critical role

The coordination of processes and threads in Win32 is done by the synchronization mechanism, which is equivalent to a traffic light between threads. I. Synchronous and asynchronous As an example: PostMessage (), is to put the message in each other's message queue, and then regardless of 3,721, go back to the original call point to continue execution, which is asynchronous. SendMessage (), just like calling a generic function until the call function ends, will return to the origin, which is the s

Proactive-critical zone interrupt handling Hedgehog @http://blog.csdn.net/littlehedgehog The problem with a lot of code in the Linux kernel to deal with race condition (competitive conditions) is to add a switch interrupt instruction such as the CLI STI, which seems like a little worth mentioning. In the Wait_on_buffer function (shown in the following code), the switch interrupt is simply to avoid the competition condition and interrupt the

1. What is a critical section?A: The program that accesses critical resources in each process is called a critical section (a critical resource is a shared resource that only one process is allowed to use at a time). Only one process is allowed to enter the critical section

mutually exclusive into the critical area.function function: Off-switch key areaFunction Prototypes:void LeaveCriticalSection (lpcritical_sectionlpcriticalsection);Then set two key areas in the classic multithreading problem. One is when the main thread increments the child line program number, and the other is the mutually exclusive access output global resource for each child thread. See the code:[CPP]View PlainCopy #include #include #inc

A critical section is a way to implement thread synchronization. Windows provides 4 functions for the critical section (Initializecriticalsection,entercriticalsection,leavecriticalsection, DeleteCriticalSection), to use these functions, you must first have a critical section variable, Critical_section CS; The critical

Process Synchronization The critical-section problem(Critical area problem) Peterson ' s solution Concurrent access to shared data could result in data inconsistency. Maintaining data consistency requires mechanisms to ensure the orderly execution of cooperating processes. Suppose that we wanted to provide a solution to the consumer-producer problem this fills all the buffers. We can do so by have an inte

Control Methods for mutual exclusion of four processes or threads1. critical section: accesses public resources or code segments through multi-thread serialization, which is fast and suitable for controlling data access.2. mutex: designed to coordinate separate access to a shared resource.3. semaphore: designed to control a limited number of user resources.4. Event: it is used to notify the thread that some events have occurred and start subsequent ta

Tags: for Chrome browser ROM code database desc set Read Only scopeWindows Azure Platform Family of articles Catalog 　　 In the above blog, the author describes how to set the default role in RBAC. Here I will show you how to use a custom role. 　　 The main contents are: I. Understanding action and notaction in role Two. Through PowerShell, view the appropriate act

completed. Of course, chores that are not related to each other can work at the same time, and you can assume that John's farm has enough workers to do any number of tasks at the same time.Input/output formatInput format:Line 1th: An integer n, the number of chores that must be completed (32nd ~ n+1: A total of n rows, each line has a number of 1 spaces separated by an integer, respectively, said:* Work Sequence Number (1..N, in the input file is ordered);* The time required to complete the wor

Atitit. Database security critical sensitive data encryption storage solution1 . 1. the importance of encrypted storage 11 . 2. encryption algorithm used by AES 11 . 3. there will be some problems after data encryption. 11 . 3.1. One is statistics, such as the total amount of statistical funds. You cannot directly use the Database internal aggregate functions, such as SQL sum, to process the. 11 . 3.2. Another is to search by the amount, such as

This article supporting source code First, the preface I am studying the communication of threads, but there is so little information on this, there is no way I have to chew MSDN, but MSDN seems not very clear. So I wrote an example to look at the learning of multithreaded programming played a role in the casting of jade Brick. It's always easier to learn with an understandable example. I've been reviewing these algorithms recently, so I've written

Link: http://hi.baidu.com/reversefish/blog/item/7e2ddb1e4f11a11740341716.html Control Methods for mutual exclusion of four processes or threads1. critical section: accesses public resources or code segments through multi-thread serialization, which is fast and suitable for controlling data access.2. mutex: designed to coordinate separate access to a shared resource.3. semaphore: designed to control a limited number of user resources.4. Event: it is u

Control Methods for mutual exclusion of four processes or threads1. critical section: accesses public resources or code segments through multi-thread serialization, which is fast and suitable for controlling data access.2. mutex: designed to coordinate separate access to a shared resource.3. semaphore: designed to control a limited number of user resources.4. Event: it is used to notify the thread that some events have occurred and start subsequent ta

Control Methods for mutual exclusion of four processes or threads1. critical section: accesses public resources or code segments through multi-thread serialization, which is fast and suitable for controlling data access.2. mutex: designed to coordinate separate access to a shared resource.3. semaphore: designed to control a limited number of user resources.4. Event: it is used to notify the thread that some events have occurred and start subsequent ta

play a very important role in data tables, and an appropriate index can improve the performance of each table, and here's an article that explains how to create indexes and when to create them.15. No transaction mechanism is usedData integrity is important for web systems, and if data consistency is wrong, the entire system crashes and is difficult to repair. Reasonable use of database transaction mechanism will effectively solve this problem. For ex

Tags: size har algo speed ble problem is while postA solution to the problem of producer-consumerAtomic Operation (Atomic operation) requires that the operation be completed one time, without interruption in the middleRace Condition : The situation where several processes access and manipulate shared data concurrently (concurrency). The final value of the shared data depends upon which process finished last; (who finishes)In order to avoid race conditions, concurrency must be synchronizedCritica

Since the Google promotion of the new search rankings algorithm "Panda", many of the rankings of the site performance is not as big as before. Some travel websites reflect that "panda" algorithm makes their search results very bad, in the fight against "content farm" but also caused a very serious "accidental injury." Google says an important goal of the new algorithm is "to show more opportunities for sites that create original, high-quality content". Correspondingly, Google has adjusted its de

:1.8.0_91]View CodeThe reason is that a foreigner's blog has given the solution and the reason limited to English limited you can see for yourself 1. Address: https://github.com/spring-projects/spring-boot/issues/6447 2. Https://stackoverflow.com/questions/38958004/spring-boot-1-4-principal-must-not-be-null-exceptionThe translation is generally:When you have spring Boot actuator and spring security at the same time,trying to use SecurityContextHolder.getContext().getAuthentication() (or @Authent

Exchange 2007 Queue database, queue transaction log file exceeded critical value (threshold) resulting in an inability to accept mail solutions The day before yesterday, the Customer Exchange 2007 mail system suddenly went wrong. The specific performance is as follows: You can only send mail and cannot receive mail. Click Send and receive test in Outlook, only sending, no receiving status. Check the log to find the following tips: The Microsoft Ex

about 10 days, the premise is the space is very stable. 　　Third, the serious by K station If a long time site can not open, such as 20 days of web site space has not been restored, will be what the situation, of course, K Station, search engine that your site no longer used, directly deleted. This and good understanding, if a site is not used, after a period of time to search of course, a collection is not. We can not guarantee the absolute stability of the server, but the server after the