private void migrateRefStream(final long refStreamId,
                                  final RefDataOffHeapStore feedSpecificStore) {
        LOGGER.info("Migrating ref stream {} from legacy ref store to feed specific store '{}'",
                refStreamId, feedSpecificStore);

        legacyRefDataStore.migrateRefStreams(refStreamId, feedSpecificStore);

        // Record the ID, so we don't have to migrate it again.
        migratedRefStreamIds.add(refStreamId);
    }
Get all ref stores keyed by feed name

@return Map of feedName => {@link RefDataOffHeapStore}
stroom-pipeline/src/main/java/stroom/pipeline/refdata/store/offheapstore/DelegatingRefDataOffHeapStore.java