[HADOOP-15130] SocketIOWithTimeout async close idle selector

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Component/s: common
• Assignee: Unassigned
• Reporter: zhangshilong
• Created: 19/Dec/17 06:32
• Updated: 19/Dec/17 06:39

Description

I start 1000 thread for NM and 1000 thread for AM in fairscheduler pressure test, using Scheduler Load Simulator（SLS） tool.
In jstack log, I found SocketIOWithTimeout remove idle selectors after every select Operation.
That will block 1000+ threads when doing iterator .

        for(Iterator<SelectorInfo> it = pList.queue.iterator(); it.hasNext();) {
          SelectorInfo info = it.next();
          if (info.lastActivityTime > cutoff) {
            break;
          }
          it.remove();
          info.close();
        }