网站广告连接如何做,做网站的图片分类,海沧做网站,中英网站开发系统分布式锁的用法公司框架新增功能分布式锁#xff1a;锁的性能之王#xff1a;缓存 Zookeeper 数据库锁的实现实现原理#xff1a;核心采用StackExchange.Redis的LockTake方法实现。支持同步获取锁#xff0c;或者等待直到超时获取锁。/// summary///… 系统分布式锁的用法公司框架新增功能分布式锁锁的性能之王缓存 Zookeeper 数据库锁的实现实现原理核心采用StackExchange.Redis的LockTake方法实现。支持同步获取锁或者等待直到超时获取锁。/// summary/// 分布式锁提供全局分布式锁支持以resource redis为基础/// 这个锁只能通过RpcContext来获取通过自己手动释放/// /summarypublic sealed class DistributedLock{private static readonly TimeSpan DefaultAbandonmentCheckFrequency TimeSpan.FromSeconds(2);public readonly string lockName;private readonly string lockValue;private readonly int checkTimeSpan 50; //msprivate readonly int autoDelete;private DistributedLock(){}/// summary/// /// /summary/// param namelockName/param/// param nameautoDelete自动删除ms,默认 60s/param/// param namecheckTimeSpan如果不能获取锁重复检查间隔:默认 50ms/paraminternal DistributedLock(string lockName, int autoDelete 60000,int checkTimeSpan 50){// note that just Global\ is not a valid nameif (string.IsNullOrEmpty(lockName))throw new ArgumentNullException(lockName不能为空);if (null ResourceCache.Instance)throw new Exception(ResourceCache 没有配置或无法连接);this.checkTimeSpan Math.Max(checkTimeSpan,1);this.autoDelete Math.Max(autoDelete,1);this.lockName lockName;this.lockValue lockName;}/// summary/// 获取锁/// /summary/// param nametimeout超时为null则尝试一次即返回/param/// returns获取锁成功?/returnsinternal bool Acquire(TimeSpan? timeout null){bool bLock false;var dtStart DateTime.Now.Ticks;while (!bLock){bLock TryAcquireOnce();if (timeout null){break;}if (!bLock){Thread.Sleep(this.checkTimeSpan);}var ts new TimeSpan(DateTime.Now.Ticks - dtStart);if (ts timeout){break;}}return bLock;}//此处采用框架上下文管理分布式事务锁的释放代码略。//public void Dispose()//{// LockManager.ReleaseLock(this);//}internal void Release(){try{var bRtn ResourceCache.Instance.LockRelease(this.lockName, this.lockValue);Trace.WriteLine($释放锁 {this.lockName}:{bRtn});}catch (Exception e){LogTextWriter.Write($释放锁失败系统自动超时释放:{this.lockName});}}/// summary/// 释放锁/// /summarypublic void ReleaseLock(){LockManager.ReleaseLock(this);}private bool TryAcquireOnce(){try{Trace.WriteLine(${Thread.CurrentThread.ManagedThreadId}:TryAcquireOnce);var lock ResourceCache.Instance.LockTake(this.lockName, this.lockValue, new TimeSpan(0, 0, 0, 0, this.autoDelete));return lock;}catch (Exception e){return false;}}}
锁的使用在当前上下文中获取一个分布式锁第一个获取锁的将执行依赖当前key一般为业务主键的完整业务流程包括多个微服务之间的调用和数据库的访问;后来者将无法获取锁根据返回的结果来判断是否进入流程如果返回的锁为null将不能执行下面的流程要么重试等待锁释放要么返回错误.锁的调用一般流程 var qtLockTryGetLock(lockKey);if(qtLocknull) { //提示不能同时执行操作return}else {//进行业务流程}//最后别忘了qtLock.ReleaseLock();
API 内的范例 code StatusCode.OK;//传入超时时间可以一直等待到超时过期var lockSaveReceipt this.Context.TryGetLock(${nameof(SaveReceipt)}.{valueArgs.ReceiptArgs.ReceiptId});if (lockSaveReceipt null){code PublicErrorCode.SaveReceiptByUsed.ToCode();return null;}try{//todo 业务操作1//todo 业务操作2//...}finally{lockSaveReceipt.ReleaseLock();}
