Consider use of Polymorphic Memory Resources for memory management.

[thorstenhater]

Polymorphic Memory Resources (PMR) allows us to easily control the allocators behind: string, vector, map, and folks.
That is without incurring a new template argument. However, support is still a bit behind (GCC 9 and Clang 16).

Here's some ideas on why this helpful to us

• use a per-thread bump allocator for temporaries, these allocate by simply bumping a pointer and get freed in bulk by simply resetting the pointer to the start. As they are per-thread, no synchronisation is needed. This makes for an extremely fast memory manager.
  Use during the following phases:
  • initialization
  • one per epoch to cover sampling
• A per-thread slab allocator for persistent objects that never gets freed and can be backed by a bump allocator. Example: Cell instances, shared state backing memory.