At the moment, LSM just uses an incrementing chunk ID to generate the URI for each chunk and Bloom filter. If we made an interface for this, something like:

int generate_uri(..., int chunk_id, int level, int type, char *buf, size_t *len)

where type == WT_LSM_DATA || type == WT_LSM_BLOOM

Then applications could place Bloom filters and chunks in different places, or place different levels of the tree on different types of storage subsystem.