在Erlang中发送大消息时，是否有引发竞争条件的风险? [英] Do you risk triggering race conditions when sending large messages in Erlang?

问题描述

在Erlang中，如果两个进程A和B正在同时向进程C发送消息.会不会有比赛条件?

In Erlang if two processes A and B are sending message to a process C simultaneously. Will there be a race condition?

• C！ A发送的{非常大的消息}
• C！ B发送的{非常大的消息}

• C ! {very large message} sent by A
• C ! {very large message} sent by B

C会收到来自A的完整消息，然后继续处理来自B的消息吗?还是C可能会同时接收A的消息块和B的消息块?

Will C receive the complete message from A and then proceed for the message from B? or is it that C is likely be going to receive chunks of A's message along with chunks of B's message?

推荐答案

消息接收是原子操作.

如果您对完成方法感兴趣，请阅读VM的源代码.如果简化一下，发送过程将执行以下步骤:

If you are interested how it is done, read the source code of VM. If I simplify it, the sending process is doing those steps:

1. 在发送过程中分配目标内存空间(称为环境).
2. 将消息复制到该存储空间
3. 对目标进程进行外部锁定
4. 将邮件链接到邮箱链接列表
5. 释放对目标进程的外部锁定

如您所见，复制是在关键部分之外(之前)完成的，并且关键部分的速度非常快.只是在玩弄很少的指针.

As you can see, copying is done outside (before) critical section and the critical section is pretty fast. It is just juggling with few pointers.

这篇关于在Erlang中发送大消息时，是否有引发竞争条件的风险?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！