BlockSeekContext seekContext = new BlockSeekContext(getBlockAt(
block.getStartOffset(), false, true));
DFSReadProfilingData pData = DFSClient.getDFSReadProfilingData();
while (true) {
FSClientReadProfilingData cliData = null;
if (pData != null) {
cliData = new FSClientReadProfilingData();
pData.addDFSClientReadProfilingData(cliData);
cliData.startRead();
}
DNAddrPair retval = chooseDataNode(seekContext, ignored);
DatanodeInfo chosenNode = retval.info;