@Override
    public long getBytesReceived() {
      return 0;
    }
Creates an instance of PerfRestRequest.
@param restMethod the {@link RestMethod} desired.
@param usermetadata the usermetadata that needs to be stored with the blob.
@param chunk the data that will form each chunk of this request upto the size defined in {@code totalBlobSize}.
@param totalBlobSize the total size of the blob represented by this PerfRestRequest.
ambry-tools/src/main/java/com/github/ambry/tools/perf/rest/PerfNioServer.java