If a remove is the first operation for a given set of leaf nodes in the SIFS index it will not properly mark the size as free to the compactor. Normally this doesn't happen as a remove shouldn't be fired without the key being present (requires leaf nodes) or any other key.

We probably need to mark an index update as being from a remove so the index can know to ignore such operations and still update the compactor properly.

This can be seen by doing a simple remove on a fresh started cache with a SIFS store.