mysql数据库环境优化
一、环境优化
1.1内存优化
由于数据库主机一般内存较大，因此采用huge page。而且尽量使用80%的内存，以空间换时间。
/etc/sysctl.conf配置参数：
vm.hugetlb_shm_group=3306
kernel.shmmax=243805679616
kernel.shmall=59522871
1.2虚拟内存优化
由于数据库对存取速度反应较大，因此关闭swap。
1.3网络优化
由于公司需要直接访问IDC机房中数据库，因此网络需要优化。
/etc/sysctl.conf配置参数：
net.core.somaxconn = 40000
net.ipv4.tcp_max_syn_backlog = 40000
net.ipv4.ip_local_port_range = 1024 65535
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_tw_recycle = 1
net.core.wmem_max=12582912
net.core.rmem_max=12582912
net.ipv4.tcp_rmem= 10240 87380 12582912
net.ipv4.tcp_wmem= 10240 87380 12582912
net.ipv4.tcp_window_scaling = 1
net.ipv4.tcp_timestamps = 1
net.ipv4.tcp_sack = 1
net.ipv4.tcp_no_metrics_save = 1
net.core.netdev_max_backlog = 5000
1.4IO优化
尽量减少对IO的限制。因此在保障硬盘读写正常的情况下，需要增加如下/etc/sysctl.conf参数：
fs.file-max = 1000000
/etc/security/limits.conf配置：
* soft nofile 65535
* hard nofile 65535
mysql hard memlock unlimited
mysql soft memlock unlimited
二、数据库优化
2.1源码编译优化
采用较优的编译参数：
-m64 -Ofast -flto -march=native -funroll-loops -mfpmath=sse -static -g
编译命令：
cmake .. -DCMAKE_CXX_FLAGS_DEBUG=="-DUNIV_DEBUG -DUNIV_SYNC_DEBUG" \
-DCMAKE_BUILD_TYPE=RelWithDebInfo \
-DCMAKE_C_FLAGS_RELWITHDEBINFO="-m64 -Ofast -flto -march=native -funroll-loops -mfpmath=sse -static -g" \
-DCMAKE_CXX_FLAGS_RELWITHDEBINFO="-m64 -Ofast -flto -march=native -funroll-loops -mfpmath=sse -static -g" \
-DBUILD_CONFIG=mysql_release \
-DFEATURE_SET=community \
-DWITH_EMBEDDED_SERVER=ON \
-DCMAKE_INSTALL_PREFIX=/usr/local/percona \
-DMYSQL_UNIX_ADDR=/tmp/mysql.sock \
-DMYSQL_DATADIR=/data/mysql/data \
-DSYSCONFDIR=/etc \
-DMYSQL_TCP_PORT=3306 \
-DWITH_ARCHIVE_STORAGE_ENGINE=1 \
-DWITH_BLACKHOLE_STORAGE_ENGINE=1 \
-DWITH_FEDERATED_STORAGE_ENGINE=1 \
-DWITH_MYISAM_STORAGE_ENGINE=1 \
-DWITH_PARTITION_STORAGE_ENGINE=1 \
-DWITH_PERFSCHEMA_STORAGE_ENGINE=1 \
-DWITH_READLINE=system \
-DENABLED_LOCAL_INFILE=1 \
-DDEFAULT_CHARSET=utf8 \
-DDEFAULT_COLLATION=utf8_general_ci \
-DWITH_EXTRA_CHARSETS=all \
-DWITH_FAST_MUTEXES=ON\
-DWITH_ATOMIC_LOCKS=rwlocks
2.2内存优化
尽量采用内存的80%，作为数据库内存空间。
配置参数：
innodb_buffer_pool_size=180G
join_buffer_size=32M
key_buffer_size=256M
read_buffer_size=8388608
read_rnd_buffer_size=4M
2.3连接池优化
采用连接池，以负载高并发的访问。
配置参数：
thread_handling=pool-of-threads
thread_pool_high_prio_mode=statements
thread_pool_max_threads=100000
thread_pool_size=48
thread_pool_oversubscribe=10
thread_pool_stall_limit=300
2.4IO优化
配置参数：
sync_binlog=1000
innodb_read_io_threads=48
innodb_thread_concurrency=0
innodb_use_native_aio=1
innodb_write_io_threads=48
innodb_flush_method=ALL_O_DIRECT
2.5网络优化
配置参数：
max_connections=1000
net_buffer_length=1M
2.6结构优化
对一些大表进行分区处理，如crm_consume、crm_consume_detail、crm_customer等，以优化查询。
2.7综合优化
/etc/my.cnf配置参数：
[mysqld]
audit_log_rotations=5
audit_log_rotate_on_size=20480000
slow_query_log=1
slow_query_log_file=/data/mysql/data/db4-slow.log
long_query_time=5
back_log=1024
big_tables=1
bind_address=0.0.0.0
binlog_cache_size=8M
binlog_format=row
basedir=/usr/local/percona
binlog_stmt_cache_size=8M
datadir=/data/mysql/data/
delayed_queue_size=10000
enforce-gtid-consistency=ON
default_time_zone=+8:00
event_scheduler=1
expire_logs_days=7
federated
gtid_mode=ON
innodb_additional_mem_pool_size=64M
innodb_buffer_pool_instances=16
metadata_locks_hash_instances=16
table_open_cache_instances=16
innodb_buffer_pool_size=180G
innodb_data_file_path=ibdata1:1024M:autoextend
innodb_data_home_dir=/data/mysql/data/
innodb_file_per_table=1
innodb_flush_log_at_trx_commit=2
innodb_autoinc_lock_mode=2
innodb_flush_method=ALL_O_DIRECT
innodb_flush_neighbors=0
innodb_io_capacity=1000
innodb_lock_wait_timeout=50
innodb_log_buffer_size=512M
innodb_log_file_size=4096M
innodb_log_files_in_group=3
innodb_log_group_home_dir=/data/mysql/data/
innodb_max_dirty_pages_pct=75
innodb_old_blocks_pct=30
innodb_old_blocks_time=1000
innodb_open_files=4096
innodb_purge_threads=1
innodb_random_read_ahead=1
innodb_read_io_threads=48
innodb_thread_concurrency=0
innodb_use_native_aio=1
innodb_write_io_threads=48
join_buffer_size=32M
key_buffer_size=256M
log-bin=mysql-bin
log-error=/var/log/mysql-error.log
log_output=FILE
log_slave_updates=1
max_allowed_packet=128M
max_connect_errors=10000000
max_connections=1000
max_heap_table_size=64M
max_tmp_tables=1024
myisam_recover=FORCE,BACKUP
myisam_sort_buffer_size=128M
net_buffer_length=1M
open_files_limit=65535
pid-file=/data/mysql/data/mysql.pid
port=3306
query_cache_size=0
query_cache_type=0
report_host=192.168.201.11
report_port=3306
read_buffer_size=8388608
read_rnd_buffer_size=4M
relay-log=mysql-relay-bin
log_warnings=9
sync_binlog=1000
rpl_semi_sync_master_enabled=1
rpl_semi_sync_master_timeout=1000
server-id=11
skip-external-locking
skip-name-resolve
socket=/tmp/mysql.sock
sort_buffer_size=16M
table_definition_cache=4096
transaction_isolation=read-committed
table_open_cache=16384
thread_cache_size=2048
thread_stack=1048576
tmp_table_size=64M
slave_net_timeout=30
master-info-repository=TABLE
relay-log-info-repository=TABLE
sync-master-info=1
slave-parallel-workers=4
binlog-checksum=CRC32
master-verify-checksum=1
slave-sql-verify-checksum=1
binlog-rows-query-log_events=1
thread_handling=pool-of-threads
thread_pool_high_prio_mode=statements
thread_pool_max_threads=100000
thread_pool_size=48
thread_pool_oversubscribe=10
thread_pool_stall_limit=300
innodb_monitor_enable = '%'
performance_schema = ON
performance_schema_instrument = '%=on'
三、性能测试
3.1基准测试
利用sysbench工具进行数据库oltp测试，得出测试结论如下：
OLTP test statistics:
queries performed:
read: 481348
write: 137528
other: 68764
total: 687640
transactions: 34382 (572.21 per sec.)
read/write requests: 618876 (10299.77 per sec.)
other operations: 68764 (1144.42 per sec.)
ignored errors: 0 (0.00 per sec.)
reconnects: 0 (0.00 per sec.)
General statistics:
total time: 60.0864s
total number of events: 34382
total time taken by event execution: 3842.8699s
response time:
min: 23.10ms
avg: 111.77ms
max: 323.79ms
approx. 95 percentile: 166.95ms
Threads fairness:
events (avg/stddev): 537.2188/9.58
execution time (avg/stddev): 60.0448/0.02
可知：
tps：572.21 per sec
qps：10299.77 per sec.
3.2优化后测试
最好的测试结论如下：
OLTP test statistics:
queries performed:
read: 7265944
write: 2075984
other: 1037992
total: 10379920
transactions: 518996 (864.91 per sec.)
read/write requests: 9341928 (15568.43 per sec.)
other operations: 1037992 (1729.83 per sec.)
ignored errors: 0 (0.00 per sec.)
reconnects: 0 (0.00 per sec.)
General statistics:
total time: 600.0560s
total number of events: 518996
total time taken by event execution: 38354.8485s
response time:
min: 6.49ms
avg: 73.90ms
max: 252.93ms
approx. 95 percentile: 118.04ms
Threads fairness:
events (avg/stddev): 8109.3125/1090.72
execution time (avg/stddev): 599.2945/0.45
可知：
tps：864.91 per sec
qps：15568.43 per sec
3.3SQL测试
采用单个SQL语句进行测试，性能也有很大的提升。
