原创地址:http://www.cnblogs.com/jfzhu/p/4009918.html 转载请注明出处   (一)为什么需要并发控制机制 并发控制机制是为了防止多个用户同时更改同一条数据,也可以防止一个用户在更改数据的同时造成另一个用户看到"过期"的数据.下面看一个例子就明白了. John和Marry有一个联合银行帐户,帐户的余额是$1000,John向帐户里存入了$500,Marry取走了$500,如果没有并发控制,John最后看到的余额是$1500,而Marry看到的帐户…

大家好,欢迎回到性能调优培训.今天标志着第5个月培训的开始,这个月我们会谈论SQL Server里的锁.阻塞和死锁(Locking, Blocking, and Deadlocking). SQL Server提供悲观和乐观并发控制模式,它们用来定义并发查询的执行.这期我会给你讲解悲观并发控制模式里各种隔离级别概况,下周我会进一步介绍自SQL Server 2005起引入的乐观隔离级别情况. 悲观隔离级别(Pessimistic Isolation Levels) 悲观隔离级别意味着读查询(SE…

Optimistic concurrency control https://en.wikipedia.org/wiki/Optimistic_concurrency_control Optimistic concurrency control (OCC) is a concurrency control method applied to transactional systems such as relational database management systems and softw…

Optimistic concurrency control https://en.wikipedia.org/wiki/Optimistic_concurrency_control Optimistic concurrency control (OCC) is a concurrency control method applied to transactional systems such as relational database management systems and softw…

http://getakka.net/docs/concepts/terminology Terminology and Concepts In this chapter we attempt to establish a common terminology to define a solid ground for communicating about concurrent, distributed systems which Akka.NET targets. Please note th…

Rob pike发表过一个有名的演讲<Concurrency is not parallelism>(https://blog.golang.org/concurrency-is-not-parallelism), 演讲胶片在talks.golang.org中可以找到(https://talks.golang.org/2012/waza.slide#1), 演讲视频地址 :https://vimeo.com/49718712 以下是根据视频转换的文本信息. if you looked at t…

Concurrency in Entity Framework: Entity Framework supports Optimistic Concurrency by default. In the optimistic concurrency, EF saves the entity to the database, assuming that the same data has not changed since the entity was loaded. If it determine…

Hive Concurrency Model Hive Concurrency Model Use Cases Turn Off Concurrency Debugging Configuration Locking in Hive Transactions Use Cases Concurrency support (http://issues.apache.org/jira/browse/HIVE-1293) is a must in databases and their use case…

http://www.codeproject.com/Articles/89858/WCF-Concurrency-Single-Multiple-and-Reentrant-and Introduction and goalIn this article, we will concentrate on WCF concurrency and throttling. We will first try to understand what is WCF concurrency and the t…

如果你想从头学习Jmeter,可以看看这个系列的文章哦 https://www.cnblogs.com/poloyy/category/1746599.html Concurrency Thread Group的介绍 Concurrency Thread Group提供了用于配置多个线程计划的简化方法 该线程组目的是为了保持并发水平,意味着如果并发线程不够,则在运行线程中启动额外的线程 和Standard Thread Group不同,它不会预先创建所有线程,因此不会使用额外的内存 对于上篇讲到…