Server listening at address xxx.xxx.xxx.xx:3000
Change board to: evaviktoriya
Concurrent connections count: 72
Concurrent connections count: 101
Concurrent connections count: 140
Concurrent connections count: 173
Concurrent connections count: 209
Concurrent connections count: 232
Concurrent connections count: 259
Concurrent connections count: 291
Concurrent connections count: 308
Concurrent connections count: 335
Concurrent connections count: 358
Concurrent connections count: 370
Concurrent connections count: 391
Concurrent connections count: 404
Concurrent connections count: 412
Concurrent connections count: 429
Concurrent connections count: 452
Concurrent connections count: 465
Concurrent connections count: 477
Concurrent connections count: 502
Concurrent connections count: 509
Concurrent connections count: 506
Concurrent connections count: 520
Concurrent connections count: 506
.....
Concurrent connections count: 5015
node.js валит 1 ядро на 100%.

скрипт безобидный. Запускается через forever
Делал по статейке настройки http://www.jayway.com/2015/04/13/600k-conc...-using-node-js/
как они держат на таком же сервере 600к подключений? Чего я незнаю?