code: private void clearInternal(boolean clearMeta) {
          // Close all known segments
          for(int segId = 0, cnt = _segList.size(); segId < cnt; segId++) {
              Segment seg = _segList.get(segId);
              if(seg != null) {
                  try {
                      if(seg.getMode() == Segment.Mode.READ_WRITE) {
                          seg.force();
                      }
                      seg.close(false);
                  } catch (IOException e) {
                      _log.warn("failed to close segment " + seg.getSegmentId());
                  } finally {
                      _segList.set(segId, null);
                  }
              }
          }
          
          if(clearMeta) {
              try {
                  updateMeta();
              } catch (IOException e) {
                  _log.warn("failed to clear segment meta");
              }
          }
          
          _segList.clear();
          _recycleList.clear();
      }
docs: Clears this SegmentManager.
  
  @param clearMeta - whether to clear the segment meta file