kingbaseES坏块修复功能

1、自动坏块修复简介

主数据库访问系统表数据、索引、持久化用户表数据、索引时，从磁盘读取数据块至共享缓冲区，如果检测到坏块，自动从备节点获取坏块的副本，并修复坏块。

坏块修复相关参数

参数名称	默认值	参数描述
auto_bmr.auto_bmr_max_sess	5	设置自动坏块修复最大的会话数
auto_bmr.auto_bmr_req_timeout	60	设置自动修复坏块超时时间，超过时间则推出自动修复
auto_bmr.auto_bmr_sess_threshold	100	单个会话最大坏块数量阈值超过则不启动自动修复
auto_bmr.auto_bmr_sys_threshold	1024	系统最大坏块数量阈值超过则不启动自动修复
auto_bmr.enable_auto_bmr	on	是否开启自动坏块修复

开启坏块修复

首选需要创建坏块修复扩展

kingbase=# create extension auto_bmr; CREATE EXTENSION kingbase=# show auto_bmr.enable_auto_bmr; AUTO_BMR.ENABLE_AUTO_BMR

on (1 行记录)

可以看到创建扩展后，默认的bmr状态已经开启。

同时也要注意在自动坏块修复过程中是有上限的，通过auto_bmr.auto_bmr_req_timeout、auto_bmr.auto_bmr_sess_threshold、 auto_bmr.auto_bmr_sys_threshold

其中auto_bmr.auto_bmr_req_timeout控制坏块修复的超时时间

auto_bmr.auto_bmr_sess_threshold和auto_bmr.auto_bmr_sys_threshold控制会话和系统级别坏块修复的page数量的阈值

如果达到了数量限制我们可以使用

select reset_auto_bmr_sys_bad_blk();

reset_auto_bmr_sess_bad_blk()；

两个函数重置相关数量限制。

自动坏块修复实操步骤

检查集群状态

[kingbase@localhost bin]$ repmgr cluster show

ID | Name | Role | Status | Upstream | Location | Priority | Timeline | LSN_Lag | Connection string

----+-------+---------+-----------+----------+----------+----------+----------+---------+---------------------------------------------------------------------------

1 | node1 | primary | * running | | default | 100 | 3 | | host=192.168.56.101 user=esrep dbname=esrep port=54321 connect_timeout=10

2 | node2 | standby | running | node1 | default | 100 | 3 | 0 bytes | host=192.168.56.103 user=esrep dbname=esrep port=54321 connect_timeout=10

创建测试表 并插入数据

[kingbase@localhost bin]$ ksql -U system kingbase

ksql (V8.0)

输入 "help" 来获取帮助信息.

kingbase=# drop table t1;

DROP TABLE

kingbase=# create table t1 (id int,name varchar2(100));

CREATE TABLE

kingbase=# insert into t1 values(generate_series(1,100000),now());

INSERT 0 100000

查看该测试表对应物理文件

kingbase=# select * from sys_relation_filepath('t1');

sys_relation_filepath

base/12178/74951

执行sh sys_monitor.sh stop停止集群

[kingbase@localhost bin]$ sh sys_monitor.sh stop 2023-06-16 10:04:57 Ready to stop all DB ... Service process "node_export" was killed at process 4623 Service process "postgres_ex" was killed at process 4624 Service process "node_export" was killed at process 3588 Service process "postgres_ex" was killed at process 3589 2023-06-16 10:05:01 begin to stop repmgrd on "[192.168.56.101]". 2023-06-16 10:05:02 repmgrd on "[192.168.56.101]" stop success. 2023-06-16 10:05:02 begin to stop repmgrd on "[192.168.56.103]". 2023-06-16 10:05:02 repmgrd on "[192.168.56.103]" stop success. 2023-06-16 10:05:02 begin to stop DB on "[192.168.56.103]". 等待服务器进程关闭 .... 完成 服务器进程已经关闭 2023-06-16 10:05:03 DB on "[192.168.56.103]" stop success. 2023-06-16 10:05:03 begin to stop DB on "[192.168.56.101]". 等待服务器进程关闭 .... 完成 服务器进程已经关闭 2023-06-16 10:05:04 DB on "[192.168.56.101]" stop success. 2023-06-16 10:05:04 Done. [kingbase@localhost bin]$

集群停止成功后，使用dd命令构造两个坏块

[kingbase@localhost bin]$ dd bs=8192 count=2 seek=1 of=/data/V8cluster/base/12178/74944 if=./kingbase conv=notrunc 记录了2+0 的读入 记录了2+0 的写出 16384字节(16 kB)已复制，0.000178303 秒，91.9 MB/秒 [kingbase@localhost bin]$

执行 sh sys_monitor.sh start启动集群

连接数据库，查询表，此时由于存在坏块，查询失败，报错提示

kingbase=# select * from t1;

WARNING: page is invalid: base/12178/74944, blockNum: 1

WARNING: Exec get buffer page failed,errMsg:ERROR: function public.get_lsn_reached_page(integer, integer, integer, integer, integer, integer) does not exist

LINE 1: select public.get_lsn_reached_page(1663, 12178, 74944, 0, 1,...

^

HINT: No function matches the given name and argument types. You might need to add explicit type casts.

WARNING: repair invalid page: base/12178/74944, block: 1 failed.

ERROR: invalid page in block 1 of relation base/12178/74944

kingbase=#

连接数据库创建插件auto_bmr;

create extension auto_bmr ;

再次执行查询，会进行坏块自动修复，并返回查询结果

kingbase=# select * from t1;

WARNING: page is invalid: base/12178/74951, blockNum: 1

WARNING: repair invalid page:base/12178/74951, blockNum: 1 successfully.

WARNING: page verification failed, calculated checksum 57120 but expected 17157

WARNING: page is invalid: base/12178/74951, blockNum: 2

WARNING: repair invalid page:base/12178/74951, blockNum: 2 successfully.

id | name

--------+-------------------------------

1 | 2023-06-16 10:12:50.601743+08

2 | 2023-06-16 10:12:50.601743+08

3 | 2023-06-16 10:12:50.601743+08