如何使我的计数线程安全？

Question

I have a controller and its sole function is to increase a count in a model (ie foo_count ) and load a view.

Lets assume I have 2 web instances running. If 10 concurrent users were to hit this page/controller at the same time. Will my count be 10?

Will there be a race condition of some sort? Since they are concurrent hits, both web requests will load a copy of model Foobar , with foo_count equals to 0 via FoobarController .

This means they were both operating on their own copy of Foobar that wasn't aware of the change the other web instance was doing. Which also means, the count will unlikely be 10.

What are some ways to resolve this?

Answer 1

您应该使用内置记录锁定来避免出现竞争情况。