From 2134a99b286c37fbdd6eee847b94abceeb28f7a2 Mon Sep 17 00:00:00 2001 From: Michael Paquier Date: Thu, 19 Jun 2025 13:09:09 +0900 Subject: [PATCH v1 11/12] Add new vartag_external for 8-byte TOAST values This is a new type of external TOAST pointer, able to be fed 8-byte TOAST values. It uses a dedicated vartag_external, which is used when a TOAST table uses bigint for its chunk_id. The relevant callbacks are added to toast_external.c. --- src/include/access/heaptoast.h | 8 ++- src/include/varatt.h | 31 ++++++++- src/backend/access/common/toast_external.c | 77 ++++++++++++++++++++- src/backend/access/common/toast_internals.c | 2 +- src/backend/access/heap/heaptoast.c | 2 +- doc/src/sgml/storage.sgml | 6 +- contrib/amcheck/verify_heapam.c | 2 +- 7 files changed, 119 insertions(+), 9 deletions(-) diff --git a/src/include/access/heaptoast.h b/src/include/access/heaptoast.h index 49c31b77e493..f72755a64dfe 100644 --- a/src/include/access/heaptoast.h +++ b/src/include/access/heaptoast.h @@ -81,6 +81,12 @@ #define EXTERN_TUPLE_MAX_SIZE MaximumBytesPerTuple(EXTERN_TUPLES_PER_PAGE) +#define TOAST_MAX_CHUNK_SIZE_INT8 \ + (EXTERN_TUPLE_MAX_SIZE - \ + MAXALIGN(SizeofHeapTupleHeader) - \ + (sizeof(uint32) * 2) - \ + sizeof(int32) - \ + VARHDRSZ) #define TOAST_MAX_CHUNK_SIZE_OID \ (EXTERN_TUPLE_MAX_SIZE - \ MAXALIGN(SizeofHeapTupleHeader) - \ @@ -89,7 +95,7 @@ VARHDRSZ) /* Maximum size of chunk possible for both types */ -#define TOAST_MAX_CHUNK_SIZE TOAST_MAX_CHUNK_SIZE_OID +#define TOAST_MAX_CHUNK_SIZE Max(TOAST_MAX_CHUNK_SIZE_INT8, TOAST_MAX_CHUNK_SIZE_OID) /* ---------- * heap_toast_insert_or_update - diff --git a/src/include/varatt.h b/src/include/varatt.h index 793030dae932..aa36e8e1f561 100644 --- a/src/include/varatt.h +++ b/src/include/varatt.h @@ -41,6 +41,29 @@ typedef struct varatt_external_oid Oid va_toastrelid; /* RelID of TOAST table containing it */ } varatt_external_oid; +/* + * struct varatt_external_int8 is a "larger" version of "TOAST pointer", + * that uses an 8-byte integer as value. + * + * This follows the same properties as varatt_external_oid, except that + * this is used in TOAST relations with int8 as attribute for chunk_id. + */ +typedef struct varatt_external_int8 +{ + int32 va_rawsize; /* Original data size (includes header) */ + uint32 va_extinfo; /* External saved size (without header) and + * compression method */ + /* + * Unique ID of value within TOAST table, as two uint32 for alignment + * and padding. + * XXX: think for example about the addition of an extra field for + * meta-data and/or more compression data, even if it's OK here). + */ + uint32 va_valueid_lo; + uint32 va_valueid_hi; + Oid va_toastrelid; /* RelID of TOAST table containing it */ +} varatt_external_int8; + /* * These macros define the "saved size" portion of va_extinfo. Its remaining @@ -91,6 +114,7 @@ typedef enum vartag_external VARTAG_INDIRECT = 1, VARTAG_EXPANDED_RO = 2, VARTAG_EXPANDED_RW = 3, + VARTAG_ONDISK_INT8 = 4, VARTAG_ONDISK_OID = 18 } vartag_external; @@ -102,6 +126,7 @@ typedef enum vartag_external ((tag) == VARTAG_INDIRECT ? sizeof(varatt_indirect) : \ VARTAG_IS_EXPANDED(tag) ? sizeof(varatt_expanded) : \ (tag) == VARTAG_ONDISK_OID ? sizeof(varatt_external_oid) : \ + (tag) == VARTAG_ONDISK_INT8 ? sizeof(varatt_external_int8) : \ (AssertMacro(false), 0)) /* @@ -294,8 +319,10 @@ typedef struct #define VARATT_IS_EXTERNAL(PTR) VARATT_IS_1B_E(PTR) #define VARATT_IS_EXTERNAL_ONDISK_OID(PTR) \ (VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_ONDISK_OID) +#define VARATT_IS_EXTERNAL_ONDISK_INT8(PTR) \ + (VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_ONDISK_INT8) #define VARATT_IS_EXTERNAL_ONDISK(PTR) \ - (VARATT_IS_EXTERNAL_ONDISK_OID(PTR)) + (VARATT_IS_EXTERNAL_ONDISK_OID(PTR) || VARATT_IS_EXTERNAL_ONDISK_INT8(PTR)) #define VARATT_IS_EXTERNAL_INDIRECT(PTR) \ (VARATT_IS_EXTERNAL(PTR) && VARTAG_EXTERNAL(PTR) == VARTAG_INDIRECT) #define VARATT_IS_EXTERNAL_EXPANDED_RO(PTR) \ @@ -339,7 +366,7 @@ typedef struct /* * Same for external Datums; but note argument is a struct - * varatt_external_oid. + * varatt_external_oid or varatt_external_int8. */ #define VARATT_EXTERNAL_GET_EXTSIZE(toast_pointer) \ ((toast_pointer).va_extinfo & VARLENA_EXTSIZE_MASK) diff --git a/src/backend/access/common/toast_external.c b/src/backend/access/common/toast_external.c index b6e8ff4facde..1f21dc699799 100644 --- a/src/backend/access/common/toast_external.c +++ b/src/backend/access/common/toast_external.c @@ -17,12 +17,23 @@ #include "access/heaptoast.h" #include "access/toast_external.h" +/* Callbacks for VARTAG_ONDISK_INT8 */ +static void ondisk_int8_to_external_data(struct varlena *attr, + toast_external_data *data); +static struct varlena *ondisk_int8_create_external_data(toast_external_data data); + /* Callbacks for VARTAG_ONDISK_OID */ static void ondisk_oid_to_external_data(struct varlena *attr, toast_external_data *data); static struct varlena *ondisk_oid_create_external_data(toast_external_data data); +/* + * Size of an EXTERNAL datum that contains a standard TOAST pointer + * (int8 value). + */ +#define TOAST_POINTER_INT8_SIZE (VARHDRSZ_EXTERNAL + sizeof(varatt_external_int8)) + /* * Size of an EXTERNAL datum that contains a standard TOAST pointer (OID * value). @@ -43,8 +54,14 @@ static struct varlena *ondisk_oid_create_external_data(toast_external_data data) * individual fields. */ static const toast_external_info toast_external_infos[TOAST_EXTERNAL_INFO_SIZE] = { + [VARTAG_ONDISK_INT8] = { + .toast_pointer_size = TOAST_POINTER_INT8_SIZE, + .maximum_chunk_size = TOAST_MAX_CHUNK_SIZE_INT8, + .to_external_data = ondisk_int8_to_external_data, + .create_external_data = ondisk_int8_create_external_data, + }, [VARTAG_ONDISK_OID] = { - .toast_pointer_size = TOAST_POINTER_OID_SIZE, + .toast_pointer_size = TOAST_POINTER_INT8_SIZE, .maximum_chunk_size = TOAST_MAX_CHUNK_SIZE_OID, .to_external_data = ondisk_oid_to_external_data, .create_external_data = ondisk_oid_create_external_data, @@ -70,7 +87,7 @@ toast_external_info_get_pointer_size(Oid toast_typid) if (toast_typid == OIDOID) return toast_external_infos[VARTAG_ONDISK_OID].toast_pointer_size; else if (toast_typid == INT8OID) - return toast_external_infos[VARTAG_ONDISK_OID].toast_pointer_size; + return toast_external_infos[VARTAG_ONDISK_INT8].toast_pointer_size; Assert(false); return 0; /* keep compiler quiet */ @@ -81,6 +98,62 @@ toast_external_info_get_pointer_size(Oid toast_typid) * the in-memory representation toast_external_data used in the backend. */ +/* Callbacks for VARTAG_ONDISK_INT8 */ +static void +ondisk_int8_to_external_data(struct varlena *attr, toast_external_data *data) +{ + varatt_external_int8 external; + + VARATT_EXTERNAL_GET_POINTER(external, attr); + data->rawsize = external.va_rawsize; + + /* External size and compression methods are stored in the same field */ + if (VARATT_EXTERNAL_IS_COMPRESSED(external)) + { + data->extsize = VARATT_EXTERNAL_GET_EXTSIZE(external); + data->compression_method = VARATT_EXTERNAL_GET_COMPRESS_METHOD(external); + } + else + { + data->extsize = external.va_extinfo; + data->compression_method = TOAST_INVALID_COMPRESSION_ID; + } + + data->value = (((uint64) external.va_valueid_hi) << 32) | + external.va_valueid_lo; + data->toastrelid = external.va_toastrelid; + +} + +static struct varlena * +ondisk_int8_create_external_data(toast_external_data data) +{ + struct varlena *result = NULL; + varatt_external_int8 external; + + external.va_rawsize = data.rawsize; + + if (data.compression_method != TOAST_INVALID_COMPRESSION_ID) + { + /* Set size and compression method, in a single field. */ + VARATT_EXTERNAL_SET_SIZE_AND_COMPRESS_METHOD(external, + data.extsize, + data.compression_method); + } + else + external.va_extinfo = data.extsize; + + external.va_toastrelid = data.toastrelid; + external.va_valueid_hi = (((uint64) data.value) >> 32); + external.va_valueid_lo = (uint32) data.value; + + result = (struct varlena *) palloc(TOAST_POINTER_INT8_SIZE); + SET_VARTAG_EXTERNAL(result, VARTAG_ONDISK_INT8); + memcpy(VARDATA_EXTERNAL(result), &external, sizeof(external)); + + return result; +} + /* Callbacks for VARTAG_ONDISK_OID */ static void ondisk_oid_to_external_data(struct varlena *attr, toast_external_data *data) diff --git a/src/backend/access/common/toast_internals.c b/src/backend/access/common/toast_internals.c index a7f29398ca9e..2e155f7f6b79 100644 --- a/src/backend/access/common/toast_internals.c +++ b/src/backend/access/common/toast_internals.c @@ -177,7 +177,7 @@ toast_save_datum(Relation rel, Datum value, if (toast_typid == OIDOID) tag = VARTAG_ONDISK_OID; else if (toast_typid == INT8OID) - tag = VARTAG_ONDISK_OID; + tag = VARTAG_ONDISK_INT8; info = toast_external_get_info(tag); /* Open all the toast indexes and look for the valid one */ diff --git a/src/backend/access/heap/heaptoast.c b/src/backend/access/heap/heaptoast.c index 6993aef2c2c3..fa132841c945 100644 --- a/src/backend/access/heap/heaptoast.c +++ b/src/backend/access/heap/heaptoast.c @@ -710,7 +710,7 @@ heap_fetch_toast_slice(Relation toastrel, uint64 valueid, int32 attrsize, if (toast_typid == OIDOID) tag = VARTAG_ONDISK_OID; else if (toast_typid == INT8OID) - tag = VARTAG_ONDISK_OID; + tag = VARTAG_ONDISK_INT8; info = toast_external_get_info(tag); max_chunk_size = info->maximum_chunk_size; diff --git a/doc/src/sgml/storage.sgml b/doc/src/sgml/storage.sgml index 564783a1c559..29ba80e8423c 100644 --- a/doc/src/sgml/storage.sgml +++ b/doc/src/sgml/storage.sgml @@ -415,7 +415,11 @@ described in more detail below. Out-of-line values are divided (after compression if used) into chunks of at -most TOAST_MAX_CHUNK_SIZE_OID bytes (by default this value is chosen +most TOAST_MAX_CHUNK_SIZE_OID bytes if the +TOAST relation uses the oid type for +chunk_id, or TOAST_MAX_CHUNK_SIZE_INT8 +bytes if the TOAST relation uses the int8 +type for chunk_id (by default these values are chosen so that four chunk rows will fit on a page, making it about 2000 bytes). Each chunk is stored as a separate row in the TOAST table belonging to the owning table. Every diff --git a/contrib/amcheck/verify_heapam.c b/contrib/amcheck/verify_heapam.c index 0898b6eea074..12e9ceb4d7ae 100644 --- a/contrib/amcheck/verify_heapam.c +++ b/contrib/amcheck/verify_heapam.c @@ -1733,7 +1733,7 @@ check_tuple_attribute(HeapCheckContext *ctx) { uint8 va_tag = VARTAG_EXTERNAL(tp + ctx->offset); - if (va_tag != VARTAG_ONDISK_OID) + if (va_tag != VARTAG_ONDISK_OID && va_tag != VARTAG_ONDISK_INT8) { report_corruption(ctx, psprintf("toasted attribute has unexpected TOAST tag %u", -- 2.49.0