Transactional Cube processing and rollups

Hey SDNers:

I have a quesstion regarding the processing of transactional data into a transactional cube.

Scenario:

I have a processes writing data to the transactional bufeer table.

I have reached the limit (say 50K) in the buffer and the process goes to commit the request to the cube.

However, there is a rollup going on against the cube (this typically creates a lock to prevent writing to the cube).

So, what happens?

1) Does the process enqueue and wait for the lock to be released?

2) Does the process fail? And, if so, what happens to the data in the transactional buffer?

Thanks for your guidance.

Mitchell