Details
-
Bug
-
Status: Open (View Workflow)
-
Minor
-
Resolution: Unresolved
-
10.1(EOL)
-
None
-
None
Description
Data comes from Sandy Bridge system running sysbench OLTP RO in 1 thread against 1 table.
Call graphs:
- 0.15% mysqld mysqld
|
- Item::cmp_type() const
|
+ 37.20% Item_func::fix_fields(THD*, Item**)
|
+ 13.65% Item_func::setup_args_and_comparator(THD*, Arg_comparator*)
|
+ 10.08% Item_equal::add_const(Item*, Item*)
|
+ 5.16% Item_equal::fix_fields(THD*, Item**)
|
+ 4.68% build_equal_items_for_cond(THD*, Item*, COND_EQUAL*, bool)
|
+ 4.36% update_ref_and_keys(THD*, st_dynamic_array*, st_join_table*, unsigned int, Item*, unsigned long long, st_select_lex*, st_sargable_param**) [clone .isra.253]
|
+ 4.14% get_mm_parts(RANGE_OPT_PARAM*, Item*, Field*, Item_func::Functype, Item*, Item_result) [clone .isra.162] [clone .part.163]
|
+ 3.54% Item_func_between::fix_length_and_dec()
|
+ 2.94% check_simple_equality(Item*, Item*, Item*, COND_EQUAL*)
|
+ 2.69% Item::cache_const_expr_transformer(unsigned char*)
|
+ 2.13% Item_bool_func2::set_cmp_func()
|
+ 1.94% Arg_comparator::set_cmp_func(Item_result_field*, Item**, Item**, bool)
|
+ 1.63% Field::can_optimize_keypart_ref(Item_func const*, Item const*) const
|
+ 1.27% Item::charset_for_protocol() const
|
+ 1.11% Item_equal::fix_length_and_dec()
|
+ 0.95% Item::init_make_field(Send_field*, enum_field_types)
|
+ 0.80% Protocol::send_result_set_metadata(List<Item>*, unsigned int)
|
+ 0.79% Item_equal::Item_equal(Item*, Item*, bool)
|
+ 0.63% get_mm_leaf(RANGE_OPT_PARAM*, Item*, Field*, st_key_part*, Item_func::Functype, Item*)
|
This is virtual method which can't be inlined. Most time spent for function call convention. Check if we can revoke it's virtual status.
In this script:
DROP TABLE IF EXISTS t1;CREATE TABLE t1 (id INTEGER UNSIGNED NOT NULL AUTO_INCREMENT,k INTEGER UNSIGNED DEFAULT '0' NOT NULL,c CHAR(120) DEFAULT '' NOT NULL,pad CHAR(60) DEFAULT '' NOT NULL,PRIMARY KEY (id)) ENGINE=MyISAM;INSERT INTO t1 (k, c, pad) VALUES (10, 'a', 'xxx');INSERT INTO t1 (k, c, pad) VALUES (11, 'a', 'xxx');INSERT INTO t1 (k, c, pad) VALUES (12, 'a', 'xxx');INSERT INTO t1 (k, c, pad) VALUES (13, 'a', 'xxx');INSERT INTO t1 (k, c, pad) VALUES (14, 'a', 'xxx');INSERT INTO t1 (k, c, pad) VALUES (15, 'a', 'xxx');INSERT INTO t1 (k, c, pad) VALUES (16, 'a', 'xxx');SELECT * FROM t1 WHERE id=13;the last SELECT query generates the following Item::cmp_type() calls (7 calls total):
#1 0x0000555555c788a8 in Item_func::setup_args_and_comparator (#2 0x0000555555c78a9b in Item_bool_func2::fix_length_and_dec (#3 0x0000555555ca5e38 in Item_func::fix_fields (this=0x7fff500014a8,...#1 0x0000555555a911dd in Arg_comparator::set_cmp_func (this=0x7fff50001570,#2 0x0000555555c78a23 in Item_func::setup_args_and_comparator (#3 0x0000555555c78a9b in Item_bool_func2::fix_length_and_dec (#4 0x0000555555ca5e38 in Item_func::fix_fields (this=0x7fff500014a8,...#1 0x0000555555a911fc in Arg_comparator::set_cmp_func (this=0x7fff50001570,#2 0x0000555555c78a23 in Item_func::setup_args_and_comparator (#3 0x0000555555c78a9b in Item_bool_func2::fix_length_and_dec (#4 0x0000555555ca5e38 in Item_func::fix_fields (this=0x7fff500014a8,...#1 0x0000555555a6ef54 in check_simple_equality (thd=0x55555a932650,#2 0x0000555555a6f495 in Item_func_eq::check_equality (this=0x7fff500014a8,#3 0x0000555555a6fa77 in Item_func_eq::build_equal_items (#4 0x0000555555a700e3 in build_equal_items (join=0x7fff50001708,#5 0x0000555555a737af in optimize_cond (join=0x7fff50001708,...#1 0x0000555555c89292 in Item_equal::Item_equal (this=0x7fff50002228,#2 0x0000555555a6f18e in check_simple_equality (thd=0x55555a932650,#3 0x0000555555a6f495 in Item_func_eq::check_equality (this=0x7fff500014a8,#4 0x0000555555a6fa77 in Item_func_eq::build_equal_items (#5 0x0000555555a700e3 in build_equal_items (join=0x7fff50001708,#6 0x0000555555a737af in optimize_cond (join=0x7fff50001708,...#1 0x0000555555c8a114 in Item_equal::fix_length_and_dec (this=0x7fff50002228)#2 0x0000555555c89d79 in Item_equal::fix_fields (this=0x7fff50002228,#3 0x0000555555a6fb38 in Item_func_eq::build_equal_items (#4 0x0000555555a700e3 in build_equal_items (join=0x7fff50001708,#5 0x0000555555a737af in optimize_cond (join=0x7fff50001708,...#1 0x0000555555c15e98 in Field::can_optimize_keypart_ref (#2 0x0000555555a5c649 in add_key_part (keyuse_array=0x7fff50001a10,#3 0x0000555555a5d6bb in update_ref_and_keys (thd=0x55555a932650,#4 0x0000555555a585e6 in make_join_statistics (join=0x7fff50001708,#5 0x0000555555a505fc in JOIN::optimize_inner (this=0x7fff50001708)#6 0x0000555555a4f590 in JOIN::optimize (this=0x7fff50001708)5 out of 7 calls are done by Item_field
2 out of 7 calls are done by Item_int