code: static long parseServerDurationFromFrame(final ByteBuf frame) {
          while(frame.readableBytes() > 0) {
              byte control = frame.readByte();
              byte id = (byte) (control & 0xF0);
              byte len = (byte) (control & 0x0F);
              if (id == FRAMING_EXTRAS_TRACING) {
                  return Math.round(Math.pow(frame.readUnsignedShort(), 1.74) / 2);
              } else {
                  frame.skipBytes(len);
              }
          }
          return 0;
      }
docs: Parses the server duration from the frame.
  
  It reads through the byte stream looking for the tracing frame and if
  found extracts the info. If a different frame is found it is just
  skipped.
  
  Per algorithm, the found server duration is round up/down using
  the {@link Math#round(float)} function and has microsecond
  precision.
  
  @param frame the extras frame to parse
  @return the extracted duration, 0 if not found.