##当前语句有没有在等待锁 false即为否 "waitingForLock" : false, //当前整个服务器 整个库 整个表的读锁数和写锁数 "lockStats" : { "Global" : { "acquireCount" : { "r" : NumberLong(56), "w" : NumberLong(56) } }, "Database" : { "acquireCount" : { "w" : NumberLong(56) } ...
const NamespaceStringOrUUID& nssOrUUID, LockMode mode, Date_t deadline = Date_t::max()); CollectionLock(CollectionLock&&); ~CollectionLock(); private: ResourceId _id; OperationContext* _opCtx; };
上图中,有三个Lock,分别为Lock1, Lock2, Lock3,Lock1当前持有Res1,在等待Res2, Lock2当前持有Res2,在等待Res3,Lock3 当前持有Res3,在等待Res1。很明显死锁了,但是如何将其转化为有向图,使得计算机能帮我们检测死锁呢。 我们从Lock1 Acquire Res2来看, 由于Res2被Lock2持有,所以Lock1 Acquire Res2 依赖...
mongodb.locks.database.acquirewaitcount.sharedpswaits/second在 Shared (S) 模式中,因为锁保持在冲突模式而使获取数据库锁类型(database lock type)需要等待的次数 mongodb.locks.database.timeacquiringmicros.exclusivepsfractions在 Exclusive (X) 模式下等待数据库锁类型(database lock type)采集的时间 ...
在MongoDB 中为了提高并发效率,提供了类似读写锁的模式,即共享锁(Shared, S)(读锁)以及排他锁(Exclusive, X)(写锁),同时,为了解决多层级资源之间的互斥关系,提高多层级资源请求的效率,还在此基础上提供了意向锁(Intent Lock)。即锁可以划分为4中类型: ...
在几个handler痉挛过程中进入了另外一个线程池的ListConnectionHolder.Acquire()方法中,希望能得到该池中的000000f7b853d480锁对象。 同时25号线程正在反向做这个操作,由于大家都是双重 lock,所以最终导致死锁的发生。 三:有几个需要解答的问题 1. 为什么会有两个线程池?
acquire(name){try{constlock=newLock({_id:name,acquirer:this._uuid,acquiredAt:newDate(),updatedAt:newDate()});awaitlock.save();returntrue;}catch(e){console.log('cannot acquire');returnfalse;}}// 获取锁, 每3s重试一次asynclock(name,retryInterval=3000){while(true){if(awaitthis.acquire(...
replicaSet=rsTest`;constinstance=awaitmongoose.connect(mongoConnectionString,mongooseOptions);returninstance; MongoError: Unable to acquire lock \'{6989642780905297871: Database, 72113753264216015}\' within a max lock request timeout of \'5ms\' milliseconds. at Connection.<anonymous> (/Users/markpoliv...
Instance DB Locks Time to Acquire Read lockThe time (in milliseconds) that is spent in waiting to acquire the read lock on the database. For MongoDB version 3.x, or later, the value is N/A (not applicable). The type is int. The unit is milliseconds. ...
Lock":{"totalTime":NumberLong("616300534000"),"currentQueue":{"total":0,"readers":0,"writers":0},"activeClients":{"total":9,"readers":0,"writers":0}},"locks":{"Global":{"acquireCount":{"r":NumberLong(1471174),"w":NumberLong(2920),"W":NumberLong(4)}},"Database":{"acquire...