public void reduce(KeyWritable key, Iterable<BytesWritable> values, Context ctx)
throws IOException, InterruptedException {
for (BytesWritable value : values) {
long startTime = System.currentTimeMillis();
ctx.write(key, value);
long elapsedTime = System.currentTimeMillis() - startTime;
ctx.getCounter(Counters.ELAPSED_TIME_MS).increment(elapsedTime);
ctx.getCounter(Counters.NUM_CELLS).increment(1);
}
}
