Document wl_shm_pool creation costs
The cost of creating a wl_shm_pool
is currently underspecified. There are two possibilities:
- Creating a pool is very cheap, even if the pool is very large. This is the case for standard implementations backed by pagable virtual memory.
- Creating a pool is expensive, and may consume resources proportional to the size of the pool, even if most of the pool is never used. This is the case if the entire pool must be locked into memory.