SAS硬盤15000轉/s,數據庫內存64G或者32G,SATA硬盤轉速7500轉或10000轉/s
企業一般是4塊SSD做RAID10
mysql優化:二分配置的優化,八分sql語句的優化。
key_buffer_size:表示索引緩存的大小,mysql緩存在內存裏的。內存的80%。MyIsam表的配置
table_cache:同時打開表的數
query_cache_size:查詢緩衝區的大小
query_cache_type:表示查詢緩衝區開啓沒,0關閉1開啓
max_connecions:數據庫最大連接數,1234千,爲了防止請求太多把數據庫搞掛了
sort_buffer_size:排序緩衝區的大小,這個值越大排序就越快
Innodb_buffer_pool_size:表示Innodb類型的表和索引的最大緩存,也配內存的80%
附一個真實環境MySQL配置my.cnf內容,可以根據實際情況修改:
[client]
port = 3306
socket = /tmp/mysql.sock
[mysqld]
user = mysql
server_id = 10
port = 3306
socket = /tmp/mysql.sock
datadir = /data/mysql/data1
old_passwords = 1
lower_case_table_names = 1
character-set-server = utf8
default-storage-engine = MYISAM
log-bin = bin.log
log-error = error.log
pid-file = mysql.pid
long_query_time = 2
slow_query_log
slow_query_log_file = slow.log
binlog_cache_size = 4M
binlog_format = mixed
max_binlog_cache_size = 16M
max_binlog_size = 1G
expire_logs_days = 30
ft_min_word_len = 4
back_log = 512
max_allowed_packet = 64M
max_connections = 4096
max_connect_errors = 100
join_buffer_size = 2M
read_buffer_size = 2M
read_rnd_buffer_size = 2M
sort_buffer_size = 2M
query_cache_size = 64M
table_open_cache = 10000
thread_cache_size = 256
max_heap_table_size = 64M
tmp_table_size = 64M
thread_stack = 192K
thread_concurrency = 24
local-infile = 0
skip-show-database
skip-name-resolve
skip-external-locking
connect_timeout = 600
interactive_timeout = 600
wait_timeout = 600
#*** MyISAM
key_buffer_size = 512M
bulk_insert_buffer_size = 64M
myisam_sort_buffer_size = 64M
myisam_max_sort_file_size = 1G
myisam_repair_threads = 1
concurrent_insert = 2
myisam_recover
#*** INNODB
innodb_buffer_pool_size = 16G
innodb_additional_mem_pool_size = 32M
innodb_data_file_path = ibdata1:1G;ibdata2:1G:autoextend
innodb_read_io_threads = 8
innodb_write_io_threads = 8
innodb_file_per_table = 1
innodb_flush_log_at_trx_commit = 2
innodb_lock_wait_timeout = 120
innodb_log_buffer_size = 8M
innodb_log_file_size = 256M
innodb_log_files_in_group = 3
innodb_max_dirty_pages_pct = 90
innodb_thread_concurrency = 16
innodb_open_files = 10000
#innodb_force_recovery = 4
#*** Replication Slave
read-only
#skip-slave-start
relay-log = relay.log
log-slave-updates
Mysql數據庫索引及慢查詢
1normal普通索引
2Unique不允許重複的索引,全文要只有這一個字段
3Full text全文搜索
建索引一般是DBA建
alter table class6 add index index_name(name);
alter table class6 add unique (name);
Alter table class6 add primary key (name);
或者使用create index index_name on table class6 (name);
刪除索引
drop index (index_name) on table_name;
alter table class6 drop index (index_name);
索引都是DBA用
慢查詢
查詢時間超過10秒,該語句就被記錄成慢查詢,然後拿給DBA給他優化
>Show variables like “%slow%”;看慢查詢狀態,查詢是否開啓,秒數設定,日誌開關,記錄到的目錄
開啓>set global slow_query_log=on或者off;
配置文件裏應該有這個設置,沒有的話去配置文件裏粘貼進去
log-slow-queries=/data/mysql/var/slow.log #日誌目錄。
long_query_time=0.1 # 記錄下查詢時間查過0.1秒。
log-queries-not-using-indexes # 表示記錄下沒有使用索引的查詢。
慢查詢特別重要,企業裏查詢時間超過0.1s記錄出來
mysqldumpslow -s r -t 1 /var/run/mysqld下的slow文件
Vim slow.log 把那裏面的文件給DBA就行了,他會去優化
show processlist;看目前進程任務
mysqladmin -uroot -p password newpassword 在外面改密碼
grep -r "192.168" * 過濾所有文件裏的字節