kiosk lock

This chapter introduces the lock Acquisition Mechanism of "fair lock" (the fair lock in this article refers to the fair lock of mutex lock), including: for basic concepts, refer to the Code to obtain the fair lock (based on JDK1.7

When InnoDB determines whether a row lock is in conflict, in addition to the most basic is/ix/s/x lock collision judgment, InnoDB also subdivides the lock into the following seed types: Record Lock (RK)Record locks, lock only one row of index records Gap

The lock mechanism is an important feature of a database that is different from the file system and an effective way to manage concurrent access. MySQL locks include table-level locks, page-level locks, and row-level locks. Table-level locks are the most granular locks in MySQL. They are easy to implement and consume less resources. They are supported by most MySQL engines. The most commonly used MYISAM and INNODB support table-level locks. The

level to be completely isolated, a bit of concurrency ...). Therefore, SQL Server's default read commited is a good choice to strike a balance between isolation and concurrency. SQL Server passes the lock, just like a traffic light at a crossroads, to tell all concurrent connections that at the same time those resources can be read and those resources can be modified. As mentioned earlier, the query itself is not a gentleman, so it needs to be superv

A recently maintained network server encountered performance problems, so it made major changes to the original program framework. Most of the changes are the thread working mode and data transmission mode. The final result is to change the lock usage mode. After some improvement, we can basically achieve GMB Network Adapter working at full speed. In After the performance was up to standard, I was wondering if I could use a more lightweight

Pessimistic lock and optimistic lock in hibernate Locking)During the implementation of business logic, data access needs to be exclusive. For example, in the daily final computing process of the financial system, we want to process the data at a cut-off time point instead of the settlement process (which may be several seconds, or several hours), and the data changes again. At this point, we need to use som

The previous sections mainly talk about atomic operations. As for some problems or traps related to atomic operations, they will be explained in the final summary. Starting from this chapter, we will spend a small amount of time talking about the lock mechanism. In the previous chapter, we talked about the lock mechanism and some related concepts and design ideas for atomic operations. In the next article,

Web applications tend to face multi-user environments, where concurrent write control is almost a skill that every developer must master. This paper mainly introduces the principle and use of Yii2.0 optimistic lock and pessimistic lock, hoping to help everyone. In a concurrent environment, it is possible to have dirty reads (Dirty read), non-repeatable reads (unrepeatable read), Phantom reads (Phantom read

Note: This article is reproduced from http://www.hollischuang.com/archives/934As described in the lock mechanism of a database, the task of concurrency control in a database management system (DBMS) is to ensure that the same data in the database is accessed simultaneously without disrupting the isolation and uniformity of the transaction and the consistency of the database.Optimistic concurrency control (optimistic

Tags: lin is larger than the database system type features basic angle inconsistency sql92Overview compared to other databases, MySQL's locking mechanism is relatively simple, and its most notable feature is that different storage engines support different locking mechanisms. MySQL can be broadly categorized into the following 3 types of locks: Table-level Lock: Low overhead, lock fast, no deadlock