Provides a way to heap-allocate values which are not immediately deallocated upon Dropping them, but
are instead added to a queue of objects to be dropped later e.g. by a dedicated cleanup thread.
Useful for performance-sensitive multithreaded applications. You can allocate and/or deallocate in a low-priority thread, while using the allocated values in a high-priority thread.
Does not require a global allocator or std. You can use any allocator via the standard allocator API.
Extremely low overhead - no extra allocations and only one extra memory word per allocated object. Other approaches tend to A) require extra allocations and B) require the use of a global allocator.
Currently depends on embassy_sync for CriticalSectionRawMutex (used to lock the cleanup queue),
but it should be pretty easy to make this library parametric over choice of mutex.
Compared to defer_drop, which provides a similar capability:
- This library is
no_std - This library works with custom allocators (not just
Global) - This solution requires no extra allocations (
defer_droprequires a second allocation when the reference is dropped) - This solution performs zero heap operations in the high-priority thread
- The only locking required in the high-priority thread is to briefly lock the cleanup queue, for a single intrusive linked-list insert