Why is this JeroMQ (ZeroMQ port) benchmark so slow? - benchmarking

Question

I would like to use this library I found, it's a pure java port (not a wrapper) of zeromq.
I am trying to test it and while it claims some good numbers, the test I am performing is giving rather poor results and it's even performed locally (client and serve on the same machine). I'm sure it's something I am doing wrong. It takes approx. 5 seconds to execute this 10.000 messages loop.
All I did is take the Hello world example and removed pause and sysouts. Here is the code:
The Server:
package guide;
import org.jeromq.ZMQ;
public class hwserver{
public static void main(String[] args) throws Exception{
// Prepare our context and socket
ZMQ.Context context = ZMQ.context(1);
ZMQ.Socket socket = context.socket(ZMQ.REP);
System.out.println("Binding hello world server");
socket.bind ("tcp://*:5555");
while (true) {
byte[] reply = socket.recv(0);
String requestString = "Hello" ;
byte[] request = requestString.getBytes();
socket.send(request, 0);
}
}
}
The Client:
package guide;
import org.jeromq.ZMQ;
public class hwclient{
public static void main(String[] args){
ZMQ.Context context = ZMQ.context(1);
ZMQ.Socket socket = context.socket(ZMQ.REQ);
socket.connect ("tcp://localhost:5555");
System.out.println("Connecting to hello world server");
long start = System.currentTimeMillis();
for(int request_nbr = 0; request_nbr != 10_000; request_nbr++) {
String requestString = "Hello" ;
byte[] request = requestString.getBytes();
socket.send(request, 0);
byte[] reply = socket.recv(0);
}
long end = System.currentTimeMillis();
System.out.println(end-start);
socket.close();
context.term();
}
}
Is is possible to fix this code and get some decent numbers?

Answer 1

You're doing round-trip request-reply, and this will be just as slow using the C++ libzmq. You will only get fast performance on JeroQM, ZeroMQ, or any I/O when you do streaming.
Round-tripping is slow due to how I/O and TCP work. On libzmq we can do about 20K messages/second using round-tripping, and 8M/sec using streaming. Streaming has additional optimizations like batching which you can't do with round-trip request-reply.
For a throughput performance test, send 10M messages from node 1 to node 2, then send back a single ACK when you get them. Time that on ZeroMQ and on JeroMQ, you should see around 3x difference in speed.

Answer 2

Please refer the throughput test between synchronous round-trip and asynchronous round-trip at
https://github.com/zeromq/jeromq/blob/master/src/test/java/guide/tripping.java
The asynchronous was x40 faster than the synchronous round-trip.
If you want to benchmark the full speed of jeromq, please run perf.LocalThr and perf.RemoteThr on your environment.