Mongodb tuning records

Mongostat will output the current mongodb running status regularly

Mongostat -h X.X.X.X :27017 -u root -p123456 -h: specify the IP address and port you can use --port to specify the port number. -u: if authentication is enabled, enter the user name -p: passwordCopy the code

Example output:

Important field explanations and concerns:

• Insert: The number of objects inserted into the database per second. If it is slave, the value preceded by * indicates the replication set operation
• Query: Indicates the number of query operations per second
• Update: indicates the number of update operations per second
• Delete: indicates the number of deletion operations per second
• Getmore: GetMore operands per second to query cursor
• Dirty: Cache percentage of dirty data bytes (WiredTiger engine only)
• Used: percentage of caches in use (WiredTiger engine only)
• Flushes :(only for the WiredTiger engine) flushes the number of checkpoint triggers in a polling interval. Generally 0, indirect 1. Flush is expensive and can cause problems if flushed frequently
• Vsize: indicates the virtual memory usage
• Res: Physical memory usage
• Arw: number of active clients performing read and write operations
• QRW: queue length for clients to read and write data from the mongodb instance
• Net_in: network incoming traffic of mongo instances
• Net_out: network outgoing traffic of mongo instance
• Conn: The recommended number of open connections is less than 5000

View logs:

Start by finding the logpath definition in the mongod. Conf file. Then view the log file in the corresponding path

To set the log level:

db.setLogLevel(<level>, <component>)
level int
 0 is the mongodb default log level 
-1 all level 
 1 to 5 include debug message
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Enable slow request:

Db. setProfilingLevel(level) -0 disable - 1 record slow SQL (default: >100ms) - 2 record all commands db.setProfilingLevel(1,10) enables slow query and records statements that exceed 10msCopy the code

View slow query:

db.system.profile.find({}}); Db.system.profile. find({millis: {$gt:5}}); Db.system.profile.find ().sort({$natrual: -1}).limit(3); db.system.profile.find().sort({$natrual: -1}). Db.system.profile.find ().sort({$natural:-1}).limit(1); View the latest record {"ts" : ISODate(" 2012-05-20T16:50:36.321z "), "info" : "query test.system.profile reslen:1219 nscanned:8 \nquery: { query: {}, orderby: { $natural: -1.0}} Nreturned :8 bytes:1203", "millis" : 0} -ts: timestamp -info: specific operation -millis: time, millisecondsCopy the code

Analyze the requests mongodb is executing:

db.currentOp();

{
        "desc" : "conn632530",
        "threadId" : "140298196924160",
        "connectionId" : 632530,
        "client" : "11.192.159.236:57052",
        "active" : true,
        "opid" : 1008837885,
        "secs_running" : 0,
        "microsecs_running" : NumberLong(70),
        "op" : "update",
        "ns" : "mygame.players",
        "query" : {
            "uid" : NumberLong(31577677)
        },
        "numYields" : 0,
        "locks" : {
            "Global" : "w",
            "Database" : "w",
            "Collection" : "w"
        },
        ....
}

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Key concerns