Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

No, it's the mutable shared state that is the problem. Lock contention is just downstream of the same problems as any other mutable shared state.

> patterns like RCU

RCU isn't mutable shared state! It's sharing immutable state! That's the whole paradigm.



What do you think the "update" part of RCU actually does?


RCU publishes a new pointer after Copying and Updating the copied state. It's not mutating in-place. You don't use it for frequent updates.

https://en.wikipedia.org/wiki/Read-copy-update#Name_and_over...


You may not use it for frequent updates; we do.

There is state.

It is shared state.

It is mutable state.

There are readers, who can see the shared state.

There are writers, who copy it, update it and push it back so that the new state is visible to everyone else.

I have no idea what your definition of mutable shared state might be if that doesn't fit it.




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: