我有一个带
MySQL的Linux服务器,有：
-12 Gb RAM
-4 x Intel(R) Xeon(R) CPU E6510 @ 1.73GHz
-CentOS release 6.3
-MySQL 5.1.61
由于一些技术问题,我们不得不将服务器的RAM内存减少到8 GB,而现在,我们无法拥有任何内存.现在,正因为如此,我们的服务器上出现了很多性能问题.这是我们数据库的大小：
+--------+--------------------+---------+--------+--------+------------+---------+
| tables | table_schema | rows | data | idx | total_size | idxfrac |
+--------+--------------------+---------+--------+--------+------------+---------+
| 43 | XXXXXXXX | 142.81M | 10.52G | 13.31G | 23.83G | 1.27 |
| 44 | Test_XXXXXXXX | 55.20M | 3.57G | 4.77G | 8.33G | 1.34 |
| 34 | XXXXXXXXXXXXXXXX | 23.04M | 1.39G | 1.84G | 3.24G | 1.32 |
| 23 | mysql | 0.00M | 0.00G | 0.00G | 0.00G | 0.16 |
| 28 | information_schema | NULL | 0.00G | 0.00G | 0.00G | NULL |
+--------+--------------------+---------+--------+--------+------------+---------+
这是/etc/my.cnf的内容：
[mysqld]
max_allowed_packet = 1024M
sort_buffer_size = 512M
max_connections=500
query_cache_size = 512M
query_cache_limit = 512M
query-cache-type = 2
table_cache = 800
thread_cache_size=8
key_buffer_size = 512M
read_buffer_size=64M
read_rnd_buffer_size=64M
myisam_sort_buffer_size=64M
innodb_flush_log_at_trx_commit=2
innodb_buffer_pool_size=7000M
innodb_additional_mem_pool_size=100M
...
我不知道我是否能够真正确定大小和RAM之间的关系.但情况是,当我有12GB内存时,一切正常. “innodb_buffer_pool_size”值为10000M,性能非常好.但现在,采取相同的操作,如4倍.
我们的应用程序基本上是一个数据库导出器,主要只接受一个表,它有72,314,541个寄存器.
+--------+---------+--------+--------+------------+---------+
| tables | rows | data | idx | total_size | idxfrac |
+--------+---------+--------+--------+------------+---------+
| 9 | 159.12M | 11.07G | 15.87G | 26.94G | 1.43 |
+--------+---------+--------+--------+------------+---------+
目前我们正在测试更改“innodb_buffer_pool_size”的值,但看起来我们不会获得更多的表演.现在,问题是,我们可以做些什么来在我们的MySQL上获得更多性能？
-Put more RAM (obviously)
-Change more variables on /etc/my.cnf?
-MySQL Partitioning for Performance
-...
我们欢迎所有的想法和贡献,
提前致谢
编辑：添加了表和查询的所有信息
DB的结构是从一些传感器接收信息并存储它的系统.
测量表：我们从传感器接收的测量值.
+--------------------+------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+--------------------+------------+------+-----+---------+----------------+
| id | bigint(20) | NO | PRI | NULL | auto_increment |
| version | bigint(20) | NO | | NULL | |
| counter | char(2) | YES | | NULL | |
| datemeasurement_id | datetime | NO | MUL | NULL | |
| datereal_id | datetime | NO | MUL | NULL | |
| delayed | bit(1) | NO | | NULL | |
| frequency | tinyint(4) | YES | | NULL | |
| measuringentity_id | bigint(20) | NO | MUL | NULL | |
| real | bit(1) | NO | | NULL | |
| tamper | bit(1) | NO | | NULL | |
| value | float | NO | | NULL | |
+--------------------+------------+------+-----+---------+----------------+
measuring_entity表：一个传感器可以测量多个物体(温度,湿度).这些是实体.
+--------------+------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+--------------+------------+------+-----+---------+----------------+
| id | bigint(20) | NO | PRI | NULL | auto_increment |
| version | bigint(20) | NO | | NULL | |
| household_id | varchar(4) | NO | MUL | NULL | |
| operative | bit(1) | NO | | NULL | |
| type | char(20) | NO | | NULL | |
| unit | char(3) | NO | | NULL | |
| interval | float | YES | | NULL | |
+--------------+------------+------+-----+---------+----------------+
sensor_measuring_entity：一个传感器可以关联多个实体.
+--------------------+------------+------+-----+---------+-------+
| Field | Type | Null | Key | Default | Extra |
+--------------------+------------+------+-----+---------+-------+
| sensor_id | bigint(20) | NO | PRI | NULL | |
| measuringentity_id | bigint(20) | NO | PRI | NULL | |
| version | bigint(20) | NO | | NULL | |
+--------------------+------------+------+-----+---------+-------+
传感器表：传感器的信息,与上表中的测量实体相关.
+---------------------+-------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+---------------------+-------------+------+-----+---------+----------------+
| id | bigint(20) | NO | PRI | NULL | auto_increment |
| version | bigint(20) | NO | | NULL | |
| battery | bit(1) | NO | | NULL | |
| identifier | char(6) | NO | | NULL | |
| installationdate_id | datetime | NO | MUL | NULL | |
| lastreceiveddate_id | datetime | YES | MUL | NULL | |
| location_id | bigint(20) | NO | MUL | NULL | |
| operative | bit(1) | NO | | NULL | |
| tampererror | smallint(6) | NO | | NULL | |
+---------------------+-------------+------+-----+---------+----------------+
位置表：传感器放置在何处.
+------------+------------+------+-----+---------+----------------+
| Field | Type | Null | Key | Default | Extra |
+------------+------------+------+-----+---------+----------------+
| id | bigint(20) | NO | PRI | NULL | auto_increment |
| version | bigint(20) | NO | | NULL | |
| height | tinyint(4) | YES | | NULL | |
| operative | bit(1) | NO | | NULL | |
| place | char(15) | NO | MUL | NULL | |
| room | char(15) | NO | | NULL | |
| typesensor | char(15) | NO | | NULL | |
| formaster | bit(1) | YES | | NULL | |
+------------+------------+------+-----+---------+----------------+
这是查询(适用于所有房屋和所有传感器)：
for (int z = 0; z < allHouses.length; z++) {
for (int j = 0; j < sensorlist.length; j++) {
sql.eachRow ("SELECT m.datemeasurement_id, s.identifier, me.type, m.value"
+ " FROM measurement as m"
+ " JOIN measuring_entity as me ON m.measuringentity_id = me.id"
+ " JOIN sensor_measuring_entity as sme ON sme.measuringentity_id = me.id"
+ " JOIN sensor as s ON sme.sensor_id = s.id"
+ " WHERE me.id = $actualmeid"
+ " AND me.household_id = '$mHouse'"
+ " AND m.datemeasurement_id >= '$cons_startDate'"
+ " AND m.datemeasurement_id <= '$cons_endDate'"
+ " AND m.datemeasurement_id > '$startDate'"
+ " AND m.datemeasurement_id < '$endDate'"
+ " ORDER BY datemeasurement_id")
{
}}
PD：一切都是Grails应用程序的一部分.
最佳答案 您正在分配太多RAM并进行交换.交换比缩小设置要糟糕得多.
对于8GB,请推荐这些更改
innodb_buffer_pool_size = 5000M
query_cache_size = 50M
如果您说您使用的是MyISAM还是InnoDB,我会给您更多提示.
