FunctionCallInfo fcinfo, XLogReaderState *record)
* to a record. Decompression is applied to the full page images, if
* necessary.
*
- * This function emits an error if a future start or end WAL LSN i.e. WAL LSN
- * the database system doesn't know about is specified.
+ * This function emits an error if the start LSN is in future i.e. LSN the
+ * database system doesn't know about.
+ *
+ * This function adjusts future end LSN to the last flushed LSN when not in
+ * recovery or the last replayed LSN when in recovery.
+ *
+ * This function emits an error, if start LSN is past the end LSN.
*/
Datum
pg_get_wal_block_info(PG_FUNCTION_ARGS)
@@ -367,10 +368,7 @@ pg_get_wal_block_info(PG_FUNCTION_ARGS)
MemoryContext old_cxt;
MemoryContext tmp_cxt;
- start_lsn = PG_GETARG_LSN(0);
- end_lsn = PG_GETARG_LSN(1);
-
- end_lsn = ValidateInputLSNs(false, start_lsn, end_lsn);
+ GetInputLSNs(fcinfo, &start_lsn, &end_lsn, false);
InitMaterializedSRF(fcinfo, 0);
@@ -405,8 +403,8 @@ pg_get_wal_block_info(PG_FUNCTION_ARGS)
/*
* Get WAL record info.
*
- * This function emits an error if a future WAL LSN i.e. WAL LSN the database
- * system doesn't know about is specified.
+ * This function emits an error if input LSN is in future i.e. LSN the database
+ * system doesn't know about.
*/
Datum
pg_get_wal_record_info(PG_FUNCTION_ARGS)
@@ -422,20 +420,14 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
HeapTuple tuple;
lsn = PG_GETARG_LSN(0);
+ curr_lsn = GetCurrentLSN();
- if (IsFutureLSN(lsn, &curr_lsn))
- {
- /*
- * GetFlushRecPtr or GetXLogReplayRecPtr gives "end+1" LSN of the last
- * record flushed or replayed respectively. But let's use the LSN up
- * to "end" in user facing message.
- */
+ if (lsn >= curr_lsn)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot accept future input LSN"),
errdetail("Last known WAL LSN on the database system is at %X/%X.",
LSN_FORMAT_ARGS(curr_lsn))));
- }
/* Build a tuple descriptor for our result type. */
if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
@@ -462,54 +454,54 @@ pg_get_wal_record_info(PG_FUNCTION_ARGS)
}
/*
- * Validate the input LSNs and compute end LSN for till_end_of_wal versions.
+ * Get start and end LSN. Adjust end LSN if needed.
*/
-static XLogRecPtr
-ValidateInputLSNs(bool till_end_of_wal, XLogRecPtr start_lsn,
- XLogRecPtr end_lsn)
+static void
+GetInputLSNs(FunctionCallInfo fcinfo, XLogRecPtr *start_lsn,
+ XLogRecPtr *end_lsn, bool till_end_of_wal)
{
XLogRecPtr curr_lsn;
- if (IsFutureLSN(start_lsn, &curr_lsn))
- {
- /*
- * GetFlushRecPtr or GetXLogReplayRecPtr gives "end+1" LSN of the last
- * record flushed or replayed respectively. But let's use the LSN up
- * to "end" in user facing message.
- */
+ *start_lsn = PG_GETARG_LSN(0);
+ curr_lsn = GetCurrentLSN();
+
+ if (*start_lsn > curr_lsn)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot accept future start LSN"),
errdetail("Last known WAL LSN on the database system is at %X/%X.",
LSN_FORMAT_ARGS(curr_lsn))));
- }
if (till_end_of_wal)
- end_lsn = curr_lsn;
+ *end_lsn = curr_lsn;
+ else
+ {
+ *end_lsn = PG_GETARG_LSN(1);
- if (end_lsn > curr_lsn)
- ereport(ERROR,
- (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
- errmsg("cannot accept future end LSN"),
- errdetail("Last known WAL LSN on the database system is at %X/%X.",
- LSN_FORMAT_ARGS(curr_lsn))));
+ /*
+ * Adjust end LSN to what the system knows at this point instead of
+ * raising errors. This helps to achieve till end of WAL functionality.
+ */
+ if (*end_lsn > curr_lsn)
+ *end_lsn = curr_lsn;
+ }
- if (start_lsn >= end_lsn)
+ /* Return false, when start LSN is past the end LSN. */
+ if (*start_lsn >= *end_lsn)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("WAL start LSN must be less than end LSN")));
-
- return end_lsn;
}
/*
* Get info and data of all WAL records between start LSN and end LSN.
*/
static void
-GetWALRecordsInfo(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
- XLogRecPtr end_lsn)
+GetWALRecordsInfo(FunctionCallInfo fcinfo, bool till_end_of_wal)
{
#define PG_GET_WAL_RECORDS_INFO_COLS 11
+ XLogRecPtr start_lsn;
+ XLogRecPtr end_lsn;
XLogReaderState *xlogreader;
ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
Datum values[PG_GET_WAL_RECORDS_INFO_COLS] = {0};
@@ -517,6 +509,8 @@ GetWALRecordsInfo(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
MemoryContext old_cxt;
MemoryContext tmp_cxt;
+ GetInputLSNs(fcinfo, &start_lsn, &end_lsn, till_end_of_wal);
+
InitMaterializedSRF(fcinfo, 0);
xlogreader = InitXLogReaderState(start_lsn);
@@ -554,42 +548,18 @@ GetWALRecordsInfo(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
/*
* Get info and data of all WAL records between start LSN and end LSN.
*
- * This function emits an error if a future start or end WAL LSN i.e. WAL LSN
- * the database system doesn't know about is specified.
- */
-Datum
-pg_get_wal_records_info(PG_FUNCTION_ARGS)
-{
- XLogRecPtr start_lsn;
- XLogRecPtr end_lsn;
-
- start_lsn = PG_GETARG_LSN(0);
- end_lsn = PG_GETARG_LSN(1);
-
- end_lsn = ValidateInputLSNs(false, start_lsn, end_lsn);
-
- GetWALRecordsInfo(fcinfo, start_lsn, end_lsn);
-
- PG_RETURN_VOID();
-}
-
-/*
- * Get info and data of all WAL records from start LSN till end of WAL.
+ * This function emits an error if the start LSN is in future i.e. LSN the
+ * database system doesn't know about.
+ *
+ * This function adjusts future end LSN to the last flushed LSN when not in
+ * recovery or the last replayed LSN when in recovery.
*
- * This function emits an error if a future start i.e. WAL LSN the database
- * system doesn't know about is specified.
+ * This function emits an error, if start LSN is past the end LSN.
*/
Datum
-pg_get_wal_records_info_till_end_of_wal(PG_FUNCTION_ARGS)
+pg_get_wal_records_info(PG_FUNCTION_ARGS)
{
- XLogRecPtr start_lsn;
- XLogRecPtr end_lsn = InvalidXLogRecPtr;
-
- start_lsn = PG_GETARG_LSN(0);
-
- end_lsn = ValidateInputLSNs(true, start_lsn, end_lsn);
-
- GetWALRecordsInfo(fcinfo, start_lsn, end_lsn);
+ GetWALRecordsInfo(fcinfo, false);
PG_RETURN_VOID();
}
@@ -757,16 +727,22 @@ GetXLogSummaryStats(XLogStats *stats, ReturnSetInfo *rsinfo,
* Get WAL stats between start LSN and end LSN.
*/
static void
-GetWalStats(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
- XLogRecPtr end_lsn, bool stats_per_record)
+GetWalStats(FunctionCallInfo fcinfo, bool till_end_of_wal)
{
#define PG_GET_WAL_STATS_COLS 9
+ XLogRecPtr start_lsn;
+ XLogRecPtr end_lsn;
+ bool stats_per_record;
XLogReaderState *xlogreader;
XLogStats stats = {0};
ReturnSetInfo *rsinfo = (ReturnSetInfo *) fcinfo->resultinfo;
Datum values[PG_GET_WAL_STATS_COLS] = {0};
bool nulls[PG_GET_WAL_STATS_COLS] = {0};
+ GetInputLSNs(fcinfo, &start_lsn, &end_lsn, till_end_of_wal);
+
+ stats_per_record = PG_GETARG_BOOL(2);
+
InitMaterializedSRF(fcinfo, 0);
xlogreader = InitXLogReaderState(start_lsn);
@@ -792,46 +768,49 @@ GetWalStats(FunctionCallInfo fcinfo, XLogRecPtr start_lsn,
/*
* Get stats of all WAL records between start LSN and end LSN.
*
- * This function emits an error if a future start or end WAL LSN i.e. WAL LSN
- * the database system doesn't know about is specified.
+ * This function emits an error if the start LSN is in future i.e. LSN the
+ * database system doesn't know about.
+ *
+ * This function adjusts future end LSN to the last flushed LSN when not in
+ * recovery or the last replayed LSN when in recovery.
+ *
+ * This function emits an error, if start LSN is past the end LSN.
*/
Datum
pg_get_wal_stats(PG_FUNCTION_ARGS)
{
- XLogRecPtr start_lsn;
- XLogRecPtr end_lsn;
- bool stats_per_record;
-
- start_lsn = PG_GETARG_LSN(0);
- end_lsn = PG_GETARG_LSN(1);
- stats_per_record = PG_GETARG_BOOL(2);
-
- end_lsn = ValidateInputLSNs(false, start_lsn, end_lsn);
-
- GetWalStats(fcinfo, start_lsn, end_lsn, stats_per_record);
+ GetWalStats(fcinfo, false);
PG_RETURN_VOID();
}
/*
- * Get stats of all WAL records from start LSN till end of WAL.
+ * NB: Following till_end_of_wal functions have been removed in newer versions
+ * of extension. However, we keep them around for backward compatibility. Which
+ * means, these functions work if someone explicitly installs the older
+ * extension version (using CREATE EXTENSION pg_walinspect WITH VERSION '1.0';)
+ * containing them.
*
- * This function emits an error if a future start i.e. WAL LSN the database
- * system doesn't know about is specified.
+ * If definitions of these functions are removed completely, the extension
+ * fails to install. XXX: We might consider removing them eventually after
+ * enough extension versions are out and we do away with version '1.0'
+ * completely.
+ *
+ * In newer versions, one can use pg_get_wal_records_info()/pg_get_wal_stats()
+ * for the same till_end_of_wal functionality.
*/
Datum
-pg_get_wal_stats_till_end_of_wal(PG_FUNCTION_ARGS)
+pg_get_wal_records_info_till_end_of_wal(PG_FUNCTION_ARGS)
{
- XLogRecPtr start_lsn;
- XLogRecPtr end_lsn = InvalidXLogRecPtr;
- bool stats_per_record;
+ GetWALRecordsInfo(fcinfo, true);
- start_lsn = PG_GETARG_LSN(0);
- stats_per_record = PG_GETARG_BOOL(1);
-
- end_lsn = ValidateInputLSNs(true, start_lsn, end_lsn);
+ PG_RETURN_VOID();
+}
- GetWalStats(fcinfo, start_lsn, end_lsn, stats_per_record);
+Datum
+pg_get_wal_stats_till_end_of_wal(PG_FUNCTION_ARGS)
+{
+ GetWalStats(fcinfo, true);
PG_RETURN_VOID();
}
diff --git a/contrib/pg_walinspect/sql/oldextversions.sql b/contrib/pg_walinspect/sql/oldextversions.sql
new file mode 100644
index 0000000000..79a382acb4
--- /dev/null
+++ b/contrib/pg_walinspect/sql/oldextversions.sql
@@ -0,0 +1,29 @@
+-- test old extension version entry points
+
+DROP EXTENSION pg_walinspect;
+CREATE EXTENSION pg_walinspect WITH VERSION '1.0';
+
+-- List what version 1.0 contains
+\dx+ pg_walinspect
+
+-- ===================================================================
+-- Tests to check if the removed functions work when older version of
+-- extension is explicitly installed.
+-- ===================================================================
+-- Make sure checkpoints don't interfere with the test.
+SELECT 'init' FROM pg_create_physical_replication_slot('regress_pg_walinspect_slot', true, false);
+
+CREATE TABLE sample_tbl(col1 int, col2 int);
+SELECT pg_current_wal_lsn() AS wal_lsn1 \gset
+INSERT INTO sample_tbl SELECT * FROM generate_series(1, 2);
+
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_records_info_till_end_of_wal(:'wal_lsn1');
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_stats_till_end_of_wal(:'wal_lsn1');
+
+-- Move to new version 1.1
+ALTER EXTENSION pg_walinspect UPDATE TO '1.1';
+
+-- List what version 1.1 contains
+\dx+ pg_walinspect
+
+DROP EXTENSION pg_walinspect;
diff --git a/contrib/pg_walinspect/sql/pg_walinspect.sql b/contrib/pg_walinspect/sql/pg_walinspect.sql
index 01a120f398..8f2cdd09f9 100644
--- a/contrib/pg_walinspect/sql/pg_walinspect.sql
+++ b/contrib/pg_walinspect/sql/pg_walinspect.sql
@@ -1,77 +1,88 @@
CREATE EXTENSION pg_walinspect;
--- Make sure checkpoints don't interfere with the test.
+-- Make sure checkpoints don't interfere with the test
SELECT 'init' FROM pg_create_physical_replication_slot('regress_pg_walinspect_slot', true, false);
+-- Generate WAL and captures LSNs as needed
CREATE TABLE sample_tbl(col1 int, col2 int);
-
SELECT pg_current_wal_lsn() AS wal_lsn1 \gset
-
INSERT INTO sample_tbl SELECT * FROM generate_series(1, 2);
-
SELECT pg_current_wal_lsn() AS wal_lsn2 \gset
-
INSERT INTO sample_tbl SELECT * FROM generate_series(3, 4);
-- ===================================================================
-- Tests for input validation
-- ===================================================================
+-- Invalid input LSN or LSN that server doesn't have WAL for
+SELECT * FROM pg_get_wal_record_info('0/0'); -- ERROR
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_records_info(:'wal_lsn2', :'wal_lsn1'); -- ERROR
+-- Invalid start LSN or start LSN that server doesn't have WAL for
+SELECT * FROM pg_get_wal_records_info('0/0', :'wal_lsn1'); -- ERROR
+SELECT * FROM pg_get_wal_stats('0/0', :'wal_lsn1'); -- ERROR
+SELECT * FROM pg_get_wal_block_info('0/0', :'wal_lsn1'); -- ERROR
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_stats(:'wal_lsn2', :'wal_lsn1'); -- ERROR
+-- Start LSN >= End LSN
+SELECT * FROM pg_get_wal_records_info(:'wal_lsn2', :'wal_lsn1'); -- ERROR
+SELECT * FROM pg_get_wal_stats(:'wal_lsn2', :'wal_lsn1'); -- ERROR
+SELECT * FROM pg_get_wal_block_info(:'wal_lsn2', :'wal_lsn1'); -- ERROR
-- ===================================================================
-- Tests for all function executions
-- ===================================================================
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_record_info(:'wal_lsn1');
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_records_info(:'wal_lsn1', :'wal_lsn2');
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_record_info(:'wal_lsn1');
+-- Get info till end of WAL. End LSN is way higher, adjust it to the latest LSN
+-- that server knows.
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_records_info(:'wal_lsn1', 'FFFFFFFF/FFFFFFFF');
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_records_info(:'wal_lsn1', :'wal_lsn2');
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_stats(:'wal_lsn1', :'wal_lsn2');
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_records_info_till_end_of_wal(:'wal_lsn1');
-
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_stats(:'wal_lsn1', :'wal_lsn2');
-
-SELECT COUNT(*) >= 0 AS ok FROM pg_get_wal_stats_till_end_of_wal(:'wal_lsn1');
+-- Get info till end of WAL. End LSN is way higher, adjust it to the latest LSN
+-- that server knows.
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_stats(:'wal_lsn1', 'FFFFFFFF/FFFFFFFF');
-- ===================================================================
-- Test for filtering out WAL records of a particular table
-- ===================================================================
-
SELECT oid AS sample_tbl_oid FROM pg_class WHERE relname = 'sample_tbl' \gset
-
SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_records_info(:'wal_lsn1', :'wal_lsn2')
WHERE block_ref LIKE concat('%', :'sample_tbl_oid', '%') AND resource_manager = 'Heap';
-- ===================================================================
-- Test for filtering out WAL records based on resource_manager and
--- record_type
+-- record_type.
-- ===================================================================
-
SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_records_info(:'wal_lsn1', :'wal_lsn2')
WHERE resource_manager = 'Heap' AND record_type = 'INSERT';
-- ===================================================================
-- Tests to get block information from WAL record
-- ===================================================================
-
-- Update table to generate some block data
SELECT pg_current_wal_lsn() AS wal_lsn3 \gset
UPDATE sample_tbl SET col1 = col1 + 1 WHERE col1 = 1;
SELECT pg_current_wal_lsn() AS wal_lsn4 \gset
--- Check if we get block data from WAL record.
+-- Check if we get block data from WAL record
SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_block_info(:'wal_lsn3', :'wal_lsn4')
WHERE relfilenode = :'sample_tbl_oid' AND blockdata IS NOT NULL;
+-- Check till end of WAL if we get block data from WAL record. End LSN is way
+-- higher, adjust it to the latest LSN that server knows.
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_block_info(:'wal_lsn3', 'FFFFFFFF/FFFFFFFF')
+ WHERE relfilenode = :'sample_tbl_oid';
--- Force full-page image on the next update.
+-- Force full-page image on the next update
SELECT pg_current_wal_lsn() AS wal_lsn5 \gset
CHECKPOINT;
UPDATE sample_tbl SET col1 = col1 + 1 WHERE col1 = 2;
SELECT pg_current_wal_lsn() AS wal_lsn6 \gset
--- Check if we get FPI from WAL record.
+-- Check if we get FPI from WAL record
SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_block_info(:'wal_lsn5', :'wal_lsn6')
WHERE relfilenode = :'sample_tbl_oid' AND fpi IS NOT NULL;
+-- Check till end of WAL if we get FPI from WAL record. End LSN is way higher,
+-- adjust it to the latest LSN that server knoows.
+SELECT COUNT(*) >= 1 AS ok FROM pg_get_wal_block_info(:'wal_lsn5', 'FFFFFFFF/FFFFFFFF')
+ WHERE relfilenode = :'sample_tbl_oid';
-- ===================================================================
-- Tests for permissions
@@ -80,29 +91,22 @@ CREATE ROLE regress_pg_walinspect;
SELECT has_function_privilege('regress_pg_walinspect',
'pg_get_wal_record_info(pg_lsn)', 'EXECUTE'); -- no
-
SELECT has_function_privilege('regress_pg_walinspect',
'pg_get_wal_records_info(pg_lsn, pg_lsn) ', 'EXECUTE'); -- no
-
SELECT has_function_privilege('regress_pg_walinspect',
'pg_get_wal_stats(pg_lsn, pg_lsn, boolean) ', 'EXECUTE'); -- no
-
SELECT has_function_privilege('regress_pg_walinspect',
'pg_get_wal_block_info(pg_lsn, pg_lsn) ', 'EXECUTE'); -- no
-- Functions accessible by users with role pg_read_server_files
-
GRANT pg_read_server_files TO regress_pg_walinspect;
SELECT has_function_privilege('regress_pg_walinspect',
'pg_get_wal_record_info(pg_lsn)', 'EXECUTE'); -- yes
-
SELECT has_function_privilege('regress_pg_walinspect',
'pg_get_wal_records_info(pg_lsn, pg_lsn) ', 'EXECUTE'); -- yes
-
SELECT has_function_privilege('regress_pg_walinspect',
'pg_get_wal_stats(pg_lsn, pg_lsn, boolean) ', 'EXECUTE'); -- yes
-
SELECT has_function_privilege('regress_pg_walinspect',
'pg_get_wal_block_info(pg_lsn, pg_lsn) ', 'EXECUTE'); -- yes
@@ -111,46 +115,34 @@ REVOKE pg_read_server_files FROM regress_pg_walinspect;
-- Superuser can grant execute to other users
GRANT EXECUTE ON FUNCTION pg_get_wal_record_info(pg_lsn)
TO regress_pg_walinspect;
-
GRANT EXECUTE ON FUNCTION pg_get_wal_records_info(pg_lsn, pg_lsn)
TO regress_pg_walinspect;
-
GRANT EXECUTE ON FUNCTION pg_get_wal_stats(pg_lsn, pg_lsn, boolean)
TO regress_pg_walinspect;
-
GRANT EXECUTE ON FUNCTION pg_get_wal_block_info(pg_lsn, pg_lsn)
TO regress_pg_walinspect;
SELECT has_function_privilege('regress_pg_walinspect',
'pg_get_wal_record_info(pg_lsn)', 'EXECUTE'); -- yes
-
SELECT has_function_privilege('regress_pg_walinspect',
'pg_get_wal_records_info(pg_lsn, pg_lsn) ', 'EXECUTE'); -- yes
-
SELECT has_function_privilege('regress_pg_walinspect',
'pg_get_wal_stats(pg_lsn, pg_lsn, boolean) ', 'EXECUTE'); -- yes
-
SELECT has_function_privilege('regress_pg_walinspect',
'pg_get_wal_block_info(pg_lsn, pg_lsn) ', 'EXECUTE'); -- yes
REVOKE EXECUTE ON FUNCTION pg_get_wal_record_info(pg_lsn)
FROM regress_pg_walinspect;
-
REVOKE EXECUTE ON FUNCTION pg_get_wal_records_info(pg_lsn, pg_lsn)
FROM regress_pg_walinspect;
-
REVOKE EXECUTE ON FUNCTION pg_get_wal_stats(pg_lsn, pg_lsn, boolean)
FROM regress_pg_walinspect;
-
REVOKE EXECUTE ON FUNCTION pg_get_wal_block_info(pg_lsn, pg_lsn)
FROM regress_pg_walinspect;
-- ===================================================================
-- Clean up
-- ===================================================================
-
DROP ROLE regress_pg_walinspect;
-
SELECT pg_drop_replication_slot('regress_pg_walinspect_slot');
-
DROP TABLE sample_tbl;
diff --git a/doc/src/sgml/pgwalinspect.sgml b/doc/src/sgml/pgwalinspect.sgml
index 3b19863dce..d9aac121d5 100644
--- a/doc/src/sgml/pgwalinspect.sgml
+++ b/doc/src/sgml/pgwalinspect.sgml
@@ -61,8 +61,8 @@
Gets WAL record information of a given LSN. If the given LSN isn't
at the start of a WAL record, it gives the information of the next
available valid WAL record; or an error if no such record is found.
- For example, usage of the function is as
- follows:
+ It will raise an error, if given LSN is in future (i.e. the LSN server
+ doesn't know about). For example, usage of the function is as follows:
<screen>
postgres=# SELECT * FROM pg_get_wal_record_info('0/1E826E98');
-[ RECORD 1 ]----+----------------------------------------------------
@@ -85,7 +85,7 @@ block_ref | blkref #0: rel 1663/5/60221 fork main blk 2
<varlistentry id="pgwalinspect-funcs-pg-get-wal-records-info">
<term>
<function>
- pg_get_wal_records_info(start_lsn pg_lsn, end_lsn pg_lsn)
+ pg_get_wal_records_info(start_lsn pg_lsn, end_lsn pg_lsn DEFAULT NULL)
returns setof record
</function>
</term>
@@ -94,9 +94,13 @@ block_ref | blkref #0: rel 1663/5/60221 fork main blk 2
<para>
Gets information of all the valid WAL records between
<replaceable>start_lsn</replaceable> and <replaceable>end_lsn</replaceable>.
- Returns one row per WAL record. If <replaceable>start_lsn</replaceable>
- or <replaceable>end_lsn</replaceable> are not yet available, the
- function will raise an error. For example:
+ Returns one row per WAL record. If a future <replaceable>end_lsn</replaceable>
+ (i.e. the LSN server doesn't know about) is specified, it returns
+ informaton till end of WAL. It will raise an error, if the server
+ doesn't have WAL available at given <replaceable>start_lsn</replaceable>
+ or if the <replaceable>start_lsn</replaceable> is in future or is past
+ the <replaceable>end_lsn</replaceable>. For example, usage of the
+ function is as follows:
<screen>
postgres=# SELECT * FROM pg_get_wal_records_info('0/1E913618', '0/1E913740') LIMIT 1;
-[ RECORD 1 ]----+--------------------------------------------------------------
@@ -116,27 +120,10 @@ block_ref |
</listitem>
</varlistentry>
- <varlistentry id="pgwalinspect-funcs-pg-get-wal-records-info-till-end-of-wal">
- <term>
- <function>
- pg_get_wal_records_info_till_end_of_wal(start_lsn pg_lsn)
- returns setof record
- </function>
- </term>
-
- <listitem>
- <para>
- This function is the same as <function>pg_get_wal_records_info()</function>,
- except that it gets information of all the valid WAL records from
- <replaceable>start_lsn</replaceable> till the end of WAL.
- </para>
- </listitem>
- </varlistentry>
-
<varlistentry id="pgwalinspect-funcs-pg-get-wal-stats">
<term>
<function>
- pg_get_wal_stats(start_lsn pg_lsn, end_lsn pg_lsn, per_record boolean DEFAULT false)
+ pg_get_wal_stats(start_lsn pg_lsn, end_lsn pg_lsn DEFAULT NULL, per_record boolean DEFAULT false)
returns setof record
</function>
</term>
@@ -149,9 +136,13 @@ block_ref |
<replaceable>resource_manager</replaceable> type. When
<replaceable>per_record</replaceable> is set to <literal>true</literal>,
it returns one row per <replaceable>record_type</replaceable>.
- If <replaceable>start_lsn</replaceable>
- or <replaceable>end_lsn</replaceable> are not yet available, the
- function will raise an error. For example:
+ If a future <replaceable>end_lsn</replaceable> (i.e. the LSN server
+ doesn't know about) is specified, it returns stats till end of WAL. It
+ will raise an error, if the server doesn't have WAL available at given
+ <replaceable>start_lsn</replaceable> or if the
+ <replaceable>start_lsn</replaceable> is in future or is past the
+ <replaceable>end_lsn</replaceable>. For example, usage of the function is
+ as follows:
<screen>
postgres=# SELECT * FROM pg_get_wal_stats('0/1E847D00', '0/1E84F500')
WHERE count > 0 LIMIT 1 AND
@@ -171,23 +162,6 @@ combined_size_percentage | 2.8634072910530795
</listitem>
</varlistentry>
- <varlistentry id="pgwalinspect-funcs-pg-get-wal-stats-till-end-of-wal">
- <term>
- <function>
- pg_get_wal_stats_till_end_of_wal(start_lsn pg_lsn, per_record boolean DEFAULT false)
- returns setof record
- </function>
- </term>
-
- <listitem>
- <para>
- This function is the same as <function>pg_get_wal_stats()</function>,
- except that it gets statistics of all the valid WAL records from
- <replaceable>start_lsn</replaceable> till end of WAL.
- </para>
- </listitem>
- </varlistentry>
-
<varlistentry>
<term>
<function>pg_get_wal_block_info(start_lsn pg_lsn, end_lsn pg_lsn) returns setof record</function>
@@ -202,9 +176,13 @@ combined_size_percentage | 2.8634072910530795
and their information associated with all the valid WAL records between
<replaceable>start_lsn</replaceable> and
<replaceable>end_lsn</replaceable>. Returns one row per block registered
- in a WAL record. If <replaceable>start_lsn</replaceable> or
- <replaceable>end_lsn</replaceable> are not yet available, the function
- will raise an error. For example:
+ in a WAL record. If a future <replaceable>end_lsn</replaceable>
+ (i.e. the LSN server doesn't know about) is specified, it returns
+ information till end of WAL. It will raise an error, if the server
+ doesn't have WAL available at given <replaceable>start_lsn</replaceable>
+ or if the <replaceable>start_lsn</replaceable> is in future or is past
+ the <replaceable>end_lsn</replaceable>. For example, usage of the
+ function is as follows:
<screen>
postgres=# SELECT lsn, blockid, reltablespace, reldatabase, relfilenode,
relblocknumber, forkname,
@@ -227,8 +205,22 @@ fpiinfo | {HAS_HOLE,APPLY}
</para>
</listitem>
</varlistentry>
-
</variablelist>
+
+ <note>
+ <para>
+ Note that <function>pg_get_wal_records_info_till_end_of_wal</function> and
+ <function>pg_get_wal_stats_till_end_of_wal</function> functions have been
+ removed in the <filename>pg_walinspect</filename> version
+ <literal>1.1</literal>. The same functionality can be achieved with
+ <function>pg_get_wal_records_info</function> and
+ <function>pg_get_wal_stats</function> functions by specifying a future
+ <replaceable>end_lsn</replaceable>. However, <function>till_end_of_wal</function>
+ functions will still work if the extension is installed explicitly with
+ version <literal>1.0</literal>.
+ </para>
+ </note>
+
</sect2>
<sect2 id="pgwalinspect-author">
--
2.34.1
