drm lock

Analysis of multi-thread object lock and Class lock, analysis of multi-thread class lockI. Preface I originally wanted to talk about it in another article. I found it may be a little too long, so I 'd better open another blog post. For more information, see Java multi-thread programming core technology. evaluate this book-a large amount of code and a simple description. It is like reading a blog. However, t

Mysql Series Articles Home===============Tips: Before reading this article, it is best to read this article (MySQL lock mechanism-line lock) articles ~In the previous article, we saw that the InnoDB default row lock makes it possible to operate on different rows without interacting and blocking, which solves the problem of multiple transactions and concurrency. H

I changed the lock code today. When I used the lock code later, I remember that I entered the modified lock code. However, an error was prompted, and the default 12345 error was entered, after a few more attempts, the system is suddenly locked (only five attempts can be entered ). Finally, I found that I set a 6-digit password with a default password of 5

one.Does the reader find that ms_sql and Oracle handle concurrency control differently?Five, lockThe following table is a compatibility or conflict case for locks.Existing S U XRequestS y y NU Y N NX n n N Existing S U X Application S Y Y N U Y N N X N N N Oracle six, isolation level and lockSeven, attention. General proced

Spin Lock (Spinlock): The purpose of the lock is to protect shared resources and achieve thread synchronization. The spin lock distinguishes itself from other locks in that if a thread is not acquiring a lock, it will constantly ask whether the spin-lock-holding person relea

1. Introduction Delete Process Division search and update two stages. Lock the clustered index record in the search phase, referring to the previous article. The update phase deletes the clustered index record, then search the two-level index record, record the Garin lock on the level two index, without locking, and finally the delete label on the two-level index record. Mysql_delete:: //rr_quick->...-

class at the same time.6 The . Synchronized keyword cannot be inherited, that is, the method of the base class synchronized F () {} is not automatically synchronized F () {} in the inheriting class, but instead becomes F () {}. Inheriting a class requires that you explicitly specify one of its methods as the Synchronized method. 7. When a global object or class is locked, all objects of that class function.Class Lock ExampleTo

Tags: lock pos process Resources style-o lrzsz apt-get commandInstall the software under Ubuntu16.04, for example: sudo apt-get install Lrzsz when prompted:　　Unable to get lock/var/lib/dpkg/lock-open (11: Resource temporarily unavailable)Unable to lock the management directory (/var/lib/dpkg/), is there any other proce

SQL Server lock type (SQL) favorites1. holdlock: Keep the shared lock on the table until the entire transaction ends, instead of releasing the added lock immediately after the statement is executed.2. nolock: no shared or exclusive locks are added. When this option takes effect, uncommitted data or "dirty data" may be read. This option is only applicable to selec

It is well known that synchronized can be used to modify methods and blocks of code for classes or objects.When a code block is decorated, synchronized (object) acts on the object, constraining only that object.Synchronized (class) acts on a class, constraining all objects of the class.When modifying a method, the synchronized modifies the static method for the class. Used for objects when modifying non-static methods.Note Class and object locks are two different locks, and they do not have a sy

This article mainly introduces the MySQL row-level lock, table-level lock, page-level lock detailed introduction, while enumerating some examples, the need for friends can refer to the following Page level: Engine BDB. Table level: Engine MyISAM, understood to lock the entire table, can read at the same time, wri