read lock

[Switch] Details about three Mysql backups: bitsCN.com I. purpose of backup Disaster Recovery: recover and restore damaged dataDemand Change: data needs to be restored to a time before the change due to demand changesTest: test whether the new

1.Lock The Reentrantlock is the implementation class for the lock interface, which should be used with lock. If the lock lock is not occupied by another thread, the current thread can obtain a lock lock immediately. The same thread can call

I have read several multi-threaded things before. Today I have reviewed it, read the fourth lock of Java concurrent programming, and review the flow of thread status, as shown below:Lock-related entry points: Lock and condition. Lock is an interface

In addition to Spinlock, the Linux kernel also has a spin lock called arch_rwlock_t. Its header file is Qrwlock.h, contained in Spinlock.h, which is called "Queue read/write lock" in the header file. This lock implements a read-write lock using only

ArticleDirectory Read lock request Request write lock Reading and Writing locks Alternate If the server does not use up memory, CPU, or threads, the request still takes a long time to complete, it may be that the server waits

Use read/write locks After configuring the read/write lock attribute, You can initialize the read/write lock. Use the following functions to initialize or destroy the read/write lock, lock or unlock the read/write lock, or attempt to lock the

Xtrabackup Execution Process Perform operations on the database during full backupHttps://www.cnblogs.com/digdeep/p/4946230.html We can see that xtrabackup has two threads in total for full backup. Set session lock_wait_timeout =

The kernel provides several ways to prevent competitive conditions, and understanding the usage scenarios of these methods helps us to choose the appropriate synchronization method when writing kernel code.This ensures the security of critical

Objective In order to ensure consistent integrity of data, there is a locking mechanism in any database. The quality of locking mechanism should be directly thought of the concurrent processing ability and performance of a database system, so the

The locking mechanism used by the MyISAM storage engine is fully implemented by the table-level locking mechanism provided by MySQL. MySQL has two types of table-level locks: Write locks and read locks. For write locks, MySQL uses the following

First, the purpose of the backup Do disaster recovery: Restore and restore corrupted dataChange in demand: need to restore data to change before it changesTesting: Testing whether new features are available Second, backup needs to consider the

mysql| Reference | Reference manual | Chinese MySQL 4.1.0 chinese reference manual---dog (heart sail) Translate MySQL Reference Manual for version 4.1.0-alpha. 6.7 MySQL Transaction and locking command 6.7.1 begin/commit/rollback syntax By

the memory barrier, read-write spin lock and sequential lock of the lock mechanism in Linux kernelIn the previous blog post, I discussed the related content of atomic manipulation and spin locks, and this post will continue the discussion of locking

In linux low-level file programming, file locks are an important part of multi-user multi-task operating systems. When updating a file, you expect to use a mechanism to prevent both processes from simultaneously updating the file in the same region,

http://haohaoxuexi.iteye.com/blog/2119733Ehcache Support for concurrencyIn the case of high concurrency, when using the Ehcache cache, the data we read may be wrong due to concurrent reads and writes, and the data we write may be accidentally

What is a read-write lockIn peacetime, our common synchronized and reentrantlock are basically exclusive locks, which allow only one thread to access it at the same time, even if it is a read operation. The read-write lock maintains a pair of locks (

the main reference to the http://blog.csdn.net/anonymalias/article/details/9197641 (anonymalias column) A record lock is an extended type of read-write lock in thread synchronization and can be used to synchronize file reading and writing with a

I. Data type-related issues 1, varchar (N) How much space is occupied(1) The N in varchar (n) is the number of characters, not the number of bytes;(2) Character type (varchar text blob, etc.) space = character actual length + field length;(3) The

Understanding mysql locks (2) Table-level locks the MyISAM storage engine uses a locking mechanism completely implemented by the table-level locks provided by MySQL. Mysql has two types of table-level locks: write locks and read locks for write

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