test: refactor pummel/test-net-many-clients

* Use port 0 instead of `common.PORT`.
* Reduce `concurrent` from 100 to 50 and `connections_per_client` from 5
to 3. This is to avoid side effects from other tests. Prior to this
change, running this along with test-keep-alive would result in
failures on my local setup, apparently due to network throttling.
* Remove unnecessary `console.log()` and improve remaining
`console.log()` to provide clearer information.
PR-URL: #25485
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

Author: Trott

test/pummel/test-net-many-clients.js

@@ -20,30 +20,29 @@
 // USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 'use strict';
-constcommon=require('../common');
+require('../common');
 constassert=require('assert');
 constnet=require('net');
 
 // settings
 constbytes=1024*40;
-constconcurrency=100;
-constconnections_per_client=5;
+constconcurrency=50;
+constconnections_per_client=3;
 
 // measured
 lettotal_connections=0;
 
 constbody='C'.repeat(bytes);
 
 constserver=net.createServer(function(c){
-console.log('connected');
 total_connections++;
-console.log('#');
+console.log('connected',total_connections);
 c.write(body);
 c.end();
 });
 
-functionrunClient(callback){
-constclient=net.createConnection(common.PORT);
+functionrunClient(port,callback){
+constclient=net.createConnection(port);
 
 client.connections=0;
 
@@ -79,17 +78,17 @@ function runClient(callback) {
 assert.ok(!client.fd);
 
 if(this.connections<connections_per_client){
-this.connect(common.PORT);
+this.connect(port);
 }else{
 callback();
 }
 });
 }
 
-server.listen(common.PORT,function(){
+server.listen(0,function(){
 letfinished_clients=0;
 for(leti=0;i<concurrency;i++){
-runClient(function(){
+runClient(server.address().port,function(){
 if(++finished_clients===concurrency)server.close();
 });
 }