code: public synchronized void markClean(UUID cfId, ReplayPosition context)
      {
          if (!cfDirty.containsKey(cfId))
              return;
          if (context.segment == id)
              markClean(cfId, context.position);
          else if (context.segment > id)
              markClean(cfId, Integer.MAX_VALUE);
      }
docs: Marks the ColumnFamily specified by cfId as clean for this log segment. If the
  given context argument is contained in this file, it will only mark the CF as
  clean if no newer writes have taken place.
  
  @param cfId    the column family ID that is now clean
  @param context the optional clean offset