code: protected DataStore<byte[], byte[]> createDataStore(File homeDir, int initialCapacity) throws Exception {
          StoreConfig config = new StoreConfig(homeDir, initialCapacity);
          config.setSegmentFactory(new MemorySegmentFactory());
          config.setSegmentFileSizeMB(64);
          
          return StoreFactory.createStaticDataStore(config);
      }
docs: Creates a DataStore instance.
  <p>
  Subclasses can override this method to provide a specific DataStore implementation
  such as DynamicDataStore and IndexedDataStore or provide a specific SegmentFactory
  such as ChannelSegmentFactory, MappedSegmentFactory and WriteBufferSegment.