1
我有一个应用程序对数据库的更新操作而非（更典型的）SELECT检索非常重要。只是猜测，但每个SELECT可能有100个更新。重型更新应用程序中的MySQL性能调优
使用的MySQL服务器是5.6.31-0ubuntu0.14.04.2-log。我已经做了很多服务器的性能，包括设置选项，如调谐的：
innodb_change_buffer_max_size=50
（文档上innodb_change_buffer_max_size是HERE我将在这篇文章的末尾发布的所有服务器变量。）
我遇到的问题是服务器性能中的周期性“打嗝”，导致SQL查询的小群集延迟几秒钟。例如，查询序列通常在毫秒内完成，在“打嗝”期间，每个查询将花费3-110秒。 （是的，有时几乎延迟了两分钟）
虽然延迟群集中有许多不同的SQL查询，但群集中的几乎所有这些查询都使用MySQL'INSERT ... ON DUPLICATE KEY UPDATE'语句类型。例如：
INSERT INTO `PerfCounters` SET `PerfID`='scriptname',`PID`=27802
ON DUPLICATE KEY UPDATE `ThisHour`=`ThisHour`+1;
这个特定示例中的表结构是：
CREATE TABLE IF NOT EXISTS `PerfCounters` (
`PerfID` varchar(30) NOT NULL,
`PID` int(11) NOT NULL DEFAULT '0',
`ThisHour` int(11) NOT NULL DEFAULT '1',
PRIMARY KEY (`PerfID`,`PID`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
我越来越相信，“打嗝”表明，MySQL是非常繁忙做某种行政或维护功能必须先完成，然后才能继续处理其他挂起的查询。但是，我并不确定。
下面是从慢查询日志中的条目上面的例子：
# [email protected]: demouser[demouser] @ mysql.myhost.com [0.0.0.0] Id: 453134
# Query_time: 2.822141 Lock_time: 0.000096 Rows_sent: 0 Rows_examined: 0
SET timestamp=1473074105;
INSERT INTO `PerfCounters` SET `PerfID`='scriptname',`PID`=27802 ON DUPLICATE KEY UPDATE `ThisHour`=`ThisHour`+1;
正如你所看到的，延迟不因行锁或其他锁定争用问题。实际上，由于'PID'（进程ID）是组合键的一部分，并且没有两个并发任务可以具有相同的PID，因此100％保证永远不会有行锁。
有没有人对性能调整这个具体情况有什么建议？是否有特定的服务器变量设置可以提高重新更新应用程序的性能？
也许更重要的一点是：延迟“打嗝”是否表明MySQL正在忙于某种高优先级的管理或维护操作？
服务器变量
auto_increment_increment=1
auto_increment_offset=1
autocommit=ON
automatic_sp_privileges=ON
avoid_temporal_upgrade=OFF
back_log=90
basedir=/usr
big_tables=OFF
bind_address=mysql.myhost.com
binlog_cache_size=32,768
binlog_checksum=CRC32
binlog_direct_non_transactional_updates=OFF
binlog_error_action=IGNORE_ERROR
binlog_format=STATEMENT
binlog_gtid_simple_recovery=OFF
binlog_max_flush_queue_time=0
binlog_order_commits=ON
binlog_row_image=FULL
binlog_rows_query_log_events=OFF
binlog_stmt_cache_size=32,768
binlogging_impossible_mode=IGNORE_ERROR
block_encryption_mode=aes-128-ecb
bulk_insert_buffer_size=8,388,608
character_set_client=utf8
character_set_connection=utf8
character_set_database=latin1
character_set_filesystem=binary
character_set_results=utf8
character_set_server=latin1
character_set_system=utf8
character_sets_dir=/usr/share/mysql/charsets/
collation_connection=utf8_general_ci
collation_database=latin1_swedish_ci
collation_server=latin1_swedish_ci
completion_type=NO_CHAIN
concurrent_insert=AUTO
connect_timeout=10
core_file=OFF
datadir=/var/lib/mysql/
date_format=%Y-%m-%d
datetime_format=%Y-%m-%d_%H:%i:%s
default_storage_engine=InnoDB
default_tmp_storage_engine=InnoDB
default_week_format=0
delay_key_write=ON
delayed_insert_limit=100
delayed_insert_timeout=300
delayed_queue_size=1,000
disconnect_on_expired_password=ON
div_precision_increment=4
end_markers_in_json=OFF
enforce_gtid_consistency=OFF
eq_range_index_dive_limit=10
error_count=0
event_scheduler=OFF
expire_logs_days=10
explicit_defaults_for_timestamp=OFF
external_user=
flush=OFF
flush_time=0
foreign_key_checks=ON
ft_boolean_syntax=+_-><()~*:""&|
ft_max_word_len=84
ft_min_word_len=4
ft_query_expansion_limit=20
ft_stopword_file=(built-in)
general_log=OFF
general_log_file=/var/log/mysql/mysql.log
group_concat_max_len=1,024
gtid_executed=
gtid_mode=OFF
gtid_next=AUTOMATIC
gtid_owned=
gtid_purged=
have_compress=YES
have_crypt=YES
have_dynamic_loading=YES
have_geometry=YES
have_openssl=DISABLED
have_profiling=YES
have_query_cache=YES
have_rtree_keys=YES
have_ssl=DISABLED
have_symlink=YES
host_cache_size=328
hostname=mysqlhost.com
identity=0
ignore_builtin_innodb=OFF
ignore_db_dirs=
init_connect=
init_file=
init_slave=
innodb_adaptive_flushing=ON
innodb_adaptive_flushing_lwm=10
innodb_adaptive_hash_index=ON
innodb_adaptive_max_sleep_delay=150,000
innodb_additional_mem_pool_size=8,388,608
innodb_api_bk_commit_interval=5
innodb_api_disable_rowlock=OFF
innodb_api_enable_binlog=OFF
innodb_api_enable_mdl=OFF
innodb_api_trx_level=0
innodb_autoextend_increment=64
innodb_autoinc_lock_mode=1
innodb_buffer_pool_dump_at_shutdown=OFF
innodb_buffer_pool_dump_now=OFF
innodb_buffer_pool_filename=ib_buffer_pool
innodb_buffer_pool_instances=8
innodb_buffer_pool_load_abort=OFF
innodb_buffer_pool_load_at_startup=OFF
innodb_buffer_pool_load_now=OFF
innodb_buffer_pool_size=2,147,483,648
innodb_change_buffer_max_size=50
innodb_change_buffering=all
innodb_checksum_algorithm=innodb
innodb_checksums=ON
innodb_cmp_per_index_enabled=OFF
innodb_commit_concurrency=0
innodb_compression_failure_threshold_pct=5
innodb_compression_level=6
innodb_compression_pad_pct_max=50
innodb_concurrency_tickets=5,000
innodb_data_file_path=ibdata1:12M:autoextend
innodb_data_home_dir=
innodb_disable_sort_file_cache=OFF
innodb_doublewrite=ON
innodb_fast_shutdown=1
innodb_file_format=Antelope
innodb_file_format_check=ON
innodb_file_format_max=Antelope
innodb_file_per_table=ON
innodb_flush_log_at_timeout=1
innodb_flush_log_at_trx_commit=1
innodb_flush_method=O_DIRECT
innodb_flush_neighbors=1
innodb_flushing_avg_loops=30
innodb_force_load_corrupted=OFF
innodb_force_recovery=0
innodb_ft_aux_table=
innodb_ft_cache_size=8,000,000
innodb_ft_enable_diag_print=OFF
innodb_ft_enable_stopword=ON
innodb_ft_max_token_size=84
innodb_ft_min_token_size=3
innodb_ft_num_word_optimize=2,000
innodb_ft_result_cache_limit=2,000,000,000
innodb_ft_server_stopword_table=
innodb_ft_sort_pll_degree=2
innodb_ft_total_cache_size=640,000,000
innodb_ft_user_stopword_table=
innodb_io_capacity=200
innodb_io_capacity_max=2,000
innodb_large_prefix=OFF
innodb_lock_wait_timeout=50
innodb_locks_unsafe_for_binlog=OFF
innodb_log_buffer_size=33,554,432
innodb_log_compressed_pages=ON
innodb_log_file_size=134,217,728
innodb_log_files_in_group=2
innodb_log_group_home_dir=./
innodb_lru_scan_depth=1,024
innodb_max_dirty_pages_pct=75
innodb_max_dirty_pages_pct_lwm=25
innodb_max_purge_lag=0
innodb_max_purge_lag_delay=0
innodb_mirrored_log_groups=1
innodb_monitor_disable=
innodb_monitor_enable=
innodb_monitor_reset=
innodb_monitor_reset_all=
innodb_old_blocks_pct=37
innodb_old_blocks_time=1,000
innodb_online_alter_log_max_size=134,217,728
innodb_open_files=2,000
innodb_optimize_fulltext_only=OFF
innodb_page_size=16,384
innodb_print_all_deadlocks=OFF
innodb_purge_batch_size=300
innodb_purge_threads=1
innodb_random_read_ahead=OFF
innodb_read_ahead_threshold=56
innodb_read_io_threads=4
innodb_read_only=OFF
innodb_replication_delay=0
innodb_rollback_on_timeout=OFF
innodb_rollback_segments=128
innodb_sort_buffer_size=1,048,576
innodb_spin_wait_delay=6
innodb_stats_auto_recalc=ON
innodb_stats_method=nulls_equal
innodb_stats_on_metadata=OFF
innodb_stats_persistent=ON
innodb_stats_persistent_sample_pages=20
innodb_stats_sample_pages=8
innodb_stats_transient_sample_pages=8
innodb_status_output=OFF
innodb_status_output_locks=OFF
innodb_strict_mode=OFF
innodb_support_xa=ON
innodb_sync_array_size=1
innodb_sync_spin_loops=30
innodb_table_locks=ON
innodb_thread_concurrency=0
innodb_thread_sleep_delay=10,000
innodb_tmpdir=
innodb_undo_directory=.
innodb_undo_logs=128
innodb_undo_tablespaces=0
innodb_use_native_aio=OFF
innodb_use_sys_malloc=ON
innodb_version=5.6.31
innodb_write_io_threads=4
insert_id=0
interactive_timeout=28,800
join_buffer_size=4,194,304
keep_files_on_create=OFF
key_buffer_size=301,989,888
key_cache_age_threshold=300
key_cache_block_size=1,024
key_cache_division_limit=100
large_files_support=ON
large_page_size=0
large_pages=OFF
last_insert_id=0
lc_messages=en_US
lc_messages_dir=/usr/share/mysql/
lc_time_names=en_US
license=GPL
local_infile=ON
lock_wait_timeout=31,536,000
locked_in_memory=OFF
log_bin=OFF
log_bin_basename=
log_bin_index=
log_bin_trust_function_creators=OFF
log_bin_use_v1_row_events=OFF
log_error=/var/log/mysql/error.log
log_output=FILE
log_queries_not_using_indexes=OFF
log_slave_updates=OFF
log_slow_admin_statements=OFF
log_slow_slave_statements=OFF
log_throttle_queries_not_using_indexes=0
log_warnings=2
long_query_time=10
low_priority_updates=OFF
lower_case_file_system=OFF
lower_case_table_names=0
master_info_repository=FILE
master_verify_checksum=OFF
max_allowed_packet=16,777,216
max_binlog_cache_size=18446744073709547520
max_binlog_size=1,073,741,824
max_binlog_stmt_cache_size=18446744073709547520
max_connect_errors=10,000
max_connections=200
max_delayed_threads=20
max_digest_length=1,024
max_error_count=64
max_heap_table_size=134,217,728
max_insert_delayed_threads=20
max_join_size=18446744073709551615
max_length_for_sort_data=1,024
max_prepared_stmt_count=16,382
max_relay_log_size=0
max_seeks_for_key=18446744073709551615
max_sort_length=1,024
max_sp_recursion_depth=0
max_tmp_tables=32
max_user_connections=0
max_write_lock_count=18446744073709551615
metadata_locks_cache_size=1,024
metadata_locks_hash_instances=8
min_examined_row_limit=0
multi_range_count=256
myisam_data_pointer_size=6
myisam_max_sort_file_size=9223372036853727232
myisam_mmap_size=18446744073709551615
myisam_recover_options=BACKUP,FORCE
myisam_repair_threads=1
myisam_sort_buffer_size=8,388,608
myisam_stats_method=nulls_unequal
myisam_use_mmap=OFF
net_buffer_length=16,384
net_read_timeout=30
net_retry_count=10
net_write_timeout=60
new=OFF
old=OFF
old_alter_table=OFF
old_passwords=0
open_files_limit=10,000
optimizer_prune_level=1
optimizer_search_depth=62
optimizer_switch=index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,engine_condition_pushdown=on,index_condition_pushdown=on,mrr=on,mrr_cost_based=on,block_nested_loop=on,batched_key_access=off,materialization=on,semijoin=on,loosescan=on,firstmatch=on,subquery_materialization_cost_based=on,use_index_extensions=on
optimizer_trace=enabled=off,one_line=off
optimizer_trace_features=greedy_search=on,range_optimizer=on,dynamic_range=on,repeated_subselect=on
optimizer_trace_limit=1
optimizer_trace_max_mem_size=16,384
optimizer_trace_offset=-1
performance_schema=OFF
performance_schema_accounts_size=-1
performance_schema_digests_size=-1
performance_schema_events_stages_history_long_size=-1
performance_schema_events_stages_history_size=-1
performance_schema_events_statements_history_long_size=-1
performance_schema_events_statements_history_size=-1
performance_schema_events_waits_history_long_size=-1
performance_schema_events_waits_history_size=-1
performance_schema_hosts_size=-1
performance_schema_max_cond_classes=80
performance_schema_max_cond_instances=-1
performance_schema_max_digest_length=1,024
performance_schema_max_file_classes=50
performance_schema_max_file_handles=32,768
performance_schema_max_file_instances=-1
performance_schema_max_mutex_classes=200
performance_schema_max_mutex_instances=-1
performance_schema_max_rwlock_classes=40
performance_schema_max_rwlock_instances=-1
performance_schema_max_socket_classes=10
performance_schema_max_socket_instances=-1
performance_schema_max_stage_classes=150
performance_schema_max_statement_classes=168
performance_schema_max_table_handles=-1
performance_schema_max_table_instances=-1
performance_schema_max_thread_classes=50
performance_schema_max_thread_instances=-1
performance_schema_session_connect_attrs_size=-1
performance_schema_setup_actors_size=100
performance_schema_setup_objects_size=100
performance_schema_users_size=-1
pid_file=/var/run/mysqld/mysqld.pid
plugin_dir=/usr/lib/mysql/plugin/
port=3,306
preload_buffer_size=32,768
profiling=OFF
profiling_history_size=15
protocol_version=10
proxy_user=
pseudo_slave_mode=OFF
pseudo_thread_id=517,506
query_alloc_block_size=8,192
query_cache_limit=5,242,880
query_cache_min_res_unit=4,096
query_cache_size=52,428,800
query_cache_type=OFF
query_cache_wlock_invalidate=OFF
query_prealloc_size=8,192
rand_seed1=0
rand_seed2=0
range_alloc_block_size=4,096
read_buffer_size=1,048,576
read_only=OFF
read_rnd_buffer_size=262,144
relay_log=
relay_log_basename=
relay_log_index=
relay_log_info_file=relay-log.info
relay_log_info_repository=FILE
relay_log_purge=ON
relay_log_recovery=OFF
relay_log_space_limit=0
report_host=
report_password=
report_port=3,306
report_user=
rpl_stop_slave_timeout=31,536,000
secure_auth=ON
secure_file_priv=
server_id=0
server_id_bits=32
server_uuid=993bf09d-45a2-11e6-98f0-fa163ecd49dc
show_old_temporals=OFF
simplified_binlog_gtid_recovery=OFF
skip_external_locking=ON
skip_name_resolve=OFF
skip_networking=OFF
skip_show_database=OFF
slave_allow_batching=OFF
slave_checkpoint_group=512
slave_checkpoint_period=300
slave_compressed_protocol=OFF
slave_exec_mode=STRICT
slave_load_tmpdir=/tmp
slave_max_allowed_packet=1,073,741,824
slave_net_timeout=3,600
slave_parallel_workers=0
slave_pending_jobs_size_max=16,777,216
slave_rows_search_algorithms=TABLE_SCAN,INDEX_SCAN
slave_skip_errors=OFF
slave_sql_verify_checksum=ON
slave_transaction_retries=10
slave_type_conversions=
slow_launch_time=2
slow_query_log=ON
slow_query_log_file=/var/log/mysql/mysql-slow.log
socket=/var/run/mysqld/mysqld.sock
sort_buffer_size=2,097,152
sql_auto_is_null=OFF
sql_big_selects=ON
sql_buffer_result=OFF
sql_log_bin=ON
sql_log_off=OFF
sql_mode=NO_ENGINE_SUBSTITUTION
sql_notes=ON
sql_quote_show_create=ON
sql_safe_updates=OFF
sql_select_limit=18446744073709551615
sql_slave_skip_counter=0
sql_warnings=OFF
ssl_ca=
ssl_capath=
ssl_cert=
ssl_cipher=
ssl_crl=
ssl_crlpath=
ssl_key=
storage_engine=InnoDB
stored_program_cache=256
sync_binlog=0
sync_frm=ON
sync_master_info=10,000
sync_relay_log=10,000
sync_relay_log_info=10,000
system_time_zone=PDT
table_definition_cache=1,400
table_open_cache=2,000
table_open_cache_instances=1
thread_cache_size=64
thread_concurrency=10
thread_handling=one-thread-per-connection
thread_stack=262,144
time_format=%H:%i:%s
time_zone=SYSTEM
timed_mutexes=OFF
timestamp=1473081753.003525
tmp_table_size=134,217,728
tmpdir=/tmp
transaction_alloc_block_size=8,192
transaction_allow_batching=OFF
transaction_prealloc_size=4,096
tx_isolation=REPEATABLE-READ
tx_read_only=OFF
unique_checks=ON
updatable_views_with_limit=YES
version=5.6.31-0ubuntu0.14.04.2-log
version_comment=(Ubuntu)
version_compile_machine=x86_64
version_compile_os=debian-linux-gnu
wait_timeout=28,800
warning_count=0
MySQL v5.6 ...对不起，我感到困惑 –
您是否正在更新很多索引列？ –
没有那么多。在盛大的计划中，可能少于5％的更新进入具有多个索引的表格中。 –