Eliminating Synchronization-Related Atomic Operations with Biased Locking and Bulk Rebiasing http://www.oracle.com/technetwork/java/biasedlocking-oopsla2006-wp-149958.pdf https://blogs.oracle.com/dave/biased-locking-in-hotspot Quickly Reacquirable Lo…

http://stackoverflow.com/questions/8972034/eclipse-hangs-on-loading-workbench 解答一: In most cases, rm workspace/.metadata/.lock works for me. Make sure to start eclipse using ./eclipse -clean -refresh whatever you try. Thanks for teaching us mv .eclip…

LOCK TABLES对事务不安全,并且在试图锁定表之前隐式提交任何活动事务. UNLOCK TABLES只有在LOCK TABLES已经获取到表锁时,会隐式提交任何活动事务.对于下面的一组语句,UNLOCK TABLES释放了全局读锁,但是因为没有表锁,不会提交事务. FLUSH TABLES WITH READ LOCK; START TRANSACTION; SELECT ... ; UNLOCK TABLES; 开始一个事务(例如,START TRANSACTION)隐式地提交任何当前事…

Articles Locking in Microsoft SQL Server (Part 12 – Lock Escalation) http://dba.stackexchange.com/questions/12864/what-is-lock-escalation 2008 R2 Lock Escalation (Database Engine) ---Forward from Locking in Microsoft SQL Server (Part 12 – Lock Escala…

Yesterday my colleague asked me for help...She has two android phones , one is hTC and the other is samsung. One day she changed the pattern lock and later she forgot...she tried all possible combination but in vain.. I check her phones and find them…

Servlet容器有两个主要的模块,即连接器(connector)与容器(container),本文接下来创建一个连接器来增强前面文章中的应用程序的功能,以一种更优雅的方式来创建request对象和response对象;为了兼容Servlet 2.3和2.4,连接器这里创建的是javax.servlet.http.HttpServletRequest对象和javax.servlet.http.HttpServletResponse对象(servlet对象类型可以是实现javax.servlet.…

https://www.percona.com/blog/2013/02/01/implications-of-metadata-locking-changes-in-mysql-5-5/ implications of Metadata Locking Changes in MySQL 5.5 Ovais Tariq  | February 1, 2013 |  Posted In: Insight for DBAs, Insight for Developers, MySQL While m…

最近经常遇到mysql数据库死锁,郁闷死, show processlist; 时 Waiting for table metadata lock 能一直锁很久 下面有官网的一段话,可以理解下 http://dev.mysql.com/doc/refman/5.5/en/metadata-locking.html 8.10.4. Metadata Locking MySQL 5.5.3 and up uses metadata locking to manage access to object…

原文: http://dev.mysql.com/doc/refman/5.0/en/innodb-locking-reads.html In some circumstances, a consistent (nonlocking) read is not convenient and a locking read is required instead. InnoDB supports two types of locking reads: SELECT ... LOCK IN SHARE…

出现下图这个现象之前是在一张事务操作频繁地表上,执行了truncate操作. mysql.sock@(none)> select user,host,db,command,time,state,info from information_schema.processlist where user='root'\G; *************************** . row *************************** user: root host: localhost db…