1. private boolean updateStorefiles(final List<StoreFile> sfs, final long snapshotId)
2. throws IOException{
3. return needsCompaction();
4. }

public boolean needsCompaction(final Collection<StoreFile> storeFiles,
    final List<StoreFile> filesCompacting) {
  int numCandidates = storeFiles.size() - filesCompacting.size();
 
  return numCandidates >= comConf.getMinFilesToCompact();
}

minFilesToCompact = Math.max(2, conf.getInt(HBASE_HSTORE_COMPACTION_MIN_KEY,
/*old name*/ conf.getInt("hbase.hstore.compactionThreshold", 3)));

public static final String HBASE_HSTORE_COMPACTION_MIN_KEY = "hbase.hstore.compaction.min"
 
;

1. //Cache flushing thread.
2. this.cacheFlusher = new MemStoreFlusher(conf, this);
3. //Compaction thread
4. this.compactSplitThread = new CompactSplitThread(this);
   1. //Background thread to check for compactions; needed if region has not gotten updates
5. //in a while.It will take care of not checking too frequently on store
   -by-store basis.
6. this.compactionChecker = new CompactionChecker(this, this.threadWakeFrequency, this);
7. this.periodicFlusher = new PeriodicMemstoreFlusher(this.threadWakeFrequency, this);

1. private List<CompactionRequest> requestCompactionInternal(final Region r, final String why,
2. int p,List<Pair<CompactionRequest,Store>> requests, boolean selectNow,User user)
3. throws IOException{
4. for(Store s : r.getStores()){
5. CompactionRequest cr = requestCompactionInternal(r, s, why, p, null, selectNow, user);
6. }
7. }