mysql主从复制5.6基于GID及多线程的复制笔记

mysql:数据库复制过滤     #show grobal variables like 'binlog%';注意：不能在主服务器上做过滤，二进制不完整性；它将危害到其他的数据库；在从库过滤会占用过多的带宽,还会复制过多的跟数据库无关的内容主端:    binlog-do-db:仅将指定数据库的相关修改操作记为二进制日志(白名单)    binlog-ignore-db从端:    replicate-do-db=    #仅复制指定数据库的二进制日志文件    replicate-ignore-db= #忽略那数据库    replicate-do-table=    replicate-ignore-table=    replicate-wild-do-table=    replicate-wild-ignore-table=在从库中：修改配置文件：vim /etc/my.cnf    replicate-do-db = discuz#重启mysqlmysql> show variables like 'rep%';#查看repmysql> show slave status\G #查看slave的状态从库测试结果：mysql> show databases;+--------------------+| Database           |+--------------------+| information_schema || discuz 主库：创建一个数据库discuz；从库同步成功看上面的结果：2.1.1.mysql5.6数据库中有多个数据库时，多线程复制才有意义；MySQL-5.6: GTID     slave-parallel-workers=0  0: 表示禁用多线程功能；     MySQL 5.6引入的GTID(Global Transaction IDs)使得其复制功能的配置、监控及管理变得更加易于实现，且更加健壮。要在MySQL 5.6中使用复制功能，其服务配置段[mysqld]中于少应该定义如下选项：binlog-format：二进制日志的格式，有row、statement和mixed几种类型； 需要注意的是：当设置隔离级别为READ-COMMITED必须设置二进制日志格式为ROW，现在MySQL官方认为STATEMENT这个已经不再适合继续使用；但mixed类型在默认的事务隔离级别下，可能会导致主从数据不一致； log-slave-updates、gtid-mode、enforce-gtid-consistency、report-port和report-host：用于启动GTID及满足附属的其它需求；master-info-repository和relay-log-info-repository：启用此两项，可用于实现在崩溃时保证二进制及从服务器安全的功能；sync-master-info：启用之可确保无信息丢失；slave-paralles-workers：设定从服务器的SQL线程数；0表示关闭多线程复制功能；binlog-checksum、master-verify-checksum和slave-sql-verify-checksum：启用复制有关的所有校验功能；binlog-rows-query-log-events：启用之可用于在二进制日志记录事件相关的信息，可降低故障排除的复杂度； log-bin：启用二进制日志，这是保证复制功能的基本前提；server-id：同一个复制拓扑中的所有服务器的id号必须惟一；一、简单主从模式配置步骤 1、配置主从节点的服务配置文件 1.1、配置master节点： [mysqld] binlog-format=ROW log-bin=master-bin log-slave-updates=true gtid-mode=on   #开启gtid功能enforce-gtid-consistency=true master-info-repository=TABLE relay-log-info-repository=TABLE sync-master-info=1 slave-parallel-workers=2 binlog-checksum=CRC32 master-verify-checksum=1 slave-sql-verify-checksum=1 binlog-rows-query-log_events=1 server-id=1 report-port=3306 port=3306 datadir=/mydata/data socket=/tmp/mysql.sock report-host=master.magedu.com 1.2、配置slave节点： [mysqld] binlog-format=ROW log-slave-updates=true gtid-mode=on enforce-gtid-consistency=true master-info-repository=TABLE relay-log-info-repository=TABLE sync-master-info=1 slave-parallel-workers=2 binlog-checksum=CRC32 master-verify-checksum=1 slave-sql-verify-checksum=1 binlog-rows-query-log_events=1 server-id=11 report-port=3306 port=3306 log-bin=mysql-bin.log datadir=/mydata/data socket=/tmp/mysql.sock report-host=slave.magedu.com 2、创建复制用户 mysql> GRANT REPLICATION SLAVE ON *.* TO [email protected] IDENTIFIED BY 'replpass'; 说明：172.16.100.7是从节点服务器；如果想一次性授权更多的节点，可以自行根据需要修改； 3、为备节点提供初始数据集 锁定主表，备份主节点上的数据，将其还原至从节点；如果没有启用GTID，在备份时需要在master上使用show master status命令查看二进制日志文件名称及事件位置，以便后面启动slave节点时使用。 4、启动从节点的复制线程 如果启用了GTID功能，则使用如下命令： mysql> CHANGE MASTER TO MASTER_HOST='master.magedu.com', MASTER_USER='repluser', MASTER_PASSWORD='replpass', MASTER_AUTO_POSITION=1; 没启用GTID，需要使用如下命令： slave> CHANGE MASTER TO MASTER_HOST='172.16.100.6', -> MASTER_USER='repluser', -> MASTER_PASSWORD='replpass', -> MASTER_LOG_FILE='master-bin.000003', -> MASTER_LOG_POS=1174; 二、半同步复制 1、分别在主从节点上安装相关的插件 master> INSTALL PLUGIN rpl_semi_sync_master SONAME 'semisync_master.so'; slave> INSTALL PLUGIN rpl_semi_sync_slave SONAME 'semisync_slave.so'; 2、启用半同步复制 在master上的配置文件中，添加 rpl_semi_sync_master_enabled=ON 在至少一个slave节点的配置文件中添加 rpl_semi_sync_slave_enabled=ON 而后重新启动mysql服务即可生效。 或者，也可以mysql服务上动态启动其相关功能： master> SET GLOBAL rpl_semi_sync_master_enabled = ON; slave> SET GLOBAL rpl_semi_sync_slave_enabled = ON; slave> STOP SLAVE IO_THREAD; START SLAVE IO_THREAD; 3、确认半同步功能已经启用 master> CREATE DATABASE magedudb; master> SHOW STATUS LIKE 'Rpl_semi_sync_master_yes_tx'; slave> SHOW DATABASES; 三、MySQL Proxy 1、源码安装时，MySQL proxy的依赖关系： libevent 1.x or higher (1.3b or later is preferred). lua 5.1.x or higher. glib2 2.6.0 or higher. pkg-config. libtool 1.5 or higher. MySQL 5.0.x or higher developer files. 2、安装 # tar zxf mysql-proxy-0.8.2.tar.gz # cd mysql-proxy-0.8.2 # ./configure # make # make check 如果管理员有密码，上面的步骤则需要使用如下格式进行： # MYSQL_PASSWORD=root_pwd make check # make install 默认情况下， mysql-proxy安装在/usr/local/sbin/mysql-proxy，而Lua示例脚本安装在/usr/local/share目录中。 3、配置指令 mysql proxy的各配置参数请参见官方文档，http://dev.mysql.com/doc/refman/5.6/en/mysql-proxy-configuration.html 使用rpm包在rhel6上安装mysql-proxy-0.8.2，其会提供配置文件及服务脚本，但没有提供读写分享的脚本。 /etc/sysconfig/mysql-proxy文件用于定义mysql-proxy的启动参数。 ADMIN_USER – the user for the proxy's admin interface. You can leave the default admin user. ADMIN_PASSWORD – the password for the admin user in clear text. Change the default password for better security. ADMIN_LUA_SCRIPT – the admin script in the Lua programming language. Without this script the admin interface cannot work. You can leave the default value. PROXY_USER – the system user under which the proxy will work. By default it is mysql-proxy, and it's safe to leave it as is. PROXY_OPTIONS – proxy options such as logging level, plugins, and Lua scripts to be loaded. 其中PROXY_OPTIONS是最常用的一个选项，用于定义mysql-proxy工作时的重要参数，例如： PROXY_OPTIONS="--daemon --log-level=info --log-use-syslog --plugins=proxy --plugins=admin --proxy-backend-addresses=192.168.1.102:3306 --proxy-read-only-backend-addresses=192.168.1.105:3306 --proxy-lua-script=/usr/lib/mysql-proxy/lua/proxy/rw-splitting.lua" 四、安装配置mysql-proxy: 4.1 下载所需要的版本，这里的系统平台为rhel6.4 32位系统，因此就以mysql-proxy-0.8.3-linux-glibc2.3-x86-32bit.tar.gz为例。 # tar xf mysql-proxy-0.8.3-linux-glibc2.3-x86-32bit.tar.gz -C /usr/local # cd /usr/local # ln -sv mysql-proxy-0.8.3-linux-glibc2.3-x86-32bit mysql-proxy 添加代理用户 # useradd mysql-proxy 4.2 为mysql-proxy提供SysV服务脚本，内容如下所示 #!/bin/bash # # mysql-proxy This script starts and stops the mysql-proxy daemon # # chkconfig: - 78 30 # processname: mysql-proxy # description: mysql-proxy is a proxy daemon for mysql # Source function library. . /etc/rc.d/init.d/functions prog="/usr/local/mysql-proxy/bin/mysql-proxy" # Source networking configuration. if [ -f /etc/sysconfig/network ]; then . /etc/sysconfig/network fi # Check that networking is up. [ ${NETWORKING} = "no" ] && exit 0 # Set default mysql-proxy configuration. ADMIN_USER="admin" ADMIN_PASSWD="admin" ADMIN_LUA_SCRIPT="/usr/local/mysql-proxy/share/doc/mysql-proxy/admin.lua" PROXY_OPTIONS="--daemon" PROXY_PID=/var/run/mysql-proxy.pid PROXY_USER="mysql-proxy" # Source mysql-proxy configuration. if [ -f /etc/sysconfig/mysql-proxy ]; then . /etc/sysconfig/mysql-proxy fi RETVAL=0 start() { echo -n $"Starting $prog: " daemon $prog $PROXY_OPTIONS --pid-file=$PROXY_PID --proxy-address="$PROXY_ADDRESS" --user=$PROXY_USER --admin-username="$ADMIN_USER" --admin-lua-script="$ADMIN_LUA_SCRIPT" --admin-password="$ADMIN_PASSWORD" RETVAL=$? echo if [ $RETVAL -eq 0 ]; then touch /var/lock/subsys/mysql-proxy fi } stop() { echo -n $"Stopping $prog: " killproc -p $PROXY_PID -d 3 $prog RETVAL=$? echo if [ $RETVAL -eq 0 ]; then rm -f /var/lock/subsys/mysql-proxy rm -f $PROXY_PID fi } # See how we were called. case "$1" in start) start ;; stop) stop ;; restart) stop start ;; condrestart|try-restart) if status -p $PROXY_PIDFILE $prog >&/dev/null; then stop start fi ;; status) status -p $PROXY_PID $prog ;; *) echo "Usage: $0 {start|stop|restart|reload|status|condrestart|try-restart}" RETVAL=1 ;; esac exit $RETVAL 将上述内容保存为/etc/rc.d/init.d/mysql-proxy，给予执行权限，而后加入到服务列表。 # chmod +x /etc/rc.d/init.d/mysql-proxy # chkconfig --add mysql-proxy 4.3 为服务脚本提供配置文件/etc/sysconfig/mysql-proxy，内容如下所示： # Options for mysql-proxy ADMIN_USER="admin" ADMIN_PASSWORD="admin" ADMIN_ADDRESS="" ADMIN_LUA_SCRIPT="/usr/local/mysql-proxy/share/doc/mysql-proxy/admin.lua" PROXY_ADDRESS="" PROXY_USER="mysql-proxy" PROXY_OPTIONS="--daemon --log-level=info --log-use-syslog" 其中最后一行，需要按实际场景进行修改，例如： PROXY_OPTIONS="--daemon --log-level=info --log-use-syslog --plugins=proxy --plugins=admin --proxy-backend-addresses=172.16.100.6:3306 --proxy-read-only-backend-addresses=172.16.100.7:3306 --proxy-lua-script=/usr/local/mysql-proxy/share/doc/mysql-proxy/rw-splitting.lua" 其中的proxy-backend-addresses选项和proxy-read-only-backend-addresses选项均可重复使用多次，以实现指定多个读写服务器或只读服务器。 4.4 mysql-proxy的配置选项 mysql-proxy的配置选项大致可分为帮助选项、管理选项、代理选项及应用程序选项几类，下面一起去介绍它们。 --help --help-admin --help-proxy --help-all ———— 以上四个选项均用于获取帮助信息； --proxy-address=host:port ———— 代理服务监听的地址和端口； --admin-address=host:port ———— 管理模块监听的地址和端口； --proxy-backend-addresses=host:port ———— 后端mysql服务器的地址和端口； --proxy-read-only-backend-addresses=host:port ———— 后端只读mysql服务器的地址和端口； --proxy-lua-script=file_name ———— 完成mysql代理功能的Lua脚本； --daemon ———— 以守护进程模式启动mysql-proxy； --keepalive ———— 在mysql-proxy崩溃时尝试重启之； --log-file=/path/to/log_file_name ———— 日志文件名称； --log-level=level ———— 日志级别； --log-use-syslog ———— 基于syslog记录日志； --plugins=plugin,.. ———— 在mysql-proxy启动时加载的插件； --user=user_name ———— 运行mysql-proxy进程的用户； --defaults-file=/path/to/conf_file_name ———— 默认使用的配置文件路径；其配置段使用[mysql-proxy]标识； --proxy-skip-profiling ———— 禁用profile； --pid-file=/path/to/pid_file_name ———— 进程文件名； 5、复制如下内容建立admin.lua文件，将其保存至/usr/local/mysql-proxy/share/doc/mysql-proxy/目录中。 --[[ $%BEGINLICENSE%$ Copyright (c) 2007, 2012, Oracle and/or its affiliates. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA $%ENDLICENSE%$ --]] function set_error(errmsg) proxy.response = { type = proxy.MYSQLD_PACKET_ERR, errmsg = errmsg or "error" } end function read_query(packet) if packet:byte() ~= proxy.COM_QUERY then set_error("[admin] we only handle text-based queries (COM_QUERY)") return proxy.PROXY_SEND_RESULT end local query = packet:sub(2) local rows = { } local fields = { } if query:lower() == "select * from backends" then fields = { { name = "backend_ndx", type = proxy.MYSQL_TYPE_LONG }, { name = "address", type = proxy.MYSQL_TYPE_STRING }, { name = "state", type = proxy.MYSQL_TYPE_STRING }, { name = "type", type = proxy.MYSQL_TYPE_STRING }, { name = "uuid", type = proxy.MYSQL_TYPE_STRING }, { name = "connected_clients", type = proxy.MYSQL_TYPE_LONG }, } for i = 1, #proxy.global.backends do local states = { "unknown", "up", "down" } local types = { "unknown", "rw", "ro" } local b = proxy.global.backends[i] rows[#rows + 1] = { i, b.dst.name, -- configured backend address states[b.state + 1], -- the C-id is pushed down starting at 0 types[b.type + 1], -- the C-id is pushed down starting at 0 b.uuid, -- the MySQL Server's UUID if it is managed b.connected_clients -- currently connected clients } end elseif query:lower() == "select * from help" then fields = { { name = "command", type = proxy.MYSQL_TYPE_STRING }, { name = "description", type = proxy.MYSQL_TYPE_STRING }, } rows[#rows + 1] = { "SELECT * FROM help", "shows this help" } rows[#rows + 1] = { "SELECT * FROM backends", "lists the backends and their state" } else set_error("use 'SELECT * FROM help' to see the supported commands") return proxy.PROXY_SEND_RESULT end proxy.response = { type = proxy.MYSQLD_PACKET_OK, resultset = { fields = fields, rows = rows } } return proxy.PROXY_SEND_RESULT end 6、测试 6.1 管理功能测试 # mysql -uadmin -padmin -h172.16.100.107 --port=4041 Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 1 Server version: 5.0.99-agent-admin Type 'help;' or '\h' for help. Type '\c' to clear the buffer. mysql> SELECT * FROM backends; +-------------+-------------------+-------+------+------+-------------------+ | backend_ndx | address | state | type | uuid | connected_clients | +-------------+-------------------+-------+------+------+-------------------+ | 1 | 172.16.100.6:3306 | up | rw | NULL | 0 | | 2 | 172.16.100.7:3306 | up | ro | NULL | 0 | +-------------+-------------------+-------+------+------+-------------------+ 2 rows in set (0.00 sec) 6.2 读写分离测试 # mysql -uroot -pmagedu.com -h172.16.100.107 --port=4040 下面的读写分享脚本是由mysql-proxy-0.8.3提供了，将其复制保存为/usr/lib/mysql-proxy/lua/proxy/rw-splitting.lua，就可以启动服务了。 --[[ $%BEGINLICENSE%$ Copyright (c) 2007, 2012, Oracle and/or its affiliates. All rights reserved. This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA $%ENDLICENSE%$ --]] ----- a flexible statement based load balancer with connection pooling -- -- * build a connection pool of min_idle_connections for each backend and maintain -- its size -- * -- local commands = require("proxy.commands") local tokenizer = require("proxy.tokenizer") local lb = require("proxy.balance") local auto_config = require("proxy.auto-config") --- config -- -- connection pool if not proxy.global.config.rwsplit then proxy.global.config.rwsplit = { min_idle_connections = 4, max_idle_connections = 8, is_debug = false } end --- -- read/write splitting sends all non-transactional SELECTs to the slaves -- -- is_in_transaction tracks the state of the transactions local is_in_transaction = false -- if this was a SELECT SQL_CALC_FOUND_ROWS ... stay on the same connections local is_in_select_calc_found_rows = false --- -- get a connection to a backend -- -- as long as we don't have enough connections in the pool, create new connections -- function connect_server() local is_debug = proxy.global.config.rwsplit.is_debug -- make sure that we connect to each backend at least ones to -- keep the connections to the servers alive -- -- on read_query we can switch the backends again to another backend if is_debug then print() print("[connect_server] " .. proxy.connection.client.src.name) end local rw_ndx = 0 -- init all backends for i = 1, #proxy.global.backends do local s = proxy.global.backends[i] local pool = s.pool -- we don't have a username yet, try to find a connections which is idling local cur_idle = pool.users[""].cur_idle_connections pool.min_idle_connections = proxy.global.config.rwsplit.min_idle_connections pool.max_idle_connections = proxy.global.config.rwsplit.max_idle_connections if is_debug then print(" [".. i .."].connected_clients = " .. s.connected_clients) print(" [".. i .."].pool.cur_idle = " .. cur_idle) print(" [".. i .."].pool.max_idle = " .. pool.max_idle_connections) print(" [".. i .."].pool.min_idle = " .. pool.min_idle_connections) print(" [".. i .."].type = " .. s.type) print(" [".. i .."].state = " .. s.state) end -- prefer connections to the master if s.type == proxy.BACKEND_TYPE_RW and s.state ~= proxy.BACKEND_STATE_DOWN and cur_idleproxy.connection.backend_ndx = i break elseif s.type == proxy.BACKEND_TYPE_RO and s.state ~= proxy.BACKEND_STATE_DOWN and cur_idleproxy.connection.backend_ndx = i break elseif s.type == proxy.BACKEND_TYPE_RW and s.state ~= proxy.BACKEND_STATE_DOWN and rw_ndx == 0 then rw_ndx = i end end if proxy.connection.backend_ndx == 0 then if is_debug then print(" [" .. rw_ndx .. "] taking master as default") end proxy.connection.backend_ndx = rw_ndx end -- pick a random backend -- -- we someone have to skip DOWN backends -- ok, did we got a backend ? if proxy.connection.server then if is_debug then print(" using pooled connection from: " .. proxy.connection.backend_ndx) end -- stay with it return proxy.PROXY_IGNORE_RESULT end if is_debug then print(" [" .. proxy.connection.backend_ndx .. "] idle-conns below min-idle") end -- open a new connection end --- -- put the successfully authed connection into the connection pool -- -- @param auth the context information for the auth -- -- auth.packet is the packet function read_auth_result( auth ) if is_debug then print("[read_auth_result] " .. proxy.connection.client.src.name) end if auth.packet:byte() == proxy.MYSQLD_PACKET_OK then -- auth was fine, disconnect from the server proxy.connection.backend_ndx = 0 elseif auth.packet:byte() == proxy.MYSQLD_PACKET_EOF then -- we received either a -- -- * MYSQLD_PACKET_ERR and the auth failed or -- * MYSQLD_PACKET_EOF which means a OLD PASSWORD (4.0) was sent print("(read_auth_result) ... not ok yet"); elseif auth.packet:byte() == proxy.MYSQLD_PACKET_ERR then -- auth failed end end --- -- read/write splitting function read_query( packet ) local is_debug = proxy.global.config.rwsplit.is_debug local cmd = commands.parse(packet) local c = proxy.connection.client local r = auto_config.handle(cmd) if r then return r end local tokens local norm_query -- looks like we have to forward this statement to a backend if is_debug then print("[read_query] " .. proxy.connection.client.src.name) print(" current backend = " .. proxy.connection.backend_ndx) print(" client default db = " .. c.default_db) print(" client username = " .. c.username) if cmd.type == proxy.COM_QUERY then print(" query = " .. cmd.query) end end if cmd.type == proxy.COM_QUIT then -- don't send COM_QUIT to the backend. We manage the connection -- in all aspects. proxy.response = { type = proxy.MYSQLD_PACKET_OK, } if is_debug then print(" (QUIT) current backend = " .. proxy.connection.backend_ndx) end return proxy.PROXY_SEND_RESULT end -- COM_BINLOG_DUMP packet can't be balanced -- -- so we must send it always to the master if cmd.type == proxy.COM_BINLOG_DUMP then -- if we don't have a backend selected, let's pick the master -- if proxy.connection.backend_ndx == 0 then proxy.connection.backend_ndx = lb.idle_failsafe_rw() end return end proxy.queries:append(1, packet, { resultset_is_needed = true }) -- read/write splitting -- -- send all non-transactional SELECTs to a slave if not is_in_transaction and cmd.type == proxy.COM_QUERY then tokens = tokens or assert(tokenizer.tokenize(cmd.query)) local stmt = tokenizer.first_stmt_token(tokens) if stmt.token_name == "TK_SQL_SELECT" then is_in_select_calc_found_rows = false local is_insert_id = false for i = 1, #tokens do local token = tokens[i] -- SQL_CALC_FOUND_ROWS + FOUND_ROWS() have to be executed -- on the same connection -- print("token: " .. token.token_name) -- print(" val: " .. token.text) if not is_in_select_calc_found_rows and token.token_name == "TK_SQL_SQL_CALC_FOUND_ROWS" then is_in_select_calc_found_rows = true elseif not is_insert_id and token.token_name == "TK_LITERAL" then local utext = token.text:upper() if utext == "LAST_INSERT_ID" or utext == "@@INSERT_ID" then is_insert_id = true end end -- we found the two special token, we can't find more if is_insert_id and is_in_select_calc_found_rows then break end end -- if we ask for the last-insert-id we have to ask it on the original -- connection if not is_insert_id then local backend_ndx = lb.idle_ro() if backend_ndx > 0 then proxy.connection.backend_ndx = backend_ndx end else print(" found a SELECT LAST_INSERT_ID(), staying on the same backend") end end end -- no backend selected yet, pick a master if proxy.connection.backend_ndx == 0 then -- we don't have a backend right now -- -- let's pick a master as a good default -- proxy.connection.backend_ndx = lb.idle_failsafe_rw() end -- by now we should have a backend -- -- in case the master is down, we have to close the client connections -- otherwise we can go on if proxy.connection.backend_ndx == 0 then return proxy.PROXY_SEND_QUERY end local s = proxy.connection.server -- if client and server db don't match, adjust the server-side -- -- skip it if we send a INIT_DB anyway if cmd.type ~= proxy.COM_INIT_DB and c.default_db and c.default_db ~= s.default_db then print(" server default db: " .. s.default_db) print(" client default db: " .. c.default_db) print(" syncronizing") proxy.queries:prepend(2, string.char(proxy.COM_INIT_DB) .. c.default_db, { resultset_is_needed = true }) end -- send to master if is_debug then if proxy.connection.backend_ndx > 0 then local b = proxy.global.backends[proxy.connection.backend_ndx] print(" sending to backend : " .. b.dst.name); print(" is_slave : " .. tostring(b.type == proxy.BACKEND_TYPE_RO)); print(" server default db: " .. s.default_db) print(" server username : " .. s.username) end print(" in_trans : " .. tostring(is_in_transaction)) print(" in_calc_found : " .. tostring(is_in_select_calc_found_rows)) print(" COM_QUERY : " .. tostring(cmd.type == proxy.COM_QUERY)) end return proxy.PROXY_SEND_QUERY end --- -- as long as we are in a transaction keep the connection -- otherwise release it so another client can use it function read_query_result( inj ) local is_debug = proxy.global.config.rwsplit.is_debug local res = assert(inj.resultset) local flags = res.flags if inj.id ~= 1 then -- ignore the result of the USE  -- the DB might not exist on the backend, what do do ? -- if inj.id == 2 then -- the injected INIT_DB failed as the slave doesn't have this DB -- or doesn't have permissions to read from it if res.query_status == proxy.MYSQLD_PACKET_ERR then proxy.queries:reset() proxy.response = { type = proxy.MYSQLD_PACKET_ERR, errmsg = "can't change DB ".. proxy.connection.client.default_db .. " to on slave " .. proxy.global.backends[proxy.connection.backend_ndx].dst.name } return proxy.PROXY_SEND_RESULT end end return proxy.PROXY_IGNORE_RESULT end is_in_transaction = flags.in_trans local have_last_insert_id = (res.insert_id and (res.insert_id > 0)) if not is_in_transaction and not is_in_select_calc_found_rows and not have_last_insert_id then -- release the backend proxy.connection.backend_ndx = 0 elseif is_debug then print("(read_query_result) staying on the same backend") print(" in_trans : " .. tostring(is_in_transaction)) print(" in_calc_found : " .. tostring(is_in_select_calc_found_rows)) print(" have_insert_id : " .. tostring(have_last_insert_id)) end end --- -- close the connections if we have enough connections in the pool -- -- @return nil - close connection -- IGNORE_RESULT - store connection in the pool function disconnect_client() local is_debug = proxy.global.config.rwsplit.is_debug if is_debug then print("[disconnect_client] " .. proxy.connection.client.src.name) end -- make sure we are disconnection from the connection -- to move the connection into the pool proxy.connection.backend_ndx = 0 end