long getOplogSize() {
    return crf.currSize;
  }
The current size of Oplog. It may be less than the actual Oplog file size ( in case of asynch
writing as it also takes into account data present in asynch buffers which will get flushed in
course of time o

@return long value indicating the current size of the oplog.
geode-core/src/main/java/org/apache/geode/internal/cache/OverflowOplog.java