mongodb

https://www.mongodb.com/try/download/community

rpm -ivh  mongodb-org-server-6.0.5-1.el7.x86_64.rpm

mongod --dbpath /home/chengzhong/soft/mongo_data

检测是否安装成功

curl http://localhost:27017

1.冷拷数据:

cp -r mongo_data/ mongo_data_bak/

ps -ef|grep mongod

kill -9 14758 或 mongod --port=27017 --dbpath=/mongodb/data --shutdown

mongod --dbpath /home/chengzhong/soft/mongo_data_bak/

看启动日志:

{"t":{"$date":"2023-03-14T12:09:59.138+08:00"},"s":"I",  "c":"FTDC",     "id":20625,   "ctx":"initandlisten","msg":"Initializing full-time diagnostic data capture","attr":{"dataDirectory":"/home/chengzhong/soft/mongo_data_bak/diagnostic.data"}}
{"t":{"$date":"2023-03-14T12:09:59.144+08:00"},"s":"I",  "c":"REPL",     "id":6015317, "ctx":"initandlisten","msg":"Setting new configuration state","attr":{"newState":"ConfigReplicationDisabled","oldState":"ConfigPreStart"}}
{"t":{"$date":"2023-03-14T12:09:59.144+08:00"},"s":"I",  "c":"STORAGE",  "id":22262,   "ctx":"initandlisten","msg":"Timestamp monitor starting"}
{"t":{"$date":"2023-03-14T12:09:59.146+08:00"},"s":"I",  "c":"NETWORK",  "id":23015,   "ctx":"listener","msg":"Listening on","attr":{"address":"/tmp/mongodb-27017.sock"}}
{"t":{"$date":"2023-03-14T12:09:59.146+08:00"},"s":"I",  "c":"NETWORK",  "id":23015,   "ctx":"listener","msg":"Listening on","attr":{"address":"127.0.0.1"}}
{"t":{"$date":"2023-03-14T12:09:59.146+08:00"},"s":"I",  "c":"NETWORK",  "id":23016,   "ctx":"listener","msg":"Waiting for connections","attr":{"port":27017,"ssl":"off"}}
{"t":{"$date":"2023-03-14T12:10:00.066+08:00"},"s":"I",  "c":"FTDC",     "id":20631,   "ctx":"ftdc","msg":"Unclean full-time diagnostic data capture shutdown detected, found interim file, some metrics may have been lost","attr":{"error":{"code":0,"codeName":"OK"}}}
{"t":{"$date":"2023-03-14T12:10:08.414+08:00"},"s":"I",  "c":"NETWORK",  "id":22943,   "ctx":"listener","msg":"Connection accepted","attr":{"remote":"127.0.0.1:40592","uuid":"0a588590-cf8d-43a5-9aee-5407384abeb7","connectionId":1,"connectionCount":1}}

2.设置内存

mongod.conf

storage:
  dbPath: /data/mongodb/db
  journal:
    enabled: true
  engine: wiredTiger
    # 如下配置仅对 wiredTiger 引擎生效（3.0 以上版本）
  	wiredTiger:
  	  # wiredTiger 缓存工作集（working set）数据的内存大小，单位：GB
      # 此值决定了 wiredTiger 与 mmapv1 的内存模型不同，它可以限制 mongod 对内存的使用量，而 mmapv1 则不能（依赖于系统级的 mmap）。默认情况下，cacheSizeGB 的值为假定当前节点只部署一个 mongod 实例，此值的大小为物理内存的一半；如果当前节点部署了多个 mongod 进程，那么需要合理配置此值。如果 mongod 部署在虚拟容器中（比如，lxc，cgroups，Docker）等，它将不能使用整个系统的物理内存，则需要适当调整此值。默认值为物理内存的一半。
      engineConfig:
      	cacheSizeGB: 5
systemLog:
  destination: file
  logAppend: true
  path: /var/log/mongodb/mongod.log
net:
  port: 27017
  bindIp: 0.0.0.0
  maxIncomingConnections: 10000

3.安装注意事项

4.2.24.tgz包有较多命令文件，而新版本要么没有tgz包。如果安装server包，命令很少。要么有tgz包，解压后命令很少。

4.mongo大数据量，低配置，查询速度如何

数据量，1.2亿:

使用上索引，explain查询速度:

从上图看，只需要5毫秒

看机器配置,cpu2核,内存8G

实际查询时间,主要是网络时间与解析时间:

分片：

配置
./mongod --config /home/chengzhong/soft/mongo/conf/mongo1.conf
./mongod --config /home/chengzhong/soft/mongo/conf/mongo2.conf
./mongod --config /home/chengzhong/soft/mongo/conf/mongo3.conf



./mongo 192.168.1.7:28021
rs.initiate()
rs.add("192.168.1.7:28032")
rs.add({host:"192.168.1.7:28023",arbiterOnly:true})



mongos
./mongo 192.168.1.7:29000
use admin


db.runCommand({addShard:'ds1/192.168.1.7:28011,192.168.1.7:28012,192.168.1.7:28013'})
db.runCommand({addShard:'ds2/192.168.1.7:28021,192.168.1.7:28022,192.168.1.7:28023'})
db.runCommand({addShard:'ds3/192.168.1.7:28031,192.168.1.7:28032,192.168.1.7:28033'})

分片的库与表、片键
db.runCommand({enablesharding:'test'})
db.runCommand({shardcollection: 'test.col_student',key: {name: 1}})
db.runCommand({shardcollection: 'test.col_score',key: {_id: "hashed"}})