timescale · mkindahl · Nov 13, 2024 · Oct 29, 2024
diff --git a/.unreleased/pr_7412 b/.unreleased/pr_7412
@@ -0,0 +1 @@
+Implements: #7412 Add GUC for hypercore_use_access_method default
diff --git a/src/guc.c b/src/guc.c
@@ -16,6 +16,7 @@
 #include "guc.h"
 #include "hypertable_cache.h"
 #include "license_guc.h"
+
 #ifdef USE_TELEMETRY
 #include "telemetry/telemetry.h"
 #endif
@@ -139,6 +140,7 @@ bool ts_guc_enable_custom_hashagg = false;
 TSDLLEXPORT bool ts_guc_enable_compression_indexscan = false;
 TSDLLEXPORT bool ts_guc_enable_bulk_decompression = true;
 TSDLLEXPORT bool ts_guc_auto_sparse_indexes = true;
+TSDLLEXPORT bool ts_guc_default_hypercore_use_access_method = false;
 bool ts_guc_enable_chunk_skipping = false;
 TSDLLEXPORT bool ts_guc_enable_segmentwise_recompression = true;
 
@@ -1117,6 +1119,18 @@ _guc_init(void)
 							 /* show_hook= */ NULL);
 #endif
 
+	DefineCustomBoolVariable(MAKE_EXTOPTION("default_hypercore_use_access_method"),
+							 gettext_noop("Enable to always use Hypercore TAM when compressing."),
+							 gettext_noop("Sets the global default for using Hypercore TAM when "
+										  "compressing chunks."),
+							 &ts_guc_default_hypercore_use_access_method,
+							 false,
+							 /* context= */ PGC_USERSET,
+							 /* flags= */ 0,
+							 /* check_hook= */ NULL,
+							 /* assign_hook= */ NULL,
+							 /* show_hook= */ NULL);
+
 	/* register feature flags */
 	ts_feature_flag_add(FEATURE_HYPERTABLE);
 	ts_feature_flag_add(FEATURE_HYPERTABLE_COMPRESSION);

diff --git a/src/guc.h b/src/guc.h
@@ -11,6 +11,21 @@
 #include "config.h"
 #include "export.h"
 
+/*
+ * Decide if the access method should be used for compression, or if it is
+ * undefined. Used for parameter values to PostgreSQL functions and is a
+ * nullable boolean.
+ *
+ * Using explicit values of TRUE = 1 and FALSE = 0 since this enum is cast to
+ * boolean value in the code.
+ */
+typedef enum UseAccessMethod
+{
+	USE_AM_FALSE = 0,
+	USE_AM_TRUE = 1,
+	USE_AM_NULL = 2,
+} UseAccessMethod;
+
 #ifdef USE_TELEMETRY
 extern bool ts_telemetry_on(void);
 extern bool ts_function_telemetry_on(void);
@@ -102,6 +117,7 @@ extern TSDLLEXPORT DebugRequireOption ts_guc_debug_require_vector_agg;
 
 extern TSDLLEXPORT bool ts_guc_debug_compression_path_info;
 extern TSDLLEXPORT bool ts_guc_enable_rowlevel_compression_locking;
+extern TSDLLEXPORT bool ts_guc_default_hypercore_use_access_method;
 
 extern TSDLLEXPORT bool ts_guc_debug_require_batch_sorted_merge;
 
@@ -121,4 +137,5 @@ typedef enum
 extern TSDLLEXPORT void ts_feature_flag_check(FeatureFlagType);
 extern TSDLLEXPORT Oid ts_guc_default_segmentby_fn_oid(void);
 extern TSDLLEXPORT Oid ts_guc_default_orderby_fn_oid(void);
+
 extern TSDLLEXPORT bool ts_is_whitelisted_indexam(const char *amname);
diff --git a/tsl/src/bgw_policy/compression_api.h b/tsl/src/bgw_policy/compression_api.h
@@ -6,10 +6,11 @@
 #pragma once
 
 #include <postgres.h>
-#include "compression/api.h"
 #include <utils/jsonb.h>
 #include <utils/timestamp.h>
 
+#include "guc.h"
+
 /* User-facing API functions */
 extern Datum policy_compression_add(PG_FUNCTION_ARGS);
 extern Datum policy_compression_remove(PG_FUNCTION_ARGS);

diff --git a/tsl/src/compression/api.c b/tsl/src/compression/api.c
@@ -838,13 +838,23 @@ compress_hypercore(Chunk *chunk, bool rel_is_hypercore, UseAccessMethod useam,
 	return relid;
 }
 
+/*
+ * Check the value of the use_access_method argument and use the default value
+ * otherwise.
+ */
+static UseAccessMethod
+check_useam(UseAccessMethod arg)
+{
+	return arg == USE_AM_NULL ? (UseAccessMethod) ts_guc_default_hypercore_use_access_method : arg;
+}
+
 Datum
 tsl_compress_chunk(PG_FUNCTION_ARGS)
 {
 	Oid uncompressed_chunk_id = PG_ARGISNULL(0) ? InvalidOid : PG_GETARG_OID(0);
 	bool if_not_compressed = PG_ARGISNULL(1) ? true : PG_GETARG_BOOL(1);
 	bool recompress = PG_ARGISNULL(2) ? false : PG_GETARG_BOOL(2);
-	UseAccessMethod useam = PG_ARGISNULL(3) ? USE_AM_NULL : PG_GETARG_BOOL(3);
+	UseAccessMethod useam = check_useam(PG_ARGISNULL(3) ? USE_AM_NULL : PG_GETARG_BOOL(3));
 
 	ts_feature_flag_check(FEATURE_HYPERTABLE_COMPRESSION);
 

diff --git a/tsl/src/compression/api.h b/tsl/src/compression/api.h
@@ -11,21 +11,6 @@
 
 #include "chunk.h"
 
-/*
- * Decide if the access method should be used for compression, or if it is
- * undefined. Used for parameter values to PostgreSQL functions and is a
- * nullable boolean.
- *
- * Using explicit values of TRUE = 1 and FALSE = 0 since this enum is cast to
- * boolean value in the code.
- */
-typedef enum UseAccessMethod
-{
-	USE_AM_FALSE = 0,
-	USE_AM_TRUE = 1,
-	USE_AM_NULL = 2,
-} UseAccessMethod;
-
 extern Datum tsl_create_compressed_chunk(PG_FUNCTION_ARGS);
 extern Datum tsl_compress_chunk(PG_FUNCTION_ARGS);
 extern Datum tsl_decompress_chunk(PG_FUNCTION_ARGS);

diff --git a/tsl/test/expected/hypercore.out b/tsl/test/expected/hypercore.out
@@ -521,6 +521,7 @@ SELECT sum(_ts_meta_count) FROM :cchunk;
 
 CALL recompress_chunk(:'chunk');
 WARNING:  procedure public.recompress_chunk(regclass,boolean) is deprecated and the functionality is now included in public.compress_chunk. this compatibility function will be removed in a future version.
+NOTICE:  cannot compress hypercore "_hyper_1_1_chunk" using heap, recompressing instead
 -- Data should be returned even after recompress, but now from the
 -- compressed relation. Still using index scan.
 EXPLAIN (verbose, costs off)
@@ -575,6 +576,7 @@ SELECT * FROM :chunk WHERE time = '2022-06-01 00:06:15'::timestamptz;
 -- Can't recompress twice without new non-compressed rows
 CALL recompress_chunk(:'chunk');
 WARNING:  procedure public.recompress_chunk(regclass,boolean) is deprecated and the functionality is now included in public.compress_chunk. this compatibility function will be removed in a future version.
+NOTICE:  cannot compress hypercore "_hyper_1_1_chunk" using heap, recompressing instead
 NOTICE:  chunk "_hyper_1_1_chunk" is already compressed
 \set ON_ERROR_STOP 1
 -- Compressed count after recompression

diff --git a/tsl/test/expected/hypercore_create.out b/tsl/test/expected/hypercore_create.out
@@ -691,6 +691,7 @@ select ctid from :chunk where created_at = '2022-06-01 10:01' and device_id = 6;
 (1 row)
 
 select compress_chunk(:'chunk');
+NOTICE:  cannot compress hypercore "_hyper_1_1_chunk" using heap, recompressing instead
              compress_chunk             
 ----------------------------------------
  _timescaledb_internal._hyper_1_1_chunk
@@ -921,3 +922,60 @@ select * from rides order by pickup_datetime;
  745233436676 | Fri Jan 01 00:00:03 2016 PST | Fri Jan 01 00:11:14 2016 PST |               1 |          6.00 | -73.947151184082031 | 40.791046142578125 |         1 | -73.920768737792969 | 40.865577697753906 |            2 |           9 |   0.5 |     0.5 |          0 |            0 |                   0.3 |         19.3
 (3 rows)
 
+-- All these are valid methods to set the default
+show timescaledb.default_hypercore_use_access_method;
+ timescaledb.default_hypercore_use_access_method 
+-------------------------------------------------
+ off
+(1 row)
+
+set timescaledb.default_hypercore_use_access_method to on;
+set timescaledb.default_hypercore_use_access_method to off;
+set timescaledb.default_hypercore_use_access_method to true;
+set timescaledb.default_hypercore_use_access_method to false;
+set timescaledb.default_hypercore_use_access_method to yes;
+set timescaledb.default_hypercore_use_access_method to no;
+set timescaledb.default_hypercore_use_access_method to 0;
+set timescaledb.default_hypercore_use_access_method to 1;
+show timescaledb.default_hypercore_use_access_method;
+ timescaledb.default_hypercore_use_access_method 
+-------------------------------------------------
+ on
+(1 row)
+
+-- This should unset the value
+reset timescaledb.default_hypercore_use_access_method;
+show timescaledb.default_hypercore_use_access_method;
+ timescaledb.default_hypercore_use_access_method 
+-------------------------------------------------
+ off
+(1 row)
+
+-- Using GUC should compress using the hyperstore
+set timescaledb.default_hypercore_use_access_method to on;
+create table test5 (time timestamptz not null, device int, temp float);
+select created from create_hypertable('test5', 'time');
+ created 
+---------
+ t
+(1 row)
+
+insert into test5 values ('2022-06-01', 1, 1.0), ('2022-08-01', 1, 1.0);
+select ch as chunk from show_chunks('test5') ch limit 1 \gset
+alter table test5 set (timescaledb.compress);
+WARNING:  there was some uncertainty picking the default segment by for the hypertable: You do not have any indexes on columns that can be used for segment_by and thus we are not using segment_by for compression. Please make sure you are not missing any indexes
+NOTICE:  default segment by for hypertable "test5" is set to ""
+NOTICE:  default order by for hypertable "test5" is set to ""time" DESC"
+select compress_chunk(:'chunk');
+              compress_chunk              
+------------------------------------------
+ _timescaledb_internal._hyper_10_46_chunk
+(1 row)
+
+select * from amrels where relparent = 'test5'::regclass;
+                   rel                    |  amname   | relparent 
+------------------------------------------+-----------+-----------
+ _timescaledb_internal._hyper_10_46_chunk | hypercore | test5
+ _timescaledb_internal._hyper_10_47_chunk | heap      | test5
+(2 rows)
+
diff --git a/tsl/test/expected/hypercore_vacuum.out b/tsl/test/expected/hypercore_vacuum.out
@@ -227,6 +227,7 @@ insert into hystable (time, location, device, temp)
 values ('2022-06-01 00:01', 1, 1, 1.0);
 -- Recompress to get data back into compressed form
 select compress_chunk(:'hystable_chunk');
+NOTICE:  cannot compress hypercore "_hyper_1_2_chunk" using heap, recompressing instead
              compress_chunk             
 ----------------------------------------
  _timescaledb_internal._hyper_1_2_chunk
@@ -310,6 +311,7 @@ select tuple_count from pgstattuple(:'hystable_device_chunk_idx');
 -- rebuild indexes. It will optimize the structure of the index and
 -- thus reduce the number of index tuples
 select compress_chunk(:'hystable_chunk');
+NOTICE:  cannot compress hypercore "_hyper_1_2_chunk" using heap, recompressing instead
              compress_chunk             
 ----------------------------------------
  _timescaledb_internal._hyper_1_2_chunk

diff --git a/tsl/test/sql/hypercore_create.sql b/tsl/test/sql/hypercore_create.sql
@@ -446,3 +446,30 @@ analyze rides;
 explain (costs off)
 select * from rides order by pickup_datetime;
 select * from rides order by pickup_datetime;
+
+-- All these are valid methods to set the default
+show timescaledb.default_hypercore_use_access_method;
+set timescaledb.default_hypercore_use_access_method to on;
+set timescaledb.default_hypercore_use_access_method to off;
+set timescaledb.default_hypercore_use_access_method to true;
+set timescaledb.default_hypercore_use_access_method to false;
+set timescaledb.default_hypercore_use_access_method to yes;
+set timescaledb.default_hypercore_use_access_method to no;
+set timescaledb.default_hypercore_use_access_method to 0;
+set timescaledb.default_hypercore_use_access_method to 1;
+show timescaledb.default_hypercore_use_access_method;
+
+-- This should unset the value
+reset timescaledb.default_hypercore_use_access_method;
+show timescaledb.default_hypercore_use_access_method;
+
+-- Using GUC should compress using the hyperstore
+set timescaledb.default_hypercore_use_access_method to on;
+create table test5 (time timestamptz not null, device int, temp float);
+select created from create_hypertable('test5', 'time');
+insert into test5 values ('2022-06-01', 1, 1.0), ('2022-08-01', 1, 1.0);
+
+select ch as chunk from show_chunks('test5') ch limit 1 \gset
+alter table test5 set (timescaledb.compress);
+select compress_chunk(:'chunk');
+select * from amrels where relparent = 'test5'::regclass;
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		Implements: #7412 Add GUC for hypercore_use_access_method default