boolean scheduleNextForCompaction(BlobStore store) {
    return compactionExecutor != null && compactionExecutor.scheduleNextForCompaction(store);
  }
Schedules the given {@code store} for compaction next.
@param store the {@link BlobStore} to compact.
@return {@code true} if the scheduling was successful. {@code false} if not.
ambry-store/src/main/java/com/github/ambry/store/CompactionManager.java