From 8929d78e6b7e1266dec049319fe96688708b3ac3 Mon Sep 17 00:00:00 2001 From: Ashutosh Bapat Date: Thu, 26 Sep 2024 12:06:25 +0530 Subject: [PATCH 1/6] RestrictInfo hash table interface Introduces the RestrictInfo hash table interface and adds a pointer to RestrictInfo hash table in PlannerInfo. RestrictInfo::rinfo_serial and RestrictInfo::required_relids are used as key into the hash table. This commit does not add any code which uses the interface itself. Adding a new member to PlannerInfo increases it size and may have slight impact due to cacheline faults when accessing this huge structure. Similarly the interface code increases object file size which again may have some impact on performance. This is a separate commit to assess any performance or memory impact this change has. Ashutosh Bapat --- src/backend/optimizer/util/restrictinfo.c | 143 +++++++++++++++++++++- src/include/nodes/pathnodes.h | 3 + src/include/optimizer/restrictinfo.h | 3 + src/tools/pgindent/typedefs.list | 2 + 4 files changed, 150 insertions(+), 1 deletion(-) diff --git a/src/backend/optimizer/util/restrictinfo.c b/src/backend/optimizer/util/restrictinfo.c index 0b406e93342..7a6f73daf6d 100644 --- a/src/backend/optimizer/util/restrictinfo.c +++ b/src/backend/optimizer/util/restrictinfo.c @@ -19,7 +19,7 @@ #include "optimizer/clauses.h" #include "optimizer/optimizer.h" #include "optimizer/restrictinfo.h" - +#include "common/hashfn.h" static RestrictInfo *make_restrictinfo_internal(PlannerInfo *root, Expr *clause, @@ -685,3 +685,144 @@ join_clause_is_movable_into(RestrictInfo *rinfo, return true; } + +/* ---------------------------------------------------------------------------- + * RestrictInfo hash table interface. + * + * For storing and retrieving child RestrictInfos. Though the interface is used + * for child RestrictInfos, it can be used for parent RestrictInfos as well. + * Hence the names of functions and structures do not mention child in it unless + * necessary. + * + * RestrictInfo::rinfo_serial is unique for a set of RestrictInfos, all of + * which, are versions of same condition. RestrictInfo::required_relids + * identifies the relations to which the RestrictInfo is applicable. Together + * they are used as a key into the hash table since they uniquely identify a + * RestictInfo. + * ---------------------------------------------------------------------------- + */ + +/* + * Hash key for RestrictInfo hash table. + */ +typedef struct +{ + int rinfo_serial; /* Same as RestrictInfo::rinfo_serial */ + Relids required_relids; /* Same as RestrictInfo::required_relids */ +} rinfo_tab_key; + +/* Hash table entry for RestrictInfo hash table. */ +typedef struct rinfo_tab_entry +{ + rinfo_tab_key key; /* Key must be first. */ + RestrictInfo *rinfo; +} rinfo_tab_entry; + +/* + * rinfo_tab_key_hash + * Computes hash of RestrictInfo hash table key. + */ +static uint32 +rinfo_tab_key_hash(const void *key, Size size) +{ + rinfo_tab_key *rtabkey = (rinfo_tab_key *) key; + uint32 result; + + Assert(sizeof(rinfo_tab_key) == size); + + /* Combine hashes of all components of the key. */ + result = hash_bytes_uint32(rtabkey->rinfo_serial); + result = hash_combine(result, bms_hash_value(rtabkey->required_relids)); + + return result; +} + +/* + * rinfo_tab_key_match + * Match function for RestrictInfo hash table. + */ +static int +rinfo_tab_key_match(const void *key1, const void *key2, Size size) +{ + rinfo_tab_key *rtabkey1 = (rinfo_tab_key *) key1; + rinfo_tab_key *rtabkey2 = (rinfo_tab_key *) key2; + int result; + + Assert(sizeof(rinfo_tab_key) == size); + + result = rtabkey1->rinfo_serial - rtabkey2->rinfo_serial; + if (result) + return result; + + return !bms_equal(rtabkey1->required_relids, rtabkey2->required_relids); +} + +/* + * get_child_rinfo_hash + * Returns the child RestrictInfo hash table from PlannerInfo, creating it if + * necessary. + */ +static HTAB * +get_child_rinfo_hash(PlannerInfo *root) +{ + if (!root->child_rinfo_hash) + { + HASHCTL hash_ctl = {0}; + + hash_ctl.keysize = sizeof(rinfo_tab_key); + hash_ctl.entrysize = sizeof(rinfo_tab_entry); + hash_ctl.hcxt = root->planner_cxt; + hash_ctl.hash = rinfo_tab_key_hash; + hash_ctl.match = rinfo_tab_key_match; + + root->child_rinfo_hash = hash_create("restrictinfo hash table", + 1000, + &hash_ctl, + HASH_ELEM | HASH_CONTEXT | HASH_FUNCTION | HASH_COMPARE); + } + + return root->child_rinfo_hash; +} + +/* + * add_restrictinfo + * Add the given RestrictInfo to the RestrictInfo hash table. + */ +extern void +add_restrictinfo(PlannerInfo *root, RestrictInfo *rinfo) +{ + HTAB *rinfo_hash = get_child_rinfo_hash(root); + rinfo_tab_key key; + rinfo_tab_entry *rinfo_entry; + bool found; + + key.rinfo_serial = rinfo->rinfo_serial; + key.required_relids = rinfo->required_relids; + rinfo_entry = hash_search(rinfo_hash, &key, HASH_ENTER, &found); + + Assert(!found); + rinfo_entry->rinfo = rinfo; +} + +/* + * find_restrictinfo + * Return the RestrictInfo with given rinfo_serial and + * required_relids from RestrictInfo hash table. + * + * The function returns NULL if it does not find the required RestrictInfo in + * the hash table. + */ +RestrictInfo * +find_restrictinfo(PlannerInfo *root, int rinfo_serial, Relids required_relids) +{ + HTAB *rinfo_hash = get_child_rinfo_hash(root); + rinfo_tab_entry *rinfo_entry; + rinfo_tab_key key; + + key.rinfo_serial = rinfo_serial; + key.required_relids = required_relids; + rinfo_entry = hash_search(rinfo_hash, &key, + HASH_FIND, + NULL); + return (rinfo_entry ? rinfo_entry->rinfo : NULL); +} diff --git a/src/include/nodes/pathnodes.h b/src/include/nodes/pathnodes.h index 07e2415398e..fe48d7af20b 100644 --- a/src/include/nodes/pathnodes.h +++ b/src/include/nodes/pathnodes.h @@ -342,6 +342,9 @@ struct PlannerInfo /* counter for assigning RestrictInfo serial numbers */ int last_rinfo_serial; + /* Hash table to store and retrieve child RestrictInfos. */ + struct HTAB *child_rinfo_hash pg_node_attr(read_write_ignore); + /* * all_result_relids is empty for SELECT, otherwise it contains at least * parse->resultRelation. For UPDATE/DELETE/MERGE across an inheritance diff --git a/src/include/optimizer/restrictinfo.h b/src/include/optimizer/restrictinfo.h index 1b42c832c59..d2594fc5de4 100644 --- a/src/include/optimizer/restrictinfo.h +++ b/src/include/optimizer/restrictinfo.h @@ -47,5 +47,8 @@ extern bool join_clause_is_movable_to(RestrictInfo *rinfo, RelOptInfo *baserel); extern bool join_clause_is_movable_into(RestrictInfo *rinfo, Relids currentrelids, Relids current_and_outer); +extern RestrictInfo *find_restrictinfo(PlannerInfo *root, int rinfo_serial, + Relids child_required_relids); +extern void add_restrictinfo(PlannerInfo *root, RestrictInfo *child_rinfo); #endif /* RESTRICTINFO_H */ diff --git a/src/tools/pgindent/typedefs.list b/src/tools/pgindent/typedefs.list index a65e1c07c5d..915899225f5 100644 --- a/src/tools/pgindent/typedefs.list +++ b/src/tools/pgindent/typedefs.list @@ -3872,6 +3872,8 @@ rewind_source rewrite_event rf_context rfile +rinfo_tab_entry +rinfo_tab_key rm_detail_t role_auth_extra rolename_hash -- 2.34.1