You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
442 lines
14 KiB
442 lines
14 KiB
/*
|
|
Copyright (c) 2014, 2019, Oracle and/or its affiliates. All rights reserved.
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License, version 2.0,
|
|
as published by the Free Software Foundation.
|
|
|
|
This program is also distributed with certain software (including
|
|
but not limited to OpenSSL) that is licensed under separate terms,
|
|
as designated in a particular file or component or in included license
|
|
documentation. The authors of MySQL hereby grant you an additional
|
|
permission to link the program and your derivative works with the
|
|
separately licensed software that they have included with MySQL.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License, version 2.0, for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program; if not, write to the Free Software
|
|
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
|
|
|
|
#include "sql/opt_costconstantcache.h"
|
|
|
|
#include <memory>
|
|
|
|
#include "m_ctype.h"
|
|
#include "m_string.h"
|
|
#include "my_dbug.h"
|
|
#include "my_loglevel.h"
|
|
#include "mysql/components/services/log_builtins.h"
|
|
#include "mysql/components/services/log_shared.h"
|
|
#include "mysqld_error.h"
|
|
#include "sql/current_thd.h" // current_thd
|
|
#include "sql/field.h" // Field
|
|
#include "sql/mysqld.h" // key_LOCK_cost_const
|
|
#include "sql/records.h" // unique_ptr_destroy_only<RowIterator>
|
|
#include "sql/row_iterator.h"
|
|
#include "sql/sql_base.h" // open_and_lock_tables
|
|
#include "sql/sql_class.h" // THD
|
|
#include "sql/sql_const.h"
|
|
#include "sql/sql_lex.h" // lex_start/lex_end
|
|
#include "sql/sql_tmp_table.h" // init_cache_tmp_engine_properties
|
|
#include "sql/table.h" // TABLE
|
|
#include "sql/transaction.h" // trans_commit_stmt
|
|
#include "sql_string.h"
|
|
#include "template_utils.h" // pointer_cast
|
|
#include "thr_lock.h"
|
|
#include "thr_mutex.h"
|
|
|
|
Cost_constant_cache *cost_constant_cache = NULL;
|
|
|
|
static void read_cost_constants(Cost_model_constants *cost_constants);
|
|
|
|
/**
|
|
Minimal initialization of the object. The main initialization is done
|
|
by calling init().
|
|
*/
|
|
|
|
Cost_constant_cache::Cost_constant_cache()
|
|
: current_cost_constants(NULL), m_inited(false) {}
|
|
|
|
Cost_constant_cache::~Cost_constant_cache() {
|
|
// Verify that close has been called
|
|
DBUG_ASSERT(current_cost_constants == NULL);
|
|
DBUG_ASSERT(m_inited == false);
|
|
}
|
|
|
|
void Cost_constant_cache::init() {
|
|
DBUG_TRACE;
|
|
|
|
DBUG_ASSERT(m_inited == false);
|
|
|
|
// Initialize the mutex that is used for protecting the cost constants
|
|
mysql_mutex_init(key_LOCK_cost_const, &LOCK_cost_const, MY_MUTEX_INIT_FAST);
|
|
|
|
// Create cost constants from constants found in the source code
|
|
Cost_model_constants *cost_constants = create_defaults();
|
|
|
|
// Set this to be the current set of cost constants
|
|
update_current_cost_constants(cost_constants);
|
|
|
|
m_inited = true;
|
|
}
|
|
|
|
void Cost_constant_cache::close() {
|
|
DBUG_TRACE;
|
|
|
|
DBUG_ASSERT(m_inited);
|
|
|
|
if (m_inited == false) return; /* purecov: inspected */
|
|
|
|
// Release the current cost constant set
|
|
if (current_cost_constants) {
|
|
release_cost_constants(current_cost_constants);
|
|
current_cost_constants = NULL;
|
|
}
|
|
|
|
// To ensure none is holding the mutex when deleting it, lock/unlock it.
|
|
mysql_mutex_lock(&LOCK_cost_const);
|
|
mysql_mutex_unlock(&LOCK_cost_const);
|
|
|
|
mysql_mutex_destroy(&LOCK_cost_const);
|
|
|
|
m_inited = false;
|
|
}
|
|
|
|
void Cost_constant_cache::reload() {
|
|
DBUG_TRACE;
|
|
DBUG_ASSERT(m_inited = true);
|
|
|
|
// Create cost constants from the constants defined in the source code
|
|
Cost_model_constants *cost_constants = create_defaults();
|
|
|
|
// Update the cost constants from the database tables
|
|
read_cost_constants(cost_constants);
|
|
|
|
// Set this to be the current set of cost constants
|
|
update_current_cost_constants(cost_constants);
|
|
}
|
|
|
|
Cost_model_constants *Cost_constant_cache::create_defaults() const {
|
|
// Create default cost constants
|
|
Cost_model_constants *cost_constants = new Cost_model_constants();
|
|
|
|
return cost_constants;
|
|
}
|
|
|
|
void Cost_constant_cache::update_current_cost_constants(
|
|
Cost_model_constants *new_cost_constants) {
|
|
/*
|
|
Increase the ref counter to ensure that the new cost constants
|
|
are not deleted until next time we have a new set of cost constants.
|
|
*/
|
|
new_cost_constants->inc_ref_count();
|
|
|
|
/*
|
|
The mutex needs to be held for the entire period for removing the
|
|
current cost constants and adding the new cost constants to ensure
|
|
that no user of this class can access the object when there is no
|
|
current cost constants.
|
|
*/
|
|
mysql_mutex_lock(&LOCK_cost_const);
|
|
|
|
// Release the current cost constants by decrementing the ref counter
|
|
if (current_cost_constants) {
|
|
const unsigned int ref_count = current_cost_constants->dec_ref_count();
|
|
|
|
// If there is none using the current cost constants then delete them
|
|
if (ref_count == 0) delete current_cost_constants;
|
|
}
|
|
|
|
// Start to use the new cost constants
|
|
current_cost_constants = new_cost_constants;
|
|
|
|
mysql_mutex_unlock(&LOCK_cost_const);
|
|
}
|
|
|
|
/**
|
|
Write warnings about illegal entries in the server_cost table
|
|
|
|
The warnings are written to the MySQL error log.
|
|
|
|
@param cost_name name of the cost constant
|
|
@param value value it was attempted set to
|
|
@param error error status
|
|
*/
|
|
|
|
static void report_server_cost_warnings(const LEX_CSTRING &cost_name,
|
|
double value,
|
|
cost_constant_error error) {
|
|
switch (error) {
|
|
case UNKNOWN_COST_NAME:
|
|
LogErr(WARNING_LEVEL, ER_SERVER_COST_UNKNOWN_COST_CONSTANT,
|
|
cost_name.str);
|
|
break;
|
|
case INVALID_COST_VALUE:
|
|
LogErr(WARNING_LEVEL, ER_SERVER_COST_INVALID_COST_CONSTANT, cost_name.str,
|
|
value);
|
|
break;
|
|
default:
|
|
DBUG_ASSERT(false); /* purecov: inspected */
|
|
}
|
|
}
|
|
|
|
/**
|
|
Write warnings about illegal entries in the engine_cost table
|
|
|
|
The warnings are written to the MySQL error log.
|
|
|
|
@param se_name name of storage engine
|
|
@param storage_category device type
|
|
@param cost_name name of the cost constant
|
|
@param value value it was attempted set to
|
|
@param error error status
|
|
*/
|
|
|
|
static void report_engine_cost_warnings(const LEX_CSTRING &se_name,
|
|
int storage_category,
|
|
const LEX_CSTRING &cost_name,
|
|
double value,
|
|
cost_constant_error error) {
|
|
switch (error) {
|
|
case UNKNOWN_COST_NAME:
|
|
LogErr(WARNING_LEVEL, ER_ENGINE_COST_UNKNOWN_COST_CONSTANT,
|
|
cost_name.str);
|
|
break;
|
|
case UNKNOWN_ENGINE_NAME:
|
|
LogErr(WARNING_LEVEL, ER_ENGINE_COST_UNKNOWN_STORAGE_ENGINE, se_name.str);
|
|
break;
|
|
case INVALID_DEVICE_TYPE:
|
|
LogErr(WARNING_LEVEL, ER_ENGINE_COST_INVALID_DEVICE_TYPE_FOR_SE,
|
|
storage_category, se_name.str, cost_name.str);
|
|
break;
|
|
case INVALID_COST_VALUE:
|
|
LogErr(WARNING_LEVEL,
|
|
ER_ENGINE_COST_INVALID_CONST_CONSTANT_FOR_SE_AND_DEVICE,
|
|
cost_name.str, se_name.str, storage_category, value);
|
|
break;
|
|
default:
|
|
DBUG_ASSERT(false); /* purecov: inspected */
|
|
}
|
|
}
|
|
|
|
/**
|
|
Read the table that contains the cost constants for the server.
|
|
|
|
The table must already be opened. The cost constant object is updated
|
|
with cost constants found in the configuration table.
|
|
|
|
@param thd the THD
|
|
@param table the table to read from
|
|
@param [in,out] cost_constants cost constant object
|
|
*/
|
|
|
|
static void read_server_cost_constants(THD *thd, TABLE *table,
|
|
Cost_model_constants *cost_constants) {
|
|
DBUG_TRACE;
|
|
|
|
/*
|
|
The server constant table has the following columns:
|
|
|
|
cost_name VARCHAR(64) NOT NULL COLLATE utf8_general_ci
|
|
cost_value FLOAT DEFAULT NULL
|
|
last_update TIMESTAMP
|
|
comment VARCHAR(1024) DEFAULT NULL
|
|
*/
|
|
|
|
// Prepare to read from the table
|
|
unique_ptr_destroy_only<RowIterator> iterator =
|
|
init_table_iterator(thd, table, NULL, false,
|
|
/*ignore_not_found_rows=*/false);
|
|
if (iterator != nullptr) {
|
|
table->use_all_columns();
|
|
|
|
// Read one record
|
|
while (!iterator->Read()) {
|
|
/*
|
|
Check if a non-default value has been configured for this cost
|
|
constant.
|
|
*/
|
|
if (!table->field[1]->is_null()) {
|
|
char cost_name_buf[MAX_FIELD_WIDTH];
|
|
String cost_name(cost_name_buf, sizeof(cost_name_buf),
|
|
&my_charset_utf8_general_ci);
|
|
|
|
// Read the name of the cost constant
|
|
table->field[0]->val_str(&cost_name);
|
|
cost_name[cost_name.length()] = 0; // Null-terminate
|
|
|
|
// Read the value this cost constant should have
|
|
const float value = static_cast<float>(table->field[1]->val_real());
|
|
|
|
// Update the cost model with this cost constant
|
|
const LEX_CSTRING cost_constant = cost_name.lex_cstring();
|
|
const cost_constant_error err =
|
|
cost_constants->update_server_cost_constant(cost_constant, value);
|
|
|
|
if (err != COST_CONSTANT_OK)
|
|
report_server_cost_warnings(cost_constant, value, err);
|
|
}
|
|
}
|
|
} else {
|
|
LogErr(WARNING_LEVEL, ER_SERVER_COST_FAILED_TO_READ);
|
|
}
|
|
}
|
|
|
|
/**
|
|
Read the table that contains the cost constants for the storage engines.
|
|
|
|
The table must already be opened. The cost constant object is updated
|
|
with cost constants found in the configuration table.
|
|
|
|
@param thd the THD
|
|
@param table the table to read from
|
|
@param [in,out] cost_constants cost constant object
|
|
*/
|
|
|
|
static void read_engine_cost_constants(THD *thd, TABLE *table,
|
|
Cost_model_constants *cost_constants) {
|
|
DBUG_TRACE;
|
|
|
|
/*
|
|
The engine constant table has the following columns:
|
|
|
|
engine_name VARCHAR(64) NOT NULL COLLATE utf8_general_ci,
|
|
device_type INTEGER NOT NULL,
|
|
cost_name VARCHAR(64) NOT NULL COLLATE utf8_general_ci,
|
|
cost_value FLOAT DEFAULT NULL,
|
|
last_update TIMESTAMP
|
|
comment VARCHAR(1024) DEFAULT NULL,
|
|
*/
|
|
|
|
// Prepare to read from the table
|
|
unique_ptr_destroy_only<RowIterator> iterator =
|
|
init_table_iterator(thd, table, NULL, false,
|
|
/*ignore_not_found_rows=*/false);
|
|
if (iterator != nullptr) {
|
|
table->use_all_columns();
|
|
|
|
// Read one record
|
|
while (!iterator->Read()) {
|
|
/*
|
|
Check if a non-default value has been configured for this cost
|
|
constant.
|
|
*/
|
|
if (!table->field[3]->is_null()) {
|
|
char engine_name_buf[MAX_FIELD_WIDTH];
|
|
String engine_name(engine_name_buf, sizeof(engine_name_buf),
|
|
&my_charset_utf8_general_ci);
|
|
char cost_name_buf[MAX_FIELD_WIDTH];
|
|
String cost_name(cost_name_buf, sizeof(cost_name_buf),
|
|
&my_charset_utf8_general_ci);
|
|
|
|
// Read the name of the storage engine
|
|
table->field[0]->val_str(&engine_name);
|
|
engine_name[engine_name.length()] = 0; // Null-terminate
|
|
|
|
// Read the device type
|
|
const int device_type = static_cast<int>(table->field[1]->val_int());
|
|
|
|
// Read the name of the cost constant
|
|
table->field[2]->val_str(&cost_name);
|
|
cost_name[cost_name.length()] = 0; // Null-terminate
|
|
|
|
// Read the value this cost constant should have
|
|
const float value = static_cast<float>(table->field[3]->val_real());
|
|
|
|
// Update the cost model with this cost constant
|
|
const LEX_CSTRING engine = engine_name.lex_cstring();
|
|
const LEX_CSTRING cost_constant = cost_name.lex_cstring();
|
|
const cost_constant_error err =
|
|
cost_constants->update_engine_cost_constant(
|
|
thd, engine, device_type, cost_constant, value);
|
|
if (err != COST_CONSTANT_OK)
|
|
report_engine_cost_warnings(engine, device_type, cost_constant, value,
|
|
err);
|
|
}
|
|
}
|
|
} else {
|
|
LogErr(WARNING_LEVEL, ER_ENGINE_COST_FAILED_TO_READ);
|
|
}
|
|
}
|
|
|
|
/**
|
|
Read the cost configuration tables and update the cost constant set.
|
|
|
|
The const constant set must be initialized with default values when
|
|
calling this function.
|
|
|
|
@param cost_constants set with cost constants
|
|
*/
|
|
|
|
static void read_cost_constants(Cost_model_constants *cost_constants) {
|
|
DBUG_TRACE;
|
|
|
|
/*
|
|
This function creates its own THD. If there exists a current THD this needs
|
|
to be restored at the end of this function. The reason the current THD
|
|
can not be used is that this might already have opened and closed tables
|
|
and thus opening new tables will fail.
|
|
*/
|
|
THD *orig_thd = current_thd;
|
|
|
|
// Create and initialize a new THD.
|
|
THD *thd = new THD;
|
|
DBUG_ASSERT(thd);
|
|
thd->thread_stack = pointer_cast<char *>(&thd);
|
|
thd->store_globals();
|
|
lex_start(thd);
|
|
|
|
TABLE_LIST tables[2] = {TABLE_LIST("mysql", "server_cost", TL_READ),
|
|
TABLE_LIST("mysql", "engine_cost", TL_READ)};
|
|
tables[0].next_global = tables[0].next_local =
|
|
tables[0].next_name_resolution_table = &tables[1];
|
|
|
|
if (!open_and_lock_tables(thd, tables, MYSQL_LOCK_IGNORE_TIMEOUT)) {
|
|
DBUG_ASSERT(tables[0].table != NULL);
|
|
DBUG_ASSERT(tables[1].table != NULL);
|
|
|
|
// Read the server constants table
|
|
read_server_cost_constants(thd, tables[0].table, cost_constants);
|
|
// Read the storage engine table
|
|
read_engine_cost_constants(thd, tables[1].table, cost_constants);
|
|
} else {
|
|
LogErr(WARNING_LEVEL, ER_FAILED_TO_OPEN_COST_CONSTANT_TABLES);
|
|
}
|
|
|
|
trans_commit_stmt(thd);
|
|
close_thread_tables(thd);
|
|
lex_end(thd->lex);
|
|
|
|
// Delete the locally created THD
|
|
delete thd;
|
|
|
|
// If the caller already had a THD, this must be restored
|
|
if (orig_thd) orig_thd->store_globals();
|
|
}
|
|
|
|
void init_optimizer_cost_module(bool enable_plugins) {
|
|
DBUG_ASSERT(cost_constant_cache == NULL);
|
|
cost_constant_cache = new Cost_constant_cache();
|
|
cost_constant_cache->init();
|
|
/*
|
|
Initialize max_key_length and max_key_part_length for internal temporary
|
|
table engines.
|
|
*/
|
|
if (enable_plugins) init_cache_tmp_engine_properties();
|
|
}
|
|
|
|
void delete_optimizer_cost_module() {
|
|
if (cost_constant_cache) {
|
|
cost_constant_cache->close();
|
|
delete cost_constant_cache;
|
|
cost_constant_cache = NULL;
|
|
}
|
|
}
|
|
|
|
void reload_optimizer_cost_constants() {
|
|
if (cost_constant_cache) cost_constant_cache->reload();
|
|
}
|
|
|