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给您的 MongoDB 定期做个体检：MongoDB 诊断

news 2025/9/19 8:50:51

新钛云服已累计为您分享739篇技术干货

接下来的一些列文章会为大家介绍日常工作中常用的 NoSQL 产品 MongoDB。

主要涉及到：

MongoDB 的安装及基本使用

MongoDB 文档查询

MongoDB 复制集

MongoDB 分片集群的介绍及搭建

MongoDB 安全加密

MongoDB 诊断

我们会用六篇文章近五万字来阐述 MongoDB 运维相关的日常实战事宜。您当前看到的是系列文章的第六篇：《MongoDB 诊断》。

随着 MongoDB 的不断运行且数据量日益增多，就会不免产生一些问题。当问题出现时，该怎么办呢？我们会从以下几个方面进行探讨。

日志

当有个长期运行的 MongoDB 进程时，我们可能想自己写个脚本来定期轮转日志文件。其实不用，MongoDB 已经提供了 logrotate 命令来完成这个操作，可以直接从 shell 里启动使用：

use adminrs0:PRIMARY> db.runCommand({logRotate: 1})
{"ok" : 1,"$clusterTime" : {"clusterTime" : Timestamp(1679966896, 1),"signature" : {"hash" : BinData(0,"50vWhFp/59fAKwBbUQUDxApF/+g="),"keyId" : NumberLong("7173500260914823169")}},"operationTime" : Timestamp(1679966896, 1)
}

需要注意：logRotate 是区分大小写的。

或者可以向 Mongo 进程发送 SIGUSR1 信号：

$ kill -SIGUSR1 <mongo_pid>

诊断命令

MongoDB 包含了许多命令可以报告内部状态，这些命令背后都是监控 MongoDB。下面是一些常见命令的参考命令，希望对大家有所帮助：

全局服务器统计信息： db.serverStatus();
统计当前运行的操作： db.currentOp();
包含空闲的操作： db currentOp(true)
每个数据库的计数器和活动统计： db.runCommand({top: 1}) ;
查看当前数据库信息： db.stats()

我们接下来分别看一看上述这几个命令的输出。

全局服务器信息统计

该命令输出的信息非常详细，当 MongoDB 出现问题时，是一个不错的诊断命令。

rs0:PRIMARY> db.serverStatus()
{"host" : "mongo03.tyun.cn","version" : "4.4.15","process" : "mongod","pid" : NumberLong(14092),"uptime" : 18727504,"uptimeMillis" : NumberLong("18727504137"),"uptimeEstimate" : NumberLong(18727504),"localTime" : ISODate("2023-03-28T01:30:35.805Z"),"asserts" : {"regular" : 0,"warning" : 0,"msg" : 0,"user" : 1380727,"rollovers" : 0},"connections" : {"current" : 17,"available" : 51183,"totalCreated" : 3253,"active" : 7,"exhaustIsMaster" : 3,"exhaustHello" : 2,"awaitingTopologyChanges" : 176},"defaultRWConcern" : {"localUpdateWallClockTime" : ISODate("2022-08-23T07:25:32.995Z")},"tcmalloc" : {"pageheap_free_bytes" : 94162944,"pageheap_unmapped_bytes" : 349478912,"max_total_thread_cache_bytes" : 1024458752,"current_total_thread_cache_bytes" : 238198560,"total_free_bytes" : 637257904,"central_cache_free_bytes" : 397502736,"transfer_cache_free_bytes" : 1556608,"thread_cache_free_bytes" : 238198560,"aggressive_memory_decommit" : 0,"pageheap_committed_bytes" : NumberLong("3653197824"),"pageheap_scavenge_count" : 13297522,"pageheap_commit_count" : 14804116,"pageheap_total_commit_bytes" : NumberLong("60304102580224"),"pageheap_decommit_count" : 13297522,"pageheap_total_decommit_bytes" : NumberLong("60300449382400"),"pageheap_reserve_count" : 459,"pageheap_total_reserve_bytes" : NumberLong("4002676736"),"spinlock_total_delay_ns" : NumberLong("111430768421"),"release_rate" : 1,"formattedString" : "------------------------------------------------\nMALLOC:     2921777552 ( 2786.4 MiB) Bytes in use by application\nMALLOC: +     94162944 (   89.8 MiB) Bytes in page heap freelist\nMALLOC: +    397502736 (  379.1 MiB) Bytes in central cache freelist\nMALLOC: +      1556608 (    1.5 MiB) Bytes in transfer cache freelist\nMALLOC: +    238197984 (  227.2 MiB) Bytes in thread cache freelists\nMALLOC: +     24510464 (   23.4 MiB) Bytes in malloc metadata\nMALLOC:   ------------\nMALLOC: =   3677708288 ( 3507.3 MiB) Actual memory used (physical + swap)\nMALLOC: +    349478912 (  333.3 MiB) Bytes released to OS (aka unmapped)\nMALLOC:   ------------\nMALLOC: =   4027187200 ( 3840.6 MiB) Virtual address space used\nMALLOC:\nMALLOC:         265177              Spans in use\nMALLOC:             72              Thread heaps in use\nMALLOC:           4096              Tcmalloc page size\n------------------------------------------------\nCall ReleaseFreeMemory() to release freelist memory to the OS (via madvise()).\nBytes released to the OS take up virtual address space but no physical memory.\n"}},"trafficRecording" : {"running" : false},"transactions" : {"retriedCommandsCount" : NumberLong(0),"retriedStatementsCount" : NumberLong(0),"transactionsCollectionWriteCount" : NumberLong(0),"currentActive" : NumberLong(0),"currentInactive" : NumberLong(0),"currentOpen" : NumberLong(0),"totalAborted" : NumberLong(0),"totalCommitted" : NumberLong(0),"totalStarted" : NumberLong(0),"totalPrepared" : NumberLong(0),"totalPreparedThenCommitted" : NumberLong(0),"totalPreparedThenAborted" : NumberLong(0),"currentPrepared" : NumberLong(0)},"transportSecurity" : {"1.0" : NumberLong(0),"1.1" : NumberLong(0),"1.2" : NumberLong(0),"1.3" : NumberLong(0),"unknown" : NumberLong(0)},"twoPhaseCommitCoordinator" : {"totalCreated" : NumberLong(0),"totalStartedTwoPhaseCommit" : NumberLong(0),"totalAbortedTwoPhaseCommit" : NumberLong(0),"totalCommittedTwoPhaseCommit" : NumberLong(0),"currentInSteps" : {"writingParticipantList" : NumberLong(0),"waitingForVotes" : NumberLong(0),"writingDecision" : NumberLong(0),"waitingForDecisionAcks" : NumberLong(0),"deletingCoordinatorDoc" : NumberLong(0)}},"wiredTiger" : {"uri" : "statistics:","block-manager" : {"blocks pre-loaded" : 23,"blocks read" : 4268362,"blocks written" : 39421996,"bytes read" : 48401854464,"bytes read via memory map API" : 0,"bytes read via system call API" : 0,"bytes written" : 418967826432,"bytes written for checkpoint" : 305570754560,"bytes written via memory map API" : 0,"bytes written via system call API" : 0,"mapped blocks read" : 0,"mapped bytes read" : 0,"number of times the file was remapped because it changed size via fallocate or truncate" : 0,"number of times the region was remapped via write" : 0},"capacity" : {"background fsync file handles considered" : 0,"background fsync file handles synced" : 0,"background fsync time (msecs)" : 0,"bytes read" : 39614959616,"bytes written for checkpoint" : 239185165378,"bytes written for eviction" : 97795992160,"bytes written for log" : 157233860864,"bytes written total" : 494215018402,"threshold to call fsync" : 0,"time waiting due to total capacity (usecs)" : 0,"time waiting during checkpoint (usecs)" : 0,"time waiting during eviction (usecs)" : 0,"time waiting during logging (usecs)" : 0,"time waiting during read (usecs)" : 0},"checkpoint-cleanup" : {"pages added for eviction" : 81667,"pages removed" : 16946,"pages skipped during tree walk" : 3064011324,"pages visited" : 5381579176},"connection" : {"auto adjusting condition resets" : 6326104,"auto adjusting condition wait calls" : 121447994,"auto adjusting condition wait raced to update timeout and skipped updating" : 61,"detected system time went backwards" : 0,"files currently open" : 71,"hash bucket array size for data handles" : 512,"hash bucket array size general" : 512,"memory allocations" : 14030754494,"memory frees" : 14027269174,"memory re-allocations" : 161883962,"pthread mutex condition wait calls" : 314479507,"pthread mutex shared lock read-lock calls" : 12181240198,"pthread mutex shared lock write-lock calls" : 743154980,"total fsync I/Os" : 275579938,"total read I/Os" : 4582332,"total write I/Os" : 313739357},"mem" : {"bits" : 64,"resident" : 3423,"virtual" : 5564,"supported" : true},"metrics" : {"aggStageCounters" : {"$_internalInhibitOptimization" : NumberLong(0),"$_internalSplitPipeline" : NumberLong(0),"$addFields" : NumberLong(1),"$bucket" : NumberLong(0),"$bucketAuto" : NumberLong(0),"$changeStream" : NumberLong(0),"$collStats" : NumberLong(0),"$count" : NumberLong(0),"$currentOp" : NumberLong(0),"$documents" : NumberLong(0),"$facet" : NumberLong(0),"$geoNear" : NumberLong(0),"$graphLookup" : NumberLong(0),"$group" : NumberLong(0),"$indexStats" : NumberLong(0),"$limit" : NumberLong(0),"$listLocalSessions" : NumberLong(0),"$listSessions" : NumberLong(0),"$lookup" : NumberLong(0),"$match" : NumberLong(1),"$merge" : NumberLong(0),"$mergeCursors" : NumberLong(0),"$out" : NumberLong(0),"$planCacheStats" : NumberLong(0),"$project" : NumberLong(2),"$queue" : NumberLong(0),"$redact" : NumberLong(0),"$replaceRoot" : NumberLong(0),"$replaceWith" : NumberLong(0),"$sample" : NumberLong(0),"$set" : NumberLong(46126),"$skip" : NumberLong(0),"$sort" : NumberLong(1),"$sortByCount" : NumberLong(0),"$unionWith" : NumberLong(0),"$unset" : NumberLong(0),"$unwind" : NumberLong(0)},"commands" : {"<UNKNOWN>" : NumberLong(2),"_isSelf" : {"failed" : NumberLong(0),"total" : NumberLong(13)},"buildInfo" : {"failed" : NumberLong(0),"total" : NumberLong(690365)},"count" : {"failed" : NumberLong(0),"total" : NumberLong(6)},"delete" : {"failed" : NumberLong(0),"total" : NumberLong(48)},"endSessions" : {"failed" : NumberLong(0),"total" : NumberLong(134)},"find" : {"failed" : NumberLong(0),"total" : NumberLong(2142077)},"getCmdLineOpts" : {"failed" : NumberLong(0),"total" : NumberLong(1380235)},"getDiagnosticData" : {"failed" : NumberLong(0),"total" : NumberLong(2070345)},"getFreeMonitoringStatus" : {"failed" : NumberLong(0),"total" : NumberLong(5)},"getLastError" : {"failed" : NumberLong(0),"total" : NumberLong(101)},"getLog" : {"failed" : NumberLong(0),"total" : NumberLong(5)},"getMore" : {"failed" : NumberLong(1),"total" : NumberLong(465344562)},"getnonce" : {"failed" : NumberLong(0),"total" : NumberLong(2)},"hello" : {"failed" : NumberLong(268),"total" : NumberLong(1384888)},"insert" : {"failed" : NumberLong(0),"total" : NumberLong(1)},"isMaster" : {"failed" : NumberLong(2),"total" : NumberLong(7731521)},"killCursors" : {"failed" : NumberLong(0),"total" : NumberLong(5)},"listCollections" : {"failed" : NumberLong(0),"total" : NumberLong(10)},"listDatabases" : {"failed" : NumberLong(0),"total" : NumberLong(57515)},"listIndexes" : {"failed" : NumberLong(3),"total" : NumberLong(124851)},"logRotate" : {"failed" : NumberLong(0),"total" : NumberLong(1)},"ping" : {"failed" : NumberLong(0),"total" : NumberLong(4436308)},"replSetGetConfig" : {"failed" : NumberLong(0),"total" : NumberLong(2070345)},"replSetGetRBID" : {"failed" : NumberLong(0),"total" : NumberLong(6)},"replSetGetStatus" : {"failed" : NumberLong(0),"total" : NumberLong(690128)},"replSetHeartbeat" : {"failed" : NumberLong(0),"total" : NumberLong(17000850)},"replSetRequestVotes" : {"failed" : NumberLong(0),"total" : NumberLong(4)},"replSetUpdatePosition" : {"failed" : NumberLong(0),"total" : NumberLong(390211482)},"rolesInfo" : {"failed" : NumberLong(0),"total" : NumberLong(1)},"saslContinue" : {"failed" : NumberLong(6),"total" : NumberLong(62466)},"saslStart" : {"failed" : NumberLong(0),"total" : NumberLong(57875)},"serverStatus" : {"failed" : NumberLong(0),"total" : NumberLong(1)},"update" : {"arrayFilters" : NumberLong(0),"failed" : NumberLong(0),"pipeline" : NumberLong(23063),"total" : NumberLong(511271)},"usersInfo" : {"failed" : NumberLong(0),"total" : NumberLong(1)},"whatsmyuri" : {"failed" : NumberLong(0),"total" : NumberLong(5)}},"cursor" : {"timedOut" : NumberLong(0),"open" : {"noTimeout" : NumberLong(0),"pinned" : NumberLong(1),"total" : NumberLong(1)}},"document" : {"deleted" : NumberLong(0),"inserted" : NumberLong(1),"returned" : NumberLong(322743825),"updated" : NumberLong(522796)},"getLastError" : {"wtime" : {"num" : 11577,"totalMillis" : 37265},"wtimeouts" : NumberLong(1),"default" : {"unsatisfiable" : NumberLong(0),"wtimeouts" : NumberLong(0)}},"operation" : {"scanAndOrder" : NumberLong(15),"writeConflicts" : NumberLong(9825)},"query" : {"planCacheTotalSizeEstimateBytes" : NumberLong(0),"updateOneOpStyleBroadcastWithExactIDCount" : NumberLong(0),"multiPlanner" : {"classicCount" : NumberLong(0),"classicMicros" : NumberLong(0),"classicWorks" : NumberLong(0),"histograms" : {"classicMicros" : [{"lowerBound" : NumberLong(0),"count" : NumberLong(0)},{"lowerBound" : NumberLong(1024),"count" : NumberLong(0)},{"lowerBound" : NumberLong(4096),"count" : NumberLong(0)},{"lowerBound" : NumberLong(16384),"count" : NumberLong(0)},{"lowerBound" : NumberLong(65536),"count" : NumberLong(0)},{"lowerBound" : NumberLong(262144),"count" : NumberLong(0)},{"lowerBound" : NumberLong(1048576),"count" : NumberLong(0)},{"lowerBound" : NumberLong(4194304),"count" : NumberLong(0)},{"lowerBound" : NumberLong(16777216),"count" : NumberLong(0)},{"lowerBound" : NumberLong(67108864),"count" : NumberLong(0)},{"lowerBound" : NumberLong(268435456),"count" : NumberLong(0)},{"lowerBound" : NumberLong(1073741824),"count" : NumberLong(0)}],"classicNumPlans" : [{"lowerBound" : NumberLong(0),"count" : NumberLong(0)},{"lowerBound" : NumberLong(2),"count" : NumberLong(0)},{"lowerBound" : NumberLong(4),"count" : NumberLong(0)},{"lowerBound" : NumberLong(8),"count" : NumberLong(0)},{"lowerBound" : NumberLong(16),"count" : NumberLong(0)},{"lowerBound" : NumberLong(32),"count" : NumberLong(0)}],"classicWorks" : [{"lowerBound" : NumberLong(0),"count" : NumberLong(0)},{"lowerBound" : NumberLong(128),"count" : NumberLong(0)},{"lowerBound" : NumberLong(256),"count" : NumberLong(0)},{"lowerBound" : NumberLong(512),"count" : NumberLong(0)},{"lowerBound" : NumberLong(1024),"count" : NumberLong(0)},{"lowerBound" : NumberLong(2048),"count" : NumberLong(0)},{"lowerBound" : NumberLong(4096),"count" : NumberLong(0)},{"lowerBound" : NumberLong(8192),"count" : NumberLong(0)},{"lowerBound" : NumberLong(16384),"count" : NumberLong(0)},{"lowerBound" : NumberLong(32768),"count" : NumberLong(0)}]}}},"queryExecutor" : {"scanned" : NumberLong(1070392),"scannedObjects" : NumberLong(323266658),"collectionScans" : {"nonTailable" : NumberLong(1386454),"total" : NumberLong(1386461)}},"record" : {"moves" : NumberLong(0)},"repl" : {"executor" : {"pool" : {"inProgressCount" : 0},"queues" : {"networkInProgress" : 0,"sleepers" : 3},"unsignaledEvents" : 0,"shuttingDown" : false,"networkInterface" : "DEPRECATED: getDiagnosticString is deprecated in NetworkInterfaceTL"},"apply" : {"attemptsToBecomeSecondary" : NumberLong(19),"batchSize" : NumberLong(318318346),"batches" : {"num" : 278600198,"totalMillis" : 5795319},"ops" : NumberLong(318318943)},"buffer" : {"count" : NumberLong(0),"maxSizeBytes" : NumberLong(268435456),"sizeBytes" : NumberLong(0)},"initialSync" : {"completed" : NumberLong(0),"failedAttempts" : NumberLong(0),"failures" : NumberLong(0)},"network" : {"bytes" : NumberLong("57955381887"),"getmores" : {"num" : 364468339,"totalMillis" : 15110995960,"numEmptyBatches" : NumberLong(67943454)},"notPrimaryLegacyUnacknowledgedWrites" : NumberLong(0),"notPrimaryUnacknowledgedWrites" : NumberLong(0),"oplogGetMoresProcessed" : {"num" : 465344548,"totalMillis" : 200161},"ops" : NumberLong(318318349),"readersCreated" : NumberLong(5),"replSetUpdatePosition" : {"num" : NumberLong(455260555)}},"stateTransition" : {"lastStateTransition" : "stepUp","userOperationsKilled" : NumberLong(0),"userOperationsRunning" : NumberLong(5)},"syncSource" : {"numSelections" : NumberLong(28),"numTimesChoseDifferent" : NumberLong(3),"numTimesChoseSame" : NumberLong(0),"numTimesCouldNotFind" : NumberLong(25)}},"ttl" : {"deletedDocuments" : NumberLong(9),"passes" : NumberLong(312121)}},"ok" : 1,"$clusterTime" : {"clusterTime" : Timestamp(1679967033, 3),"signature" : {"hash" : BinData(0,"7p9I6mnYmAqWdGWHZuVRCfEIJtU="),"keyId" : NumberLong("7173500260914823169")}},"operationTime" : Timestamp(1679967033, 3)
}

统计当前运行的操作

rs0:PRIMARY> db.currentOp()
{"inprog" : [{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "OplogApplier-0","active" : true,"currentOpTime" : "2023-03-28T01:37:05.539+00:00","effectiveUsers" : [{"user" : "__system","db" : "local"}],"opid" : -935445419,"op" : "none","ns" : "","command" : {},"numYields" : 0,"locks" : {},"waitingForLock" : false,"lockStats" : {},"waitingForFlowControl" : false,"flowControlStats" : {}},{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "TimestampMonitor","active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","opid" : -935445412,"op" : "none","ns" : "","command" : {},"numYields" : 0,"waitingForLatch" : {"timestamp" : ISODate("2023-03-28T01:37:05.546Z"),"captureName" : "ServiceContext::_mutex"},"locks" : {},"waitingForLock" : false,"lockStats" : {},"waitingForFlowControl" : false,"flowControlStats" : {}},{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "ReplBatcher","active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","opid" : -935445421,"op" : "none","ns" : "","command" : {},"numYields" : 0,"locks" : {},"waitingForLock" : false,"lockStats" : {"FeatureCompatibilityVersion" : {"acquireCount" : {"r" : NumberLong(1)}},"ReplicationStateTransition" : {"acquireCount" : {"w" : NumberLong(1)}},"Global" : {"acquireCount" : {"r" : NumberLong(1)}}},"waitingForFlowControl" : false,"flowControlStats" : {}},{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "conn333","connectionId" : 333,"client" : "10.20.20.11:42734","clientMetadata" : {"driver" : {"name" : "NetworkInterfaceTL","version" : "4.4.15"},"os" : {"type" : "Linux","name" : "CentOS Linux release 7.9.2009 (Core)","architecture" : "x86_64","version" : "Kernel 3.10.0-1160.62.1.el7.x86_64"}},"active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","effectiveUsers" : [{"user" : "__system","db" : "local"}],"opid" : -935445430,"secs_running" : NumberLong(1),"microsecs_running" : NumberLong(1002908),"op" : "command","ns" : "admin.$cmd","command" : {"isMaster" : 1,"maxAwaitTimeMS" : NumberLong(10000),"topologyVersion" : {"processId" : ObjectId("630480eb8e13bda8cb16c7e9"),"counter" : NumberLong(28)},"internalClient" : {"minWireVersion" : 9,"maxWireVersion" : 9},"$db" : "admin"},"numYields" : 0,"waitingForLatch" : {"timestamp" : ISODate("2023-03-28T01:37:04.649Z"),"captureName" : "FutureResolution"},"locks" : {},"waitingForLock" : false,"lockStats" : {},"waitingForFlowControl" : false,"flowControlStats" : {}},{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "conn6901","connectionId" : 6901,"client" : "10.20.20.19:56616","appName" : "MongoDB Shell","clientMetadata" : {"application" : {"name" : "MongoDB Shell"},"driver" : {"name" : "MongoDB Internal Client","version" : "4.4.15"},"os" : {"type" : "Linux","name" : "CentOS Linux release 7.9.2009 (Core)","architecture" : "x86_64","version" : "Kernel 3.10.0-1160.62.1.el7.x86_64"}},"active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","effectiveUsers" : [{"user" : "root","db" : "admin"}],"opid" : -935445413,"lsid" : {"id" : UUID("5daca131-7d85-4e21-a44b-2b1ded973009"),"uid" : BinData(0,"Y5mrDaxi8gv8RmdTsQ+1j7fmkr7JUsabhNmXAheU0fg=")},"secs_running" : NumberLong(0),"microsecs_running" : NumberLong(22989),"op" : "command","ns" : "admin.$cmd.aggregate","command" : {"currentOp" : 1,"lsid" : {"id" : UUID("5daca131-7d85-4e21-a44b-2b1ded973009")},"$clusterTime" : {"clusterTime" : Timestamp(1679967416, 1),"signature" : {"hash" : BinData(0,"hZEpDTiaiD3Zna+djn4cNU7WLjE="),"keyId" : NumberLong("7173500260914823169")}},"$db" : "admin"},"numYields" : 0,"locks" : {},"waitingForLock" : false,"lockStats" : {},"waitingForFlowControl" : false,"flowControlStats" : {}},{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "OplogCapMaintainerThread-local.oplog.rs","active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","opid" : -964016203,"op" : "none","ns" : "","command" : {},"numYields" : 0,"locks" : {},"waitingForLock" : false,"lockStats" : {"FeatureCompatibilityVersion" : {"acquireCount" : {"w" : NumberLong(1)}},"ReplicationStateTransition" : {"acquireCount" : {"w" : NumberLong(1)}},"Global" : {"acquireCount" : {"w" : NumberLong(1)}}},"waitingForFlowControl" : false,"flowControlStats" : {}},{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "conn2762","connectionId" : 2762,"client" : "10.20.20.41:33548","appName" : "QAN-mongodb-profiler-/agent_id/549d2b38-caf8-44a4-9903-28f769a12e68","clientMetadata" : {"driver" : {"name" : "mongo-go-driver","version" : "v1.11.1"},"os" : {"type" : "linux","architecture" : "amd64"},"platform" : "go1.19.1","application" : {"name" : "QAN-mongodb-profiler-/agent_id/549d2b38-caf8-44a4-9903-28f769a12e68"}},"active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","opid" : -935445550,"secs_running" : NumberLong(7),"microsecs_running" : NumberLong(7041972),"op" : "command","ns" : "admin.$cmd","command" : {"hello" : 1,"helloOk" : true,"topologyVersion" : {"processId" : ObjectId("630480eb8e13bda8cb16c7e9"),"counter" : NumberLong(28)},"maxAwaitTimeMS" : NumberLong(10000),"$db" : "admin","$readPreference" : {"mode" : "primaryPreferred"}},"numYields" : 0,"waitingForLatch" : {"timestamp" : ISODate("2023-03-28T01:36:58.610Z"),"captureName" : "FutureResolution"},"locks" : {},"waitingForLock" : false,"lockStats" : {},"waitingForFlowControl" : false,"flowControlStats" : {}},{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "JournalFlusher","active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","opid" : -935445414,"op" : "none","ns" : "","command" : {},"numYields" : 0,"locks" : {},"waitingForLock" : false,"lockStats" : {},"waitingForFlowControl" : false,"flowControlStats" : {}},{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "conn332","connectionId" : 332,"client" : "10.20.20.11:42736","clientMetadata" : {"driver" : {"name" : "NetworkInterfaceTL","version" : "4.4.15"},"os" : {"type" : "Linux","name" : "CentOS Linux release 7.9.2009 (Core)","architecture" : "x86_64","version" : "Kernel 3.10.0-1160.62.1.el7.x86_64"}},"active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","effectiveUsers" : [{"user" : "__system","db" : "local"}],"opid" : -935445538,"secs_running" : NumberLong(6),"microsecs_running" : NumberLong(6388394),"op" : "command","ns" : "admin.$cmd","command" : {"isMaster" : 1,"maxAwaitTimeMS" : NumberLong(10000),"topologyVersion" : {"processId" : ObjectId("630480eb8e13bda8cb16c7e9"),"counter" : NumberLong(28)},"internalClient" : {"minWireVersion" : 9,"maxWireVersion" : 9},"$db" : "admin"},"numYields" : 0,"waitingForLatch" : {"timestamp" : ISODate("2023-03-28T01:36:59.264Z"),"captureName" : "FutureResolution"},"locks" : {},"waitingForLock" : false,"lockStats" : {},"waitingForFlowControl" : false,"flowControlStats" : {}},{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "NoopWriter","active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","opid" : -935445599,"op" : "none","ns" : "","command" : {},"numYields" : 0,"locks" : {},"waitingForLock" : false,"lockStats" : {},"waitingForFlowControl" : false,"flowControlStats" : {}},{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "conn326","connectionId" : 326,"client" : "10.20.20.11:42726","appName" : "OplogFetcher","clientMetadata" : {"application" : {"name" : "OplogFetcher"},"driver" : {"name" : "MongoDB Internal Client","version" : "4.4.15"},"os" : {"type" : "Linux","name" : "CentOS Linux release 7.9.2009 (Core)","architecture" : "x86_64","version" : "Kernel 3.10.0-1160.62.1.el7.x86_64"}},"active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","effectiveUsers" : [{"user" : "__system","db" : "local"}],"opid" : -935445493,"secs_running" : NumberLong(3),"microsecs_running" : NumberLong(3702937),"op" : "getmore","ns" : "local.oplog.rs","command" : {"getMore" : NumberLong("3869305470684881343"),"collection" : "oplog.rs","batchSize" : NumberLong(13981010),"maxTimeMS" : NumberLong(5000),"term" : NumberLong(3),"lastKnownCommittedOpTime" : {"ts" : Timestamp(1661570687, 1397),"t" : NumberLong(2)},"$db" : "local","$replData" : 1,"$oplogQueryData" : 1,"$readPreference" : {"mode" : "secondaryPreferred"},"$clusterTime" : {"clusterTime" : Timestamp(1661570687, 1399),"signature" : {"hash" : BinData(0,"AAAAAAAAAAAAAAAAAAAAAAAAAAA="),"keyId" : NumberLong(0)}}},"planSummary" : "COLLSCAN",{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "conn2764","connectionId" : 2764,"client" : "10.20.20.41:33552","appName" : "mongodb_exporter","clientMetadata" : {"driver" : {"name" : "mongo-go-driver","version" : "v1.10.3"},"os" : {"type" : "linux","architecture" : "amd64"},"platform" : "go1.19.1","application" : {"name" : "mongodb_exporter"}},"active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","opid" : -935445535,"secs_running" : NumberLong(6),"microsecs_running" : NumberLong(6117158),"op" : "command","ns" : "admin.$cmd","command" : {"hello" : 1,"helloOk" : true,"topologyVersion" : {"processId" : ObjectId("630480eb8e13bda8cb16c7e9"),"counter" : NumberLong(28)},"maxAwaitTimeMS" : NumberLong(10000),"$db" : "admin","$readPreference" : {"mode" : "primaryPreferred"}},"numYields" : 0,"waitingForLatch" : {"timestamp" : ISODate("2023-03-28T01:36:59.535Z"),"captureName" : "FutureResolution"},"locks" : {},"waitingForLock" : false,"lockStats" : {},"waitingForFlowControl" : false,"flowControlStats" : {}},{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "WTCheckpointThread","active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","opid" : -935445426,"op" : "none","ns" : "","command" : {},"numYields" : 0,"locks" : {},"waitingForLock" : false,"lockStats" : {},"waitingForFlowControl" : false,"flowControlStats" : {}},{"type" : "op","host" : "mongo03.tyun.cn:27017","desc" : "conn184","connectionId" : 184,"client" : "10.20.20.41:45032","clientMetadata" : {"driver" : {"name" : "NetworkInterfaceTL","version" : "4.4.15"},"os" : {"type" : "Linux","name" : "CentOS Linux release 7.9.2009 (Core)","architecture" : "x86_64","version" : "Kernel 3.10.0-1160.62.1.el7.x86_64"}},"active" : true,"currentOpTime" : "2023-03-28T01:37:05.552+00:00","effectiveUsers" : [{"user" : "__system","db" : "local"}],"opid" : -935445564,"secs_running" : NumberLong(7),"microsecs_running" : NumberLong(7951531),"op" : "command","ns" : "admin.$cmd","command" : {"isMaster" : 1,"maxAwaitTimeMS" : NumberLong(10000),"topologyVersion" : {"processId" : ObjectId("630480eb8e13bda8cb16c7e9"),"counter" : NumberLong(28)},"internalClient" : {"minWireVersion" : 9,"maxWireVersion" : 9},"$db" : "admin"},"numYields" : 0,"waitingForLatch" : {"timestamp" : ISODate("2023-03-28T01:36:57.701Z"),"captureName" : "FutureResolution"},"locks" : {},"waitingForLock" : false,"lockStats" : {},"waitingForFlowControl" : false,"flowControlStats" : {}}],"ok" : 1,"$clusterTime" : {"clusterTime" : Timestamp(1679967416, 1),"signature" : {"hash" : BinData(0,"hZEpDTiaiD3Zna+djn4cNU7WLjE="),"keyId" : NumberLong("7173500260914823169")}},"operationTime" : Timestamp(1679967416, 1)
}

查看当前数据库统计信息

该命令返回当前连接的数据库信息。如：查看 admin 数据库信息：

rs0:PRIMARY> db.stats()
{"db" : "admin","collections" : 4,"views" : 0,"objects" : 10,"avgObjSize" : 242.8,"dataSize" : 2428,"storageSize" : 131072,"indexes" : 6,"indexSize" : 188416,"totalSize" : 319488,"scaleFactor" : 1,"fsUsedSize" : 44225654784,"fsTotalSize" : 64174051328,"ok" : 1,"$clusterTime" : {"clusterTime" : Timestamp(1679967646, 1),"signature" : {"hash" : BinData(0,"G/+ynHN7GNtj09WoJaJ4TMXR/sc="),"keyId" : NumberLong("7173500260914823169")}},"operationTime" : Timestamp(1679967646, 1)
}

还可以查看其他数据库信息：

rs0:PRIMARY> show dbs
admin        0.000GB
config       0.000GB
local        3.794GB
mongoshake   0.000GB
signals      0.000GB
streams      0.000GB
test         6.814GB
ycsb        14.253GB
rs0:PRIMARY> use streams
switched to db streams
rs0:PRIMARY> db.stats()
{"db" : "streams","collections" : 2,"views" : 0,"objects" : 2,"avgObjSize" : 40,"dataSize" : 80,"storageSize" : 40960,"indexes" : 2,"indexSize" : 40960,"totalSize" : 81920,"scaleFactor" : 1,"fsUsedSize" : 44226154496,"fsTotalSize" : 64174051328,"ok" : 1,"$clusterTime" : {"clusterTime" : Timestamp(1679967836, 1),"signature" : {"hash" : BinData(0,"L0keGbNUzAlINUX7sbG9t2TzkAk="),"keyId" : NumberLong("7173500260914823169")}},"operationTime" : Timestamp(1679967836, 1)
}

mongostat

mongostat 是 db.currentOp() 及 db.serverStatus() 命令的外部工具。以下是一个演示：

[root@mongo01 ~]# mongostat --host mongo03.tyun.cn:27017 --authenticationDatabase admin -u root 5
Enter password:insert query update delete getmore command dirty  used flushes vsize   res qrw arw net_in net_out conn set repl                time*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.61k   56.7k   19 rs0  PRI Mar 28 01:46:02.077*0    *0     *0     *0       0     4|0  0.3% 78.8%       1 5.43G 3.34G 0|0 1|0  1.78k   56.7k   19 rs0  PRI Mar 28 01:46:07.074*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.61k   56.8k   19 rs0  PRI Mar 28 01:46:12.075*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.79k   56.6k   19 rs0  PRI Mar 28 01:46:17.075*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:46:22.075*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.74k   56.5k   19 rs0  PRI Mar 28 01:46:27.074*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:46:32.074*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.74k   56.5k   19 rs0  PRI Mar 28 01:46:37.074*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:46:42.074*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.74k   56.5k   19 rs0  PRI Mar 28 01:46:47.074
insert query update delete getmore command dirty  used flushes vsize   res qrw arw net_in net_out conn set repl                time*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:46:52.075*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.74k   56.5k   19 rs0  PRI Mar 28 01:46:57.074*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:47:02.074*0    *0     *0     *0       0     4|0  0.3% 78.8%       1 5.43G 3.34G 0|0 1|0  1.74k   56.5k   19 rs0  PRI Mar 28 01:47:07.074*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:47:12.075*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.79k   56.6k   19 rs0  PRI Mar 28 01:47:17.074*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:47:22.076*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.74k   56.5k   19 rs0  PRI Mar 28 01:47:27.074*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:47:32.075*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.74k   56.5k   19 rs0  PRI Mar 28 01:47:37.074
insert query update delete getmore command dirty  used flushes vsize   res qrw arw net_in net_out conn set repl                time*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:47:42.074*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.74k   56.5k   19 rs0  PRI Mar 28 01:47:47.073*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:47:52.075*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.74k   56.5k   19 rs0  PRI Mar 28 01:47:57.074*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:48:02.075*0    *0     *0     *0       0     4|0  0.3% 78.8%       1 5.43G 3.34G 0|0 1|0  1.74k   56.5k   19 rs0  PRI Mar 28 01:48:07.074*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:48:12.074*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.79k   56.6k   19 rs0  PRI Mar 28 01:48:17.074*0    *0     *0     *0       0     5|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.65k   56.9k   19 rs0  PRI Mar 28 01:48:22.075*0    *0     *0     *0       0     4|0  0.3% 78.8%       0 5.43G 3.34G 0|0 1|0  1.74k   56.5k   19 rs0  PRI Mar 28 01:48:27.074

mongotop

mongotop 是 db.runCommand({top: 1}) 命令的外部工具。以下是命令的演示：

[root@mongo01 ~]# mongotop --host mongo03.tyun.cn:27017 --authenticationDatabase admin -u root 5
Enter password:2023-03-28T01:50:12.279+0000    connected to: mongodb://mongo03.tyun.cn:27017/ns    total    read    write    2023-03-28T01:50:17Zlocal.oplog.rs      4ms     4ms      0ms                        admin.$cmd.aggregate      0ms     0ms      0ms                        admin.system.keys      0ms     0ms      0ms                        admin.system.profile      0ms     0ms      0ms                        admin.system.roles      0ms     0ms      0ms                        admin.system.users      0ms     0ms      0ms                        admin.system.version      0ms     0ms      0ms                        config.settings      0ms     0ms      0ms                        
config.system.indexBuilds      0ms     0ms      0ms                        config.system.profile      0ms     0ms      0ms                        ns    total    read    write    2023-03-28T01:50:22Zlocal.oplog.rs      4ms     4ms      0ms                        admin.$cmd.aggregate      0ms     0ms      0ms                        admin.system.keys      0ms     0ms      0ms                        admin.system.profile      0ms     0ms      0ms                        admin.system.roles      0ms     0ms      0ms                        admin.system.users      0ms     0ms      0ms                        admin.system.version      0ms     0ms      0ms                        config.settings      0ms     0ms      0ms                        
config.system.indexBuilds      0ms     0ms      0ms                        config.system.profile      0ms     0ms      0ms                        ns    total    read    write    2023-03-28T01:50:27Zlocal.oplog.rs      4ms     4ms      0ms                        admin.$cmd.aggregate      0ms     0ms      0ms                        admin.system.keys      0ms     0ms      0ms                        admin.system.profile      0ms     0ms      0ms                        admin.system.roles      0ms     0ms      0ms                        admin.system.users      0ms     0ms      0ms                        admin.system.version      0ms     0ms      0ms                        config.settings      0ms     0ms      0ms                        
config.system.indexBuilds      0ms     0ms      0ms                        config.system.profile      0ms     0ms      0ms                        ^C2023-03-28T01:50:28.048+0000    signal 'interrupt' received; forcefully terminating

监控

监控是少不了的，可以考虑从主机及服务监控两个方面来监控 MongoDB。

主机监控

MongoDB 所在主机的监控是不可缺少的。现在有很多成熟的监控工具，具体选用什么监控工具，可以按照自己的习惯来选择即可。

服务监控

服务监控更是不可缺少的。

另外，我们对某个实例进行压测时，看看服务可以承受多大的压力，具体瓶颈在哪里，通过监控趋势图可以看得一清二楚。如：

./bin/ycsb run mongodb -s \-P workloads/workloada \-p recordcount=1000000 -p operationcount=1000000 \-p readproportion=0.5 -p updateproportion=0.5 \-p requestdistribution=zipfian \-p mongodb.url="mongodb://root:root123@mongo03.tyun.cn:27017/admin?waitQueueMultiple=100" \-threads 500

在对数据库进行压测时，可以查看监控：

总结

上面我们介绍了一些列的诊断工具，可以帮助我们迅速地判断当前 MongoDB 的运行状态。通过这些诊断，就可以给 MongoDB 开出一个药方，使其更健康。

本系列文章到此结束，希望本系列文章对大家有所帮助。后续我们会有更多的话题，请大家继续关注。

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