Mysql 實作資料庫讀寫分離-有解無憂

Amoeba+Mysql實作資料庫讀寫分離

一、Amoeba 是什么

Amoeba(變形蟲)專案，專注分布式資料庫 proxy 開發，座落與Client、DB Server(s)之間，對客戶端透明，具有負載均衡、高可用性、sql過濾、讀寫分離、可路由相關的query到目標資料庫、可并發請求多臺資料庫合并結果，

主要解決：

? 降低資料切分帶來的復雜多資料庫結構

? 提供切分規則并降低資料切分規則給應用帶來的影響

? 降低db 與客戶端的連接數

? 讀寫分離

二、為什么要用Amoeba

目前要實作mysql的主從讀寫分離，主要有以下幾種方案：

1、通程序式實作，網上很多現成的代碼，比較復雜，如果添加從服務器要更改多臺服務器的代碼，

2、通過mysql-proxy來實作，由于mysql-proxy的主從讀寫分離是通過lua腳本來實作，目前lua的腳本的開發跟不上節奏，而寫沒有完美的現成的腳本，因此導致用于生產環境的話風險比較大，據網上很多人說mysql-proxy的性能不高，

3、自己開發介面實作，這種方案門檻高，開發成本高，不是一般的小公司能承擔得起，

4、利用阿里巴巴的開源專案Amoeba來實作，具有負載均衡、高可用性、sql過濾、讀寫分離、可路由相關的query到目標資料庫，并且安裝配置非常簡單，國產的開源軟體，應該支持，目前正在使用，不發表太多結論，一切等測驗完再發表結論吧，哈哈！

三、Amoeba+Mysql實作資料庫讀寫分離

基本的原理：讓“主”資料庫處理事務增，刪，改（INSERT，UPDATA，DELETE），“從”資料庫處理SELECT查詢操作，資料庫復制被用來把事務性操作導致變更同步到集群中的從資料庫

先介紹下部署環境：

amoeba（代理服務器）:192.168.220.33

master-mysql：192.168.220.30

slave1-mysql：192.168.220.31

slave2-mysql：192.168.220.32

客戶機（本機 win11）：192.168.220.2

系統：centOS 7.9

MySQL：5.7

Amoeba：3.0.5 （框架是居于java語言開發）

jdk：1.8

部署MySQL一主多從：

注：做主從資料庫里資料最好是保持一致

1、主資料庫：master-mysql

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec)

mysql> 
mysql> grant all on *.* to 'test'@'192.168.220.%' identified by '1234.Com'; #創建授權用戶 為amoeba提供登錄
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql> 
mysql> grant replication slave on *.* to 'slave'@'192.168.220.%' identified by '1234.Com'; #主從模式
Query OK, 0 rows affected, 1 warning (0.00 sec)

mysql>
mysql> show master status\G;
*************************** 1. row ***************************
             File: mysql-bin.000001 #從庫加入主庫時 需要配置的二進制檔案名
         Position: 154 　　　　　　　 # 二進制日子 從 pos 154 開始被slave
復制
備份 Binlog_Do_DB: Binlog_Ignore_DB: Executed_Gtid_Set: 1 row in set (0.00 sec) ERROR: No query specified mysql>

2、從資料庫：slave1-mysql

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec)

mysql> 
mysql> change master to master_host='192.168.220.30',master_user='slave',master_password='1234.Com',,master_log_file='mysql-bin.000001',master_log_pos=154；
Query OK, 0 rows affected, 2 warnings (0.01 sec)

mysql> 
mysql> start slave;
Query OK, 0 rows affected (0.01 sec)

mysql> show slave status\G; #查看從庫的連接狀態，I/O，SQL 都要為 YES
*************************** 1. row ***************************
               Slave_IO_State: Connecting to master
                  Master_Host: 192.168.220.30
                  Master_User: slave
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000001
          Read_Master_Log_Pos: 154
               Relay_Log_File: slave1-relay-bin.000001
                Relay_Log_Pos: 4
        Relay_Master_Log_File: mysql-bin.000001
             Slave_IO_Running: YES 
            Slave_SQL_Running: Yes
              Replicate_Do_DB: 

       ····················

ERROR: 
No query specified

mysql> grant all on *.* to 'test'@'192.168.220.%' identified by '1234.Com'; #創建授權用戶 為amoeba提供登錄
Query OK, 0 rows affected, 1 warning (0.00 sec)

3、從資料庫：slave2-mysql

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec)



mysql> 
mysql> change master to master_host='192.168.220.30',master_user='slave',master_password='1234.Com',,master_log_file='mysql-bin.000001',master_log_pos=154；
Query OK, 0 rows affected, 2 warnings (0.01 sec)

mysql> 
mysql> start slave;
Query OK, 0 rows affected (0.01 sec)

mysql> show slave status\G; #查看從庫的連接狀態，I/O，SQL 都要為 YES
*************************** 1. row ***************************
               Slave_IO_State: Connecting to master
                  Master_Host: 192.168.220.30
                  Master_User: slave
                  Master_Port: 3306
                Connect_Retry: 60
              Master_Log_File: mysql-bin.000001
          Read_Master_Log_Pos: 154
               Relay_Log_File: slave1-relay-bin.000001
                Relay_Log_Pos: 4
        Relay_Master_Log_File: mysql-bin.000001
             Slave_IO_Running: YES 
            Slave_SQL_Running: Yes
              Replicate_Do_DB: 

       ····················

ERROR: 
No query specified

mysql> grant all on *.* to 'test'@'192.168.220.%' identified by '1234.Com'; #創建授權用戶 為amoeba提供登錄
Query OK, 0 rows affected, 1 warning (0.00 sec)

4、主庫測驗：創建一個測驗庫并添加創建表和添加資料，查看從庫是否同步

mysql> create database test; 
Query OK, 1 row affected (0.00 sec)

mysql> use test;
Database changed

mysql> create table test (id int);
Query OK, 0 rows affected (0.01 sec)

mysql> insert into test values (1);
Query OK, 1 row affected (0.00 sec)

mysql> select * from test;
+------+
| id   |
+------+
|    1 |
+------+
1 row in set (0.00 sec)

mysql>

5、slave1 從庫測驗：

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| test               |
+--------------------+
5 rows in set (0.00 sec)

mysql> select * from test.test;
+------+
| id   |
+------+
|    1 |
+------+
1 row in set (0.00 sec)

mysql>

6、slave2 從庫測驗：

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
| test               |
+--------------------+
5 rows in set (0.00 sec)

mysql> select * from test.test;
+------+
| id   |
+------+
|    1 |
+------+
1 row in set (0.00 sec)

mysql>

從資料庫同步正常，主從資料庫部署完成，接下來部署 Amoeba

Amoeba 安裝部署

1、安裝java環境

先去官網下載：http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

安裝

[root@amoeba src]# rpm -ivh jdk-8u111-linux-x64.rpm
Preparing...                ########################################### [100%]
   1:jdk1.8.0_111           ########################################### [100%]
Unpacking JAR files...
    tools.jar...
    plugin.jar...
    javaws.jar...
    deploy.jar...
    rt.jar...
    jsse.jar...
    charsets.jar...
    localedata.jar...

設定Java環境

[root@amoeba src]# vim /etc/profile

#set java environment
JAVA_HOME=/usr/java/jdk1.8.0_111
JRE_HOME=/usr/java/jdk1.8.0_111/jre
CLASS_PATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib
PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
export JAVA_HOME JRE_HOME CLASS_PATH PATH[root@bogon amoeba]# source /etc/profile

測驗是否安裝成功

[root@bogon src]# java -version
java version "1.8.0_111"
Java(TM) SE Runtime Environment (build 1.8.0_111-b14)
Java HotSpot(TM) 64-Bit Server VM (build 25.111-b14, mixed mode)

2、安裝Amoeba

可以從https://sourceforge.net/projects/amoeba/files/Amoeba%20for%20mysql/3.x/下載最新版本的Amoeba，我這里下載的是amoeba-mysql-3.0.5-RC-distribution.zip，Amoeba安裝非常簡單，直接解壓即可使用，這里將Amoeba解壓到/usr/local/amoeba目錄下，這樣就安裝完成了

[root@amoeba amoeba]# pwd
/usr/local/amoeba
[root@amoeba amoeba]# ll
total 48
drwxr-xr-x 2 root root    63 Aug 16 10:24 benchmark
drwxr-xr-x 2 root root   131 Feb 29  2012 bin
-rwxr-xr-x 1 root root  3976 Aug 29  2012 changelogs.txt
drwxr-xr-x 2 root root   243 Aug 16 14:53 conf
drwxr-xr-x 3 root root  4096 Aug 16 10:24 lib
-rwxr-xr-x 1 root root 34520 Aug 29  2012 LICENSE.txt
drwxr-xr-x 2 root root   133 Aug 16 10:25 logs
-rwxr-xr-x 1 root root  2031 Aug 29  2012 README.html
[root@amoeba amoeba]#

3.配置Amoeba（實作讀寫分離，兩個slave“讀”負載）

Amoeba的組態檔在本環境下位于：/usr/local/amoeba/conf 目錄下，實作讀寫分離和負載只需要 dbServers.xml和amoeba.xml 兩個檔案即可，下面介紹

dbServer.xml

[root@amoeba amoeba]# cd conf/
[root@amoeba conf]# ls
access_list.conf  amoeba.xml    dbServers.xml  functionMap.xml  log4j.xml  ruleFunctionMap.xml
amoeba.dtd        dbserver.dtd  function.dtd   log4j.dtd        rule.dtd   rule.xml
[root@amoeba conf]# cat dbServers.xml 
<?xml version="1.0" encoding="gbk"?>

<!DOCTYPE amoeba:dbServers SYSTEM "dbserver.dtd">
<amoeba:dbServers xmlns:amoeba="http://amoeba.meidusa.com/">

        <!-- 
            Each dbServer needs to be configured into a Pool,
            If you need to configure multiple dbServer with load balancing that can be simplified by the following configuration:
             add attribute with name virtual = "true" in dbServer, but the configuration does not allow the element with name factoryConfig
             such as 'multiPool' dbServer   
        -->
        
    <dbServer name="abstractServer" abstractive="true">
        <factoryConfig class="com.meidusa.amoeba.mysql.net.MysqlServerConnectionFactory">
            <property name="manager">${defaultManager}</property>
            <property name="sendBufferSize">64</property>
            <property name="receiveBufferSize">128</property>
                
            <!-- mysql port -->
            <property name="port">3306</property>  #設定Amoeba 連接資料庫的埠，默認 3306
            
            <!-- mysql schema -->
            <property name="schema">mysql</property>  #設定 預設的資料庫，我這里使用的MySQL版本為5.7版本，默認是沒有test庫的，會報所以找不到默認的庫，我之前搭建的MySQL版本是5.5是不需要修改的，沒注意到這一點
            
            <!-- mysql user -->
            <property name="user">test</property>  #設定amoeba連接后端資料庫服務器的賬號和密碼，上面已為 test 授權 和設定了密碼
            
            <!--  mysql password -->
            <property name="password">1234.Com</property>

        </factoryConfig>

        <poolConfig class="com.meidusa.amoeba.net.poolable.PoolableObjectPool">
            <property name="maxActive">500</property>  #最大連接數，默認為500
            <property name="maxIdle">500</property>　　#最大空閑連接數
            <property name="minIdle">10</property>　　#最新空閑連接數
            <property name="minEvictableIdleTimeMillis">600000</property>
            <property name="timeBetweenEvictionRunsMillis">600000</property>
            <property name="testOnBorrow">true</property>
            <property name="testOnReturn">true</property>
            <property name="testWhileIdle">true</property>
        </poolConfig>
    </dbServer>

    <dbServer name="master"  parent="abstractServer">  #設定一個空間名稱，可任意命名，這里定義為：master，顧名思義就是為master庫創建一個命名空間，后面會用到
        <factoryConfig>
            <!-- mysql ip -->
            <property name="ipAddress">192.168.220.30</property> #設定 master的IP，功能可寫
        </factoryConfig>
    </dbServer>
    
    <dbServer name="slave1"  parent="abstractServer">  #設定slava1 命名空間名稱
        <factoryConfig>
            <!-- mysql ip -->
            <property name="ipAddress">192.168.220.31</property> # 設定slave1的IP，功能可寫
        </factoryConfig>
    </dbServer>
    <dbServer name="slave2"  parent="abstractServer"> #設定slava2 命名空間名稱
        <factoryConfig>
            <!-- mysql ip -->
            <property name="ipAddress">192.168.220.32</property>  #設定 slave的ip，功能可寫
        </factoryConfig>
    </dbServer>
    
    <dbServer name="slaves" virtual="true">  #設定定義一個虛擬的dbserver，實際上相當于一個dbserver組，這里將可讀的資料庫ip統一放到一個組中，將這個組的名字命名為slaves
        <poolConfig class="com.meidusa.amoeba.server.MultipleServerPool">
            <!-- Load balancing strategy: 1=ROUNDROBIN , 2=WEIGHTBASED , 3=HA-->
            <property name="loadbalance">1</property> #選擇調度演算法，1表示復制均衡，2表示權重，3表示HA， 這里選擇1
            
            <!-- Separated by commas,such as: server1,server2,server1 -->
            <property name="poolNames">slave1,slave2</property>  #slave組成員，把slave1，slave2 加入成員里，可實作 “讀” 負載
        </poolConfig>
    </dbServer>
        
</amoeba:dbServers>
[root@amoeba conf]#

amoeba.xml

[root@amoeba amoeba]# cd conf/
[root@amoeba conf]# ls
access_list.conf  amoeba.xml    dbServers.xml  functionMap.xml  log4j.xml  ruleFunctionMap.xml
amoeba.dtd        dbserver.dtd  function.dtd   log4j.dtd        rule.dtd   rule.xml
[root@amoeba conf]# cat amoeba.xml 
<?xml version="1.0" encoding="gbk"?>

<!DOCTYPE amoeba:configuration SYSTEM "amoeba.dtd">
<amoeba:configuration xmlns:amoeba="http://amoeba.meidusa.com/">

    <proxy>
    
        <!-- service class must implements com.meidusa.amoeba.service.Service -->
        <service name="Amoeba for Mysql" class="com.meidusa.amoeba.net.ServerableConnectionManager">
            <!-- port -->
            <property name="port">8066</property>  #設定amoeba 今天的埠，默認是8066
            
            <!-- bind ipAddress -->
            <!-- 
            <property name="ipAddress">127.0.0.1</property>
             -->
            
            <property name="manager">${clientConnectioneManager}</property>
            
            <property name="connectionFactory">
                <bean class="com.meidusa.amoeba.mysql.net.MysqlClientConnectionFactory">
                    <property name="sendBufferSize">128</property>
                    <property name="receiveBufferSize">64</property>
                </bean>
            </property>
            
            <property name="authenticator">
                <bean class="com.meidusa.amoeba.mysql.server.MysqlClientAuthenticator">
                    
                    <property name="user">amoeba</property>  #提供客服端連接amoeba是需要使用設定的賬號，賬號密碼可任意設定和資料服務器里的密碼無關
                    
                    <property name="password">123456</property>
                    
                    <property name="filter">
                        <bean class="com.meidusa.amoeba.server.IPAccessController">
                            <property name="ipFile">${amoeba.home}/conf/access_list.conf</property>
                        </bean>
                    </property>
                </bean>
            </property>
            
        </service>
        
        <!-- server class must implements com.meidusa.amoeba.service.Service -->
        <service name="Amoeba Monitor Server" class="com.meidusa.amoeba.monitor.MonitorServer">
            <!-- port -->
            <!--  default value: random number
            <property name="port">9066</property>
            -->
            <!-- bind ipAddress -->
            <property name="ipAddress">127.0.0.1</property>
            <property name="daemon">true</property>
            <property name="manager">${clientConnectioneManager}</property>
            <property name="connectionFactory">
                <bean class="com.meidusa.amoeba.monitor.net.MonitorClientConnectionFactory"></bean>
            </property>
            
        </service>
        
        <runtime class="com.meidusa.amoeba.mysql.context.MysqlRuntimeContext">
            <!-- proxy server net IO Read thread size -->
            <property name="readThreadPoolSize">20</property>
            
            <!-- proxy server client process thread size -->
            <property name="clientSideThreadPoolSize">30</property>
            
            <!-- mysql server data packet process thread size -->
            <property name="serverSideThreadPoolSize">30</property>
            
            <!-- per connection cache prepared statement size  -->
            <property name="statementCacheSize">500</property>
            
            <!-- query timeout( default: 60 second , TimeUnit:second) -->
            <property name="queryTimeout">60</property>
        </runtime>
        
    </proxy>
    
    <!-- 
        Each ConnectionManager will start as thread
        manager responsible for the Connection IO read , Death Detection
    -->
    <connectionManagerList>
        <connectionManager name="clientConnectioneManager" class="com.meidusa.amoeba.net.MultiConnectionManagerWrapper">
            <property name="subManagerClassName">com.meidusa.amoeba.net.ConnectionManager</property>
            <!-- 
              default value is avaliable Processors 
            <property name="processors">5</property>
             -->
        </connectionManager>
        <connectionManager name="defaultManager" class="com.meidusa.amoeba.net.MultiConnectionManagerWrapper">
            <property name="subManagerClassName">com.meidusa.amoeba.net.AuthingableConnectionManager</property>
            
            <!-- 
              default value is avaliable Processors 
            <property name="processors">5</property>
             -->
        </connectionManager>
    </connectionManagerList>
    
        <!-- default using file loader -->
    <dbServerLoader class="com.meidusa.amoeba.context.DBServerConfigFileLoader">
        <property name="configFile">${amoeba.home}/conf/dbServers.xml</property>
    </dbServerLoader>
    
    <queryRouter class="com.meidusa.amoeba.mysql.parser.MysqlQueryRouter">
        <property name="ruleLoader">
            <bean class="com.meidusa.amoeba.route.TableRuleFileLoader">
                <property name="ruleFile">${amoeba.home}/conf/rule.xml</property>
                <property name="functionFile">${amoeba.home}/conf/ruleFunctionMap.xml</property>
            </bean>
        </property>
        <property name="sqlFunctionFile">${amoeba.home}/conf/functionMap.xml</property>
        <property name="LRUMapSize">1500</property>
        <property name="defaultPool">master</property>  #設定amoeba默認是的池，這里設定為master（在dbServers.xml檔案中，我們定義了一會master的空間名稱以及對應的服務器IP）
        
        <property name="writePool">master</property>  #設定寫的池，master作為主資料庫，處理的業務為 增，刪，改 都是寫操作，所以這設定為master
        <property name="readPool">slaves</property>   #設定讀的池  slave 作為從庫，負責 查（SELECT，因為我們有兩個slave，在定義命名空間時，我們配置了一個slaves組，里面有slave1，slave2兩個成員，這樣就可以達到 讀的負載
        <property name="needParse">true</property>

    </queryRouter>
</amoeba:configuration>

3、啟動Amoeba

[root@amoeba ~]# /usr/local/amoeba/bin/launcher &
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchStandard(Launcher.java:329)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:239)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:409)
    at org.codehaus.classworlds.Launcher.mainWithExitCode(Launcher.java:127)
    at org.codehaus.classworlds.Launcher.main(Launcher.java:110)
Caused by: com.meidusa.toolkit.common.bean.util.InitialisationException: default pool required!,defaultPool=writedb invalid
    at com.meidusa.amoeba.route.AbstractQueryRouter.init(AbstractQueryRouter.java:469)
    at com.meidusa.amoeba.context.ProxyRuntimeContext.initAllInitialisableBeans(ProxyRuntimeContext.java:337)
    ... 11 more
 2022-8-16 18:46:37 [INFO] Project Name=Amoeba-MySQL, PID=1577 , System shutdown ....
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option PermSize=16m; support was removed in 8.0
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize=96m; support was removed in 8.0
2022-8-16 18:50:19 [INFO] Project Name=Amoeba-MySQL, PID=1602 , starting...
log4j:WARN log4j config load completed from file:/usr/local/amoeba/conf/log4j.xml
2022-8-16 18:50:21,668 INFO  context.MysqlRuntimeContext - Amoeba for Mysql current versoin=5.1.45-mysql-amoeba-proxy-3.0.4-BETA
log4j:WARN ip access config load completed from file:/usr/local/amoeba/conf/access_list.conf
2022-8-16 18:50:22,852 INFO  net.ServerableConnectionManager - Server listening on 0.0.0.0/0.0.0.0:8066.

查看埠

[root@amoeba ~]# netstat -anpt | grep java
tcp6       0      0 127.0.0.1:13319         :::*                    LISTEN      21350/java          
tcp6       0      0 :::8066                 :::*                    LISTEN      21350/java

4、Amoeba 登錄測驗（客戶端-本機：win11）

測驗結果：登錄后所在的庫是“mysql”庫，可讀取，可寫入，到這里資料庫讀寫分離部，負載部署完成！！！

　　　下面就是讀寫分離的效果測驗：

四、測驗讀寫分離，負載效果

1、讀寫分離測驗：

　　測驗1 ：mysql-master down機，寫入報錯，讀正常

mysql-master：

[root@mysql_master ~]# systemctl stop mysqld

客服端：

mysql> select * from test;  #可正常查詢
+------+
| id   |
+------+
|    1 |
|    2 |
+------+
2 rows in set (0.00 sec)

mysql>
mysql> insert into test values (3);  
ERROR 2013 (HY000): Lost connection to MySQL server during query  #寫入失敗

　　測驗2 ：關閉兩臺slave，讀取失敗，插入成功

mysql-master

[root@mysql_master ~]# systemctl start mysqld

mysql-slave1

[root@slave1 ~]# systemctl stop mysqld

mysql-slave2

[root@slave2 ~]# systemctl stop mysqld

客服端：

mysql> insert into test values (3);
Query OK, 1 row affected (0.00 sec)

mysql> select * from test;
ERROR 2013 (HY000): Lost connection to MySQL server during query  #查詢失敗
mysql>

　　測驗3：開啟slava1，save2上的mysql，查看資料是否自動同步

mysql-slave1

[root@slave1 ~]# systemctl start mysqld

mysql-slave2

[root@slave2 ~]# systemctl start mysqld

客服端：

mysql> select * from test;
+------+
| id   |
+------+
|    1 |
|    2 |
|    3 |
+------+
4 rows in set (0.00 sec)

mysql>
mysql> insert into test values (4);
Query OK, 1 row affected (0.00 sec)

mysql> select * from test;
+------+
| id   |
+------+
|    1 |
|    2 |
|    3 |
|    4 |
+------+
5 rows in set (0.00 sec)

mysql>

讀寫分離測驗完畢！！！

2、slave “讀” 負載測驗：

mysql-slave1：在test表插入值：100

[root@slave1 ~]# mysql -uroot -p
Enter password:
mysql>
mysql> select * from test;
+------+
| id   |
+------+
|    1 |
|    2 |
|    3 |
|    4 |
+------+
4 rows in set (0.00 sec)

mysql> insert into test values (100);
Query OK, 1 row affected (0.00 sec)

mysql> select * from test;
+------+
| id   |
+------+
|    1 |
|    2 |
|    3 |
|    4 |
|  100 |
+------+
5 rows in set (0.00 sec)

mysql>

mysql-slave2：在test表插入值：200

[root@slave2 ~]# mysql -uroot -p
Enter password:
mysql>
mysql> select * from test;
+------+
| id   |
+------+
|    1 |
|    2 |
|    3 |
|    4 |
+------+
4 rows in set (0.00 sec)

mysql> insert into test values (200);
Query OK, 1 row affected (0.00 sec)

mysql> select * from test;
+------+
| id   |
+------+
|    1 |
|    2 |
|    3 |
|    4 |
|  200 |
+------+
5 rows in set (0.00 sec)

mysql>

客服端：

mysql> select * from test;
+------+
| id   |
+------+
|    1 |
|    2 |
|    3 |
|    4 |
|  200 |
+------+
5 rows in set (0.00 sec)

mysql> select * from test;
+------+
| id   |
+------+
|    1 |
|    2 |
|    3 |
|    4 |
|  100 |
+------+
5 rows in set (0.00 sec)

mysql> select * from test;
+------+
| id   |
+------+
|    1 |
|    2 |
|    3 |
|    4 |
|  200 |
+------+
5 rows in set (0.00 sec)

mysql> select * from test;
+------+
| id   |
+------+
|    1 |
|    2 |
|    3 |
|    4 |
|  100 |
+------+
5 rows in set (0.00 sec)

mysql>

分別在 slave1，slava2 上對test表插入不同的資料，通過客戶端查詢會發現，每一次查詢和上一次不同，這里就是完全體系了 “讀 ”負載的功能，

五、可能會報錯：

在使用amoeba連接資料庫時，報錯java.lang.Exception: poolName=slaves, no valid pools

到這里對資料庫的高可用架構實驗到此結束！！！

本文來自博客園，作者：xiao智，轉載請注明原文鏈接：https://www.cnblogs.com/yuwen01/p/16591876.html

轉載請註明出處，本文鏈接：https://www.uj5u.com/shujuku/502073.html

標籤：其他

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