AI代码解释 pg_ctl start-D~/12/data/
In the case of a logical replication slot, an output plugin for formatting the data returned by the replication slot is mandatory. • START_REPLICATION [SLOT slot_name][PHYSICAL] xxx/xxx [TIMELINE tli]:这告诉服务器在特定时间线的特定位置为给定复制槽启动 WAL 流。This tells the server to sta...
exec_replication_command(cmd_string = 0x1812418 "START_REPLICATION SLOT \"test_for_recvlogical\" LOGICAL 0/0") C++ (gdb) PostgresMain(argc = 1, argv = 0x18407b0, dbname = 0x1840720 "postgres", username = 0x1840708 "zjh") C++ (gdb) BackendRun(port = 0x183c740) C++ (gdb) BackendSta...
在物理复制中,Master节点会运行多个wal send进程;Standby节点会运行多个wal recv进程和startup进程,send是master发送wal日志的进程;recv进程是standby节点接受wal日志的进程,startup进程是standby节点apply wal日志的进程。 基于SQL的逻辑Replication:基本原理是应用端发出更改请求,master不断的产生日志,紧接着master的send...
walsender进程是用来发送WAL日志记录的,执行顺序如下:PostgresMain()->exec_replication_command()->StartReplication()->WalSndLoop()->XLogSendPhysical()walreceiver进程是用来接收WAL日志记录的,执行顺序如下:sigusr1_handler()->StartWalReceiver()->AuxiliaryProcessMain()->WalReceiverMain()->walrcv_receive()...
到了PostgreSQL9.2,一下命令是支持的: • IDENTIFY_SYSTEM • START_REPLICATION <position> • BASE_BACKUP °° [LABEL 'label'] °° [PROGRESS] °° [FAST] °° [WAL] °° [NOWAIT] 您所看到的是和pg_basebackup提供的作为命令行标志的协议等级。
START_REPLICATION[ SLOT slot_name] [ PHYSICAL] XXX/XXX[ TIMELINE tli] 无论是物理复制,还是逻辑复制,使用PostgreSQL的发布订阅或者pg_basebackup搭建流复制,都是通过复制协议与定义的消息进行交互(物理复制和逻辑复制数据流内容不同) 图- WAL数据流消息类型 ...
start-up:见上图5~6 catch-up:上图7 streaming:上图8 backup:因为备份发送整个数据库集群的文件,比如PG_basebackup工具 通过PG_stat_replication视图可以查看: testdb=# SELECT application_name,state FROM pg_stat_replication;application_name|state---+---standby1|streaming standby2|streaming pg_basebackup...
CREATEUSER'rep_username'REPLICATIONLOGINENCRYPTEDPASSWORD'rep_password'; 1. 第二步:配置流属性 接下来,使用 PostgreSQL 配置文件 ( postgresql.conf )配置流媒体属性,如下: 复制 wal_level=logicalwal_log_hints=onmax_wal_senders=8max_wal_size=1GBhot_standby=on ...
static bool libpqrcv_startstreaming(WalReceiverConn *conn, const WalRcvStreamOptions *options) { StringInfoData cmd; PGresult *res; initStringInfo(&cmd); /* Build the command. 构建命令 */ appendStringInfoString(&cmd, "START_REPLICATION"); ...