There are no buffers allocated for the sampler. This should only occur if the sampler has
never been used. Once we allocate buffers once, we never dealloc them.

The idle state for the sampler. We have buffers allocated, but we're not actively sampling
nor is there a user handle associated with us.

We have buffers allocated and the user has a handle to us and can start a session.

The session is in progress. We are taking samples and writing data.

We have a read in flight. If we get a destruction request, we need to delay destruction of
resources until the read as completed.

We requested a session teardown while were we reading. Once the read finishes, we'll clear the
buffers and become allocated.