摘要:

追踪在单线程中耗时的处理

耗时追踪:

日志埋点追踪:

[2022-08-15 14:24:22.946166] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:6445236 grouth: 60720 diff: 0.109540 diff_prepare: 0.006627 diff_add: 0.000194 diff_find: 0.062772 diff_put: 0.047780 num_put: 121428
[2022-08-15 14:24:23.062771] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:6505956 grouth: 61260 diff: 0.116552 diff_prepare: 0.006984 diff_add: 0.000198 diff_find: 0.064848 diff_put: 0.049420 num_put: 124956
[2022-08-15 14:24:23.173366] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:6567216 grouth: 60836 diff: 0.110529 diff_prepare: 0.006725 diff_add: 0.000191 diff_find: 0.063479 diff_put: 0.048347 num_put: 122460
[2022-08-15 14:24:23.288320] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:6628052 grouth: 60940 diff: 0.114900 diff_prepare: 0.006720 diff_add: 0.000199 diff_find: 0.063843 diff_put: 0.048677 num_put: 122688
[2022-08-15 14:24:23.399512] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:6688992 grouth: 60704 diff: 0.111138 diff_prepare: 0.006547 diff_add: 0.000189 diff_find: 0.064133 diff_put: 0.049099 num_put: 121548
[2022-08-15 14:24:23.516295] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:6749696 grouth: 60680 diff: 0.116727 diff_prepare: 0.006679 diff_add: 0.000193 diff_find: 0.063542 diff_put: 0.048429 num_put: 122184
[2022-08-15 14:24:23.627377] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:6810376 grouth: 60720 diff: 0.111024 diff_prepare: 0.006844 diff_add: 0.000197 diff_find: 0.063667 diff_put: 0.048514 num_put: 122232
[2022-08-15 14:24:23.737050] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:6871096 grouth: 60652 diff: 0.109618 diff_prepare: 0.006515 diff_add: 0.000188 diff_find: 0.062811 diff_put: 0.047869 num_put: 120900
[2022-08-15 14:24:23.851360] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:6931748 grouth: 60716 diff: 0.114247 diff_prepare: 0.006859 diff_add: 0.000202 diff_find: 0.064801 diff_put: 0.049638 num_put: 122700
[2022-08-15 14:24:23.970047] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:6992464 grouth: 60856 diff: 0.118632 diff_prepare: 0.006724 diff_add: 0.000197 diff_find: 0.063345 diff_put: 0.048251 num_put: 121692
[2022-08-15 14:24:24.081066] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:7053320 grouth: 60960 diff: 0.110953 diff_prepare: 0.006540 diff_add: 0.000190 diff_find: 0.064054 diff_put: 0.048781 num_put: 124248
[2022-08-15 14:24:24.191382] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:7114280 grouth: 60904 diff: 0.110255 diff_prepare: 0.006611 diff_add: 0.000193 diff_find: 0.063375 diff_put: 0.048254 num_put: 122472
[2022-08-15 14:24:24.303733] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:7175184 grouth: 60936 diff: 0.112298 diff_prepare: 0.006960 diff_add: 0.000199 diff_find: 0.064662 diff_put: 0.049237 num_put: 124044
[2022-08-15 14:24:24.419913] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:7236120 grouth: 60700 diff: 0.116123 diff_prepare: 0.006719 diff_add: 0.000200 diff_find: 0.064567 diff_put: 0.048358 num_put: 122436
[2022-08-15 14:24:24.530680] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:7296820 grouth: 60980 diff: 0.110708 diff_prepare: 0.006647 diff_add: 0.000192 diff_find: 0.063673 diff_put: 0.048530 num_put: 123720
[2022-08-15 14:24:24.639276] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:7357800 grouth: 60708 diff: 0.108543 diff_prepare: 0.006652 diff_add: 0.000191 diff_find: 0.063180 diff_put: 0.048181 num_put: 121248
[2022-08-15 14:24:24.657156] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:7418508 grouth: 4276 diff: 0.017845 diff_prepare: 0.000535 diff_add: 0.000015 diff_find: 0.004489 diff_put: 0.003414 num_put: 8592
[2022-08-15 14:24:24.657175] [2412] [INFO] [aggregation_algorithm.cpp:302] MSG: MultiDimensionalGroupByScan foreach mit AggregatePackrow num: 123 diff: 13.436162
[2022-08-15 14:24:51.870654] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:425684 grouth: 60856 diff: 0.071273 diff_prepare: 0.007115 diff_add: 0.000298 diff_find: 0.021371 diff_put: 0.015455 num_put: 33432
[2022-08-15 14:24:51.987617] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:486540 grouth: 60752 diff: 0.116824 diff_prepare: 0.018261 diff_add: 0.000808 diff_find: 0.053993 diff_put: 0.038006 num_put: 93348
[2022-08-15 14:24:52.108107] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:547292 grouth: 60676 diff: 0.120426 diff_prepare: 0.018962 diff_add: 0.000782 diff_find: 0.053169 diff_put: 0.037344 num_put: 94020
[2022-08-15 14:24:52.225674] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:607968 grouth: 60712 diff: 0.117505 diff_prepare: 0.019740 diff_add: 0.000772 diff_find: 0.053401 diff_put: 0.037652 num_put: 94140
[2022-08-15 14:24:52.343361] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:668680 grouth: 60996 diff: 0.117613 diff_prepare: 0.015985 diff_add: 0.000579 diff_find: 0.051666 diff_put: 0.037636 num_put: 93636
[2022-08-15 14:24:52.439007] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:729676 grouth: 61012 diff: 0.095548 diff_prepare: 0.007104 diff_add: 0.000193 diff_find: 0.048993 diff_put: 0.037360 num_put: 93468
[2022-08-15 14:24:52.532357] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:790688 grouth: 61016 diff: 0.093281 diff_prepare: 0.006180 diff_add: 0.000182 diff_find: 0.047905 diff_put: 0.036392 num_put: 92784
[2022-08-15 14:24:52.628666] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:851704 grouth: 60832 diff: 0.096247 diff_prepare: 0.006229 diff_add: 0.000183 diff_find: 0.048750 diff_put: 0.037058 num_put: 94320
[2022-08-15 14:24:52.730149] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:912536 grouth: 60788 diff: 0.101424 diff_prepare: 0.006093 diff_add: 0.000178 diff_find: 0.048274 diff_put: 0.036737 num_put: 93528
[2022-08-15 14:24:52.824944] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:973324 grouth: 60796 diff: 0.094695 diff_prepare: 0.006528 diff_add: 0.000192 diff_find: 0.048764 diff_put: 0.037093 num_put: 94248
[2022-08-15 14:24:52.919658] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:1034120 grouth: 60836 diff: 0.094649 diff_prepare: 0.006288 diff_add: 0.000186 diff_find: 0.048135 diff_put: 0.036662 num_put: 92748
[2022-08-15 14:24:53.013901] [2412] [INFO] [aggregation_algorithm.cpp:655] MSG: AggregatePackrow foreach mit cur:1094956 grouth: 60896 diff: 0.094170 diff_prepare: 0.006317 diff_add: 0.000187 diff_find: 0.048477 diff_put: 0.036937 num_put: 93480

调用堆栈:

(gdb) bt
#0  Tianmu::core::ColumnBinEncoder::EncoderText_UTF::Encode (this=0x7fb0dc91cd60, buf=0x7fb0dc91ba00 "", buf_sec=0x7fb0dc91ba4b "", vc=0x7fb0dca9e130, mit=..., update_stats=false)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/column_bin_encoder.cpp:944
#1  0x0000000003023c01 in Tianmu::core::ColumnBinEncoder::Encode (this=0x7fb0dc006840, buf=0x7fb0dc91ba00 "", mit=..., alternative_vc=0x0, update_stats=false)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/column_bin_encoder.cpp:169
#2  0x000000000300a737 in Tianmu::core::GroupTable::PutGroupingValue (this=0x7fd409ddd2e8, col=0, mit=...)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/group_table.h:85
#3  0x000000000300aaa5 in Tianmu::core::GroupByWrapper::PutGroupingValue (this=0x7fd409ddd220, gr_a=0, mit=...)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/groupby_wrapper.h:82
#4  0x00000000030073ec in Tianmu::core::AggregationAlgorithm::AggregatePackrow (this=0x7fd409ddd580, gbw=..., mit=0x7fd409ddced0, cur_tuple=0)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/aggregation_algorithm.cpp:575
#5  0x0000000003005b94 in Tianmu::core::AggregationAlgorithm::MultiDimensionalGroupByScan (this=0x7fd409ddd580, gbw=..., limit=@0x7fd409ddd208: 7422784, offset=@0x7fd409ddd608: 0, sender=0x0, 
    limit_less_than_no_groups=false) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/aggregation_algorithm.cpp:284
#6  0x00000000030053ca in Tianmu::core::AggregationAlgorithm::Aggregate (this=0x7fd409ddd580, just_distinct=false, limit=@0x7fd409ddd600: -1, offset=@0x7fd409ddd608: 0, sender=0x0)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/aggregation_algorithm.cpp:196
#7  0x0000000002df1e3e in Tianmu::core::TempTable::Materialize (this=0x7fb0dc0013d0, in_subq=false, sender=0x7fb0dc931ed0, lazy=false)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/temp_table.cpp:1972
#8  0x0000000002d3a414 in Tianmu::core::Engine::Execute (this=0x8850d60, thd=0x7fb0dc0125f0, lex=0x7fb0dc014918, result_output=0x7fb0dcac60a0, unit_for_union=0x0)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/engine_execute.cpp:426
#9  0x0000000002d395b6 in Tianmu::core::Engine::HandleSelect (this=0x8850d60, thd=0x7fb0dc0125f0, lex=0x7fb0dc014918, result=@0x7fd409dddd18: 0x7fb0dcac60a0, setup_tables_done_option=0, 
    res=@0x7fd409dddd14: 0, optimize_after_tianmu=@0x7fd409dddd0c: 1, tianmu_free_join=@0x7fd409dddd10: 1, with_insert=0)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/engine_execute.cpp:232
#10 0x0000000002e21e47 in Tianmu::dbhandler::TIANMU_HandleSelect (thd=0x7fb0dc0125f0, lex=0x7fb0dc014918, result=@0x7fd409dddd18: 0x7fb0dcac60a0, setup_tables_done_option=0, res=@0x7fd409dddd14: 0, 
    optimize_after_tianmu=@0x7fd409dddd0c: 1, tianmu_free_join=@0x7fd409dddd10: 1, with_insert=0)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/handler/ha_rcengine.cpp:82
#11 0x0000000002462f6a in execute_sqlcom_select (thd=0x7fb0dc0125f0, all_tables=0x7fb0dcb67548) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/sql/sql_parse.cc:5182
#12 0x000000000245c2ee in mysql_execute_command (thd=0x7fb0dc0125f0, first_level=true) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/sql/sql_parse.cc:2831
#13 0x0000000002463f33 in mysql_parse (thd=0x7fb0dc0125f0, parser_state=0x7fd409ddeeb0) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/sql/sql_parse.cc:5621
#14 0x00000000024591cb in dispatch_command (thd=0x7fb0dc0125f0, com_data=0x7fd409ddf650, command=COM_QUERY) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/sql/sql_parse.cc:1495
#15 0x00000000024580f7 in do_command (thd=0x7fb0dc0125f0) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/sql/sql_parse.cc:1034
#16 0x000000000258accd in handle_connection (arg=0xc04bf80) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/sql/conn_handler/connection_handler_per_thread.cc:313
#17 0x0000000002c71102 in pfs_spawn_thread (arg=0x16593df0) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/perfschema/pfs.cc:2197
#18 0x00007fd458e22ea5 in start_thread () from /lib64/libpthread.so.0
#19 0x00007fd457057b0d in clone () from /lib64/libc.so.6

(gdb) bt
#0  my_strnxfrm_unicode (cs=0x487ec20 , dst=0x7f98f4ba5970 "", dstlen=16, nweights=16, 
    src=0x7f98ffec0000 "Brand#13Brand#13Brand#42Brand#34Brand#32Brand#24Brand#11Brand#44Brand#43Brand#54Brand#25Brand#33Brand#55Brand#13Brand#15Brand#32Brand#43Brand#11Brand#23Brand#12Brand#33Brand#43Brand#35Brand#52Brand#55"..., srclen=8, flags=64) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/strings/ctype-utf8.c:5146
#1  0x00000000030035e9 in Tianmu::common::strnxfrm (collation=..., src=0x7f98f4ba5970 "", src_len=16, 
    dest=0x7f98ffec0000 "Brand#13Brand#13Brand#42Brand#34Brand#32Brand#24Brand#11Brand#44Brand#43Brand#54Brand#25Brand#33Brand#55Brand#13Brand#15Brand#32Brand#43Brand#11Brand#23Brand#12Brand#33Brand#43Brand#35Brand#52Brand#55"..., dest_len=8) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/common/mysql_gate.cpp:45
#2  0x00000000030278e7 in Tianmu::core::ColumnBinEncoder::EncoderText_UTF::Encode (this=0x7f98f4919ea0, buf=0x7f98f4ba5970 "", buf_sec=0x7f98f4ba59bb "", vc=0x7f98f4a38a80, mit=..., 
    update_stats=false) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/column_bin_encoder.cpp:941
#3  0x0000000003023c9f in Tianmu::core::ColumnBinEncoder::Encode (this=0x7f98f4988e80, buf=0x7f98f4ba5970 "", mit=..., alternative_vc=0x0, update_stats=false)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/column_bin_encoder.cpp:169
#4  0x000000000300a7d5 in Tianmu::core::GroupTable::PutGroupingValue (this=0x7fbc212ae2e8, col=0, mit=...)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/group_table.h:85
#5  0x000000000300ab43 in Tianmu::core::GroupByWrapper::PutGroupingValue (this=0x7fbc212ae220, gr_a=0, mit=...)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/groupby_wrapper.h:82
#6  0x00000000030073fc in Tianmu::core::AggregationAlgorithm::AggregatePackrow (this=0x7fbc212ae580, gbw=..., mit=0x7fbc212aded0, cur_tuple=0)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/aggregation_algorithm.cpp:577
#7  0x0000000003005b94 in Tianmu::core::AggregationAlgorithm::MultiDimensionalGroupByScan (this=0x7fbc212ae580, gbw=..., limit=@0x7fbc212ae208: 7422784, offset=@0x7fbc212ae608: 0, sender=0x0, 
    limit_less_than_no_groups=false) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/aggregation_algorithm.cpp:284
#8  0x00000000030053ca in Tianmu::core::AggregationAlgorithm::Aggregate (this=0x7fbc212ae580, just_distinct=false, limit=@0x7fbc212ae600: -1, offset=@0x7fbc212ae608: 0, sender=0x0)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/aggregation_algorithm.cpp:196
#9  0x0000000002df1e3e in Tianmu::core::TempTable::Materialize (this=0x7f98f4b9e1d0, in_subq=false, sender=0x7f98f4931ed0, lazy=false)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/temp_table.cpp:1972
#10 0x0000000002d3a414 in Tianmu::core::Engine::Execute (this=0x8568190, thd=0x7f98f40125f0, lex=0x7f98f4014918, result_output=0x7f98f4b90fa0, unit_for_union=0x0)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/engine_execute.cpp:426
#11 0x0000000002d395b6 in Tianmu::core::Engine::HandleSelect (this=0x8568190, thd=0x7f98f40125f0, lex=0x7f98f4014918, result=@0x7fbc212aed18: 0x7f98f4b90fa0, setup_tables_done_option=0, 
    res=@0x7fbc212aed14: 0, optimize_after_tianmu=@0x7fbc212aed0c: 1, tianmu_free_join=@0x7fbc212aed10: 1, with_insert=0)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/core/engine_execute.cpp:232
#12 0x0000000002e21e47 in Tianmu::dbhandler::TIANMU_HandleSelect (thd=0x7f98f40125f0, lex=0x7f98f4014918, result=@0x7fbc212aed18: 0x7f98f4b90fa0, setup_tables_done_option=0, res=@0x7fbc212aed14: 0, 
    optimize_after_tianmu=@0x7fbc212aed0c: 1, tianmu_free_join=@0x7fbc212aed10: 1, with_insert=0)
    at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/tianmu/handler/ha_rcengine.cpp:82
#13 0x0000000002462f6a in execute_sqlcom_select (thd=0x7f98f40125f0, all_tables=0x7f98f4b674e8) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/sql/sql_parse.cc:5182
#14 0x000000000245c2ee in mysql_execute_command (thd=0x7f98f40125f0, first_level=true) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/sql/sql_parse.cc:2831
#15 0x0000000002463f33 in mysql_parse (thd=0x7f98f40125f0, parser_state=0x7fbc212afeb0) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/sql/sql_parse.cc:5621
#16 0x00000000024591cb in dispatch_command (thd=0x7f98f40125f0, com_data=0x7fbc212b0650, command=COM_QUERY) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/sql/sql_parse.cc:1495
#17 0x00000000024580f7 in do_command (thd=0x7f98f40125f0) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/sql/sql_parse.cc:1034
#18 0x000000000258accd in handle_connection (arg=0xb4d1ed0) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/sql/conn_handler/connection_handler_per_thread.cc:313
#19 0x0000000002c71102 in pfs_spawn_thread (arg=0x16229df0) at /home/jenkins/workspace/stonedb5.7-zsl-centos7.9-30-119-20220805/storage/perfschema/pfs.cc:2197
#20 0x00007fbc70ae1ea5 in start_thread () from /lib64/libpthread.so.0
#21 0x00007fbc6ed16b0d in clone () from /lib64/libc.so.6

核心函数：

ColumnBinEncoder::EncoderText_UTF::Encode

void ColumnBinEncoder::EncoderText_UTF::Encode(uchar *buf, uchar *buf_sec, vcolumn::VirtualColumn *vc, MIIterator &mit,
                                               bool update_stats) {
  if (null_status > 0 && vc->IsNull(mit)) {
    SetNull(buf, buf_sec);
    return;
  }
  std::memset(buf, 0, size);
  types::BString s;
  vc->GetNotNullValueString(s, mit);
  if (update_stats) {
    if (!min_max_set) {
      maxs.PersistentCopy(s);
      mins.PersistentCopy(s);
      min_max_set = true;
    } else {
      if (CollationStrCmp(collation, s, maxs) > 0) maxs.PersistentCopy(s);
      if (CollationStrCmp(collation, s, mins) < 0) mins.PersistentCopy(s);
    }
  }
  common::strnxfrm(collation, buf, size - sizeof(uint32_t), (uchar *)s.GetDataBytesPointer(), s.len);
  // int coded_len = types::CollationBufLen(collation, s.len);
  uint32_t length = s.len + 1;
  std::memcpy(buf + size - sizeof(uint32_t), &length, sizeof(uint32_t));
  if (descending) Negate(buf, size);
  if (size_sec > 0) {
    std::memset(buf_sec, 0, size_sec);
    std::memcpy(buf_sec + size_sec - sizeof(uint32_t), &length, sizeof(uint32_t));
    if (s.len > 0) std::memcpy(buf_sec, s.GetDataBytesPointer(), s.len);
  }
}

该函数原始实现:

bool ColumnBinEncoder::EncoderText_UTF::Encode(uchar* buf, uchar* buf_sec, RCBString& s, bool sec_column, bool update_stats)
{
	if(null_status > 0 && s.IsNull()) {
		SetNull(buf, buf_sec);
		return true;
	}
	memset(buf, 0, size);
	if(update_stats) {
		if(!min_max_set) {
			maxs = s;
			mins = s;
			min_max_set = true;
		} else {
			if(CollationStrCmp(collation, s, maxs) > 0)
				maxs = s;
			if(CollationStrCmp(collation, s, mins) < 0)
				mins = s;
		}
	}
	strnxfrm(collation, buf, size - 2, (uchar*)s.Value(), s.len);
	//int coded_len = CollationBufLen(collation, s.len);
	buf[size - 2] = (size - 2 + 1) / 256;
	buf[size - 1] = (size - 2 + 1) % 256;
	if(descending)
		Negate(buf, size);
	if(size_sec > 0) {
		memset(buf_sec, 0, size_sec);
		buf_sec[size_sec - 2] = (s.len + 1) / 256;
		buf_sec[size_sec - 1] = (s.len + 1) % 256;
		if(s.len > 0)
			memcpy(buf_sec, s.GetDataBytesPointer(), s.len);
	}
	return true;
}

耗时原因分析：

一. like string 的子条件被判定为需要走聚合

void GroupByWrapper::AddAggregatedColumn(int orig_attr_no, TempTable::Attr &a, int64_t max_no_vals, int64_t min_v,
                                         int64_t max_v, int max_size)

{
  // MEASURE_FET("GroupByWrapper::AddAggregatedColumn(...)");
  GT_Aggregation ag_oper;
  common::CT ag_type = a.TypeName();  // original type, not the output one (it
                                      // is important e.g. for AVG)
  int ag_size = max_size;
  int ag_prec = a.Type().GetScale();
  bool ag_distinct = a.distinct;
  int attr_no = no_attr;  // i.e. add at the end (after all grouping cols and
                          // previous aggr.cols)
  DTCollation ag_collation = a.GetCollation();

  virt_col[attr_no] = a.term.vc;

  DEBUG_ASSERT(virt_col[attr_no] || a.term.IsNull());  // the second possibility is count(*)

  is_lookup[attr_no] = false;
  dist_vals[attr_no] = max_no_vals;

  switch (a.mode) {
    case common::ColOperation::SUM:
      ag_oper = GT_Aggregation::GT_SUM;
      ag_type = virt_col[attr_no]->TypeName();
      ag_prec = virt_col[attr_no]->Type().GetScale();
      break;
    case common::ColOperation::AVG:
      ag_oper = GT_Aggregation::GT_AVG;
      ag_type = virt_col[attr_no]->TypeName();
      ag_prec = virt_col[attr_no]->Type().GetScale();
      break;
    case common::ColOperation::MIN:
      ag_oper = GT_Aggregation::GT_MIN;
      break;
    case common::ColOperation::MAX:
      ag_oper = GT_Aggregation::GT_MAX;
      break;
    case common::ColOperation::COUNT:
      if (a.term.IsNull() || (!ag_distinct && virt_col[attr_no]->IsConst())) {
        if (virt_col[attr_no] && virt_col[attr_no]->IsConst()) {
          MIIterator dummy(NULL, p_power);
          if (virt_col[attr_no]->IsNull(dummy)) {
            ag_oper = GT_Aggregation::GT_COUNT_NOT_NULL;
            ag_type = virt_col[attr_no]->TypeName();
            ag_size = max_size;
          } else {
            virt_col[attr_no] = NULL;  // forget about constant in count(...), except null
            ag_oper = GT_Aggregation::GT_COUNT;
          }
        } else {
          virt_col[attr_no] = NULL;  // forget about constant in count(...), except null
          ag_oper = GT_Aggregation::GT_COUNT;
        }
      } else {
        ag_oper = GT_Aggregation::GT_COUNT_NOT_NULL;
        ag_type = virt_col[attr_no]->TypeName();
        ag_size = max_size;
      }
      break;
    case common::ColOperation::LISTING:
      ag_oper = GT_Aggregation::GT_LIST;
      break;
    case common::ColOperation::VAR_POP:
      ag_oper = GT_Aggregation::GT_VAR_POP;
      ag_type = virt_col[attr_no]->TypeName();
      ag_prec = virt_col[attr_no]->Type().GetScale();
      break;
    case common::ColOperation::VAR_SAMP:
      ag_oper = GT_Aggregation::GT_VAR_SAMP;
      ag_type = virt_col[attr_no]->TypeName();
      ag_prec = virt_col[attr_no]->Type().GetScale();
      break;
    case common::ColOperation::STD_POP:
      ag_oper = GT_Aggregation::GT_STD_POP;
      ag_type = virt_col[attr_no]->TypeName();
      ag_prec = virt_col[attr_no]->Type().GetScale();
      break;
    case common::ColOperation::STD_SAMP:
      ag_oper = GT_Aggregation::GT_STD_SAMP;
      ag_type = virt_col[attr_no]->TypeName();
      ag_prec = virt_col[attr_no]->Type().GetScale();
      break;
    case common::ColOperation::BIT_AND:
      ag_oper = GT_Aggregation::GT_BIT_AND;
      break;
    case common::ColOperation::BIT_OR:
      ag_oper = GT_Aggregation::GT_BIT_OR;
      break;
    case common::ColOperation::BIT_XOR:
      ag_oper = GT_Aggregation::GT_BIT_XOR;
      break;
    case common::ColOperation::GROUP_CONCAT:
      ag_oper = GT_Aggregation::GT_GROUP_CONCAT;
      break;
    default:
      throw common::NotImplementedException("Aggregation not implemented");
  }

  if (virt_col[attr_no] && virt_col[attr_no]->Type().IsLookup() &&
      !types::RequiresUTFConversions(virt_col[attr_no]->GetCollation()) &&
      (ag_oper == GT_Aggregation::GT_COUNT || ag_oper == GT_Aggregation::GT_COUNT_NOT_NULL ||
       ag_oper == GT_Aggregation::GT_LIST)) {
    // lookup for these operations may use codes
    ag_size = 4;  // integer
    ag_prec = 0;
    ag_type = common::CT::INT;
    is_lookup[attr_no] = true;
  }
  if (ag_oper == GT_Aggregation::GT_COUNT)
    input_mode[attr_no] = GBInputMode::GBIMODE_NO_VALUE;
  else if (ag_oper == GT_Aggregation::GT_GROUP_CONCAT)
    input_mode[attr_no] = GBInputMode::GBIMODE_AS_TEXT;
  else
    input_mode[attr_no] =
        (ATI::IsStringType(virt_col[attr_no]->TypeName()) &&
                 (!is_lookup[attr_no] || types::RequiresUTFConversions(virt_col[attr_no]->GetCollation()))
             ? GBInputMode::GBIMODE_AS_TEXT
             : GBInputMode::GBIMODE_AS_INT64);

  TIANMU_LOG(LogCtl_Level::DEBUG,
              "attr_no %d, input_mode[attr_no] %d, a.alias %s, a.si.separator "
              "%s, direction %d, ag_type %d, ag_size %d",
              attr_no, input_mode[attr_no], a.alias, a.si.separator.c_str(), a.si.order, ag_type, ag_size);

  gt.AddAggregatedColumn(virt_col[attr_no], ag_oper, ag_distinct, ag_type, ag_size, ag_prec, ag_collation,
                         a.si);  // note: size will be automatically calculated for all numericals
  gt.AggregatedColumnStatistics(no_aggregated_attr, max_no_vals, min_v, max_v);
  attr_mapping[orig_attr_no] = attr_no;
  no_aggregated_attr++;
  no_attr++;
}

    case common::ColOperation::LISTING:
      ag_oper = GT_Aggregation::GT_LIST;
      break;

二. 聚合时将string类型的值都做了一次memcpy

void ColumnBinEncoder::EncoderText_UTF::Encode(uchar *buf, uchar *buf_sec, vcolumn::VirtualColumn *vc, MIIterator &mit,
                                               bool update_stats) {
  if (null_status > 0 && vc->IsNull(mit)) {
    SetNull(buf, buf_sec);
    return;
  }
  std::memset(buf, 0, size);
  types::BString s;
  vc->GetNotNullValueString(s, mit);
  if (update_stats) {
    if (!min_max_set) {
      maxs.PersistentCopy(s);
      mins.PersistentCopy(s);
      min_max_set = true;
    } else {
      if (CollationStrCmp(collation, s, maxs) > 0) maxs.PersistentCopy(s);
      if (CollationStrCmp(collation, s, mins) < 0) mins.PersistentCopy(s);
    }
  }
  common::strnxfrm(collation, buf, size - sizeof(uint32_t), (uchar *)s.GetDataBytesPointer(), s.len);
  // int coded_len = types::CollationBufLen(collation, s.len);
  uint32_t length = s.len + 1;
  std::memcpy(buf + size - sizeof(uint32_t), &length, sizeof(uint32_t));
  if (descending) Negate(buf, size);
  if (size_sec > 0) {
    std::memset(buf_sec, 0, size_sec);
    std::memcpy(buf_sec + size_sec - sizeof(uint32_t), &length, sizeof(uint32_t));
    if (s.len > 0) std::memcpy(buf_sec, s.GetDataBytesPointer(), s.len);
  }
}

bool ValueMatching_LookupTable::FindCurrentRow(unsigned char *input_buffer, int64_t &row, bool add_if_new) {
  row = 0;
  std::memcpy(&row, input_buffer, matching_width);
  DEBUG_ASSERT(row < max_no_rows);
  if (occupied->Get(row)) return true;
  if (!add_if_new) {
    row = common::NULL_VALUE_64;
    return false;
  }
  std::memcpy(t + row * total_width, input_buffer, input_buffer_width);
  occupied->Set(row);
  occupied_table[no_rows] = (int)row;
  no_rows++;
  return false;
}