[Sasasu]

PG has a special memory manage rule, named MemoryContext. All memory allocated in a context will disappear when it leaves that context. this means that you can safely not free memory, or your memory will be freed in unexpected places. this is a big conflict with the way rust manages memory. write extension in rust won't improve it much.

And in PG, there is a special method to create a process, creating threads is not possible because the logging system makes heavy use of setjmp().

[zasdffaa]

> creating threads is not possible because the logging system makes heavy use of setjmp().

Naive question from a non-c user, setjmp/longjmp just manipulate the stack and since each thread has its own execution stack, that should be completely safe ISTM - so why is it unsafe/impossible? I'm missing something.

[dfox]

The general issue is that it is not designed for multi threaded environment and there is bunch of global and frequently accessed state. One could probably comb through the entire codebase and make all that state thread-local, but the benefit probably does not outweight the amount of work.