Frappe Bench not running error

When i start the bench it gave me following error. I am new to erpnext and linux so, I can’t understand what’s happening. It works fine few days before but now its not running.
here is what it shows

05:55:36 watch.1 | Wrote js/erpnext.min.js - 138.58 KB
05:55:36 watch.1 | Wrote js/item-dashboard.min.js - 8.19 KB
05:55:37 watch.1 | events.js:136
05:55:37 watch.1 | throw er; // Unhandled ‘error’ event
05:55:37 watch.1 | ^
05:55:37 watch.1 |
05:55:37 watch.1 | Error: watch /home/ubench/frappe-bench/apps/frappe/frappe/public/js/frappe/model/perm.js ENOSPC
05:55:37 watch.1 | at _errnoException (util.js:1031:13)
05:55:37 watch.1 | at FSWatcher.start (fs.js:1397:19)
05:55:37 watch.1 | at Object.fs.watch (fs.js:1423:11)
05:55:37 watch.1 | at createFsWatchInstance (/home/ubench/frappe-bench/node_modules/chokidar/lib/nodefs-handler.js:37:15)
05:55:37 watch.1 | at setFsWatchListener (/home/ubench/frappe-bench/node_modules/chokidar/lib/nodefs-handler.js:80:15)
05:55:37 watch.1 | at FSWatcher.NodeFsHandler._watchWithNodeFs (/home/ubench/frappe-bench/node_modules/chokidar/lib/nodefs-handler.js:228:14)
05:55:37 watch.1 | at FSWatcher.NodeFsHandler._handleFile (/home/ubench/frappe-bench/node_modules/chokidar/lib/nodefs-handler.js:255:21)
05:55:37 watch.1 | at FSWatcher. (/home/ubench/frappe-bench/node_modules/chokidar/lib/nodefs-handler.js:473:21)
05:55:37 watch.1 | at FSReqWrap.oncomplete (fs.js:167:5)
05:55:37 system | watch.1 stopped (rc=0)
05:55:37 system | sending SIGTERM to redis_socketio.1 (pid 2868)
05:55:37 system | sending SIGTERM to worker_long.1 (pid 2867)
05:55:37 system | sending SIGTERM to redis_queue.1 (pid 2875)
05:55:37 system | sending SIGTERM to web.1 (pid 2864)
05:55:37 system | sending SIGTERM to schedule.1 (pid 2885)
05:55:37 system | sending SIGTERM to worker_default.1 (pid 2872)
05:55:37 system | sending SIGTERM to socketio.1 (pid 2874)
05:55:37 system | sending SIGTERM to redis_cache.1 (pid 2893)
05:55:37 system | sending SIGTERM to worker_short.1 (pid 2890)
05:55:37 redis_socketio.1 | 2878:signal-handler (1513126537) Received SIGTERM scheduling shutdown…
05:55:37 redis_socketio.1 | 2878:M 13 Dec 05:55:37.728 # User requested shutdown…
05:55:37 redis_socketio.1 | 2878:M 13 Dec 05:55:37.728 # Redis is now ready to exit, bye bye…
05:55:37 system | redis_socketio.1 stopped (rc=-15)
05:55:37 worker_long.1 | 05:55:37 Warm shut down requested
05:55:37 redis_queue.1 | 2881:signal-handler (1513126537) Received SIGTERM scheduling shutdown…
05:55:37 redis_queue.1 | 2881:M 13 Dec 05:55:37.728 # User requested shutdown…
05:55:37 redis_queue.1 | 2881:M 13 Dec 05:55:37.729 # Redis is now ready to exit, bye bye…
05:55:37 system | redis_queue.1 stopped (rc=-15)
05:55:37 worker_short.1 | Traceback (most recent call last):
05:55:37 worker_short.1 | File “/usr/lib/python2.7/runpy.py”, line 174, in _run_module_as_main
05:55:37 worker_short.1 | “main”, fname, loader, pkg_name)
05:55:37 worker_short.1 | File “/usr/lib/python2.7/runpy.py”, line 72, in _run_code
05:55:37 worker_short.1 | exec code in run_globals
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/apps/frappe/frappe/utils/bench_helper.py”, line 94, in
05:55:37 worker_short.1 | main()
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/apps/frappe/frappe/utils/bench_helper.py”, line 18, in main
05:55:37 worker_short.1 | click.Group(commands=commands)(prog_name=‘bench’)
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/click/core.py”, line 722, in call
05:55:37 worker_short.1 | return self.main(*args, **kwargs)
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/click/core.py”, line 697, in main
05:55:37 worker_short.1 | rv = self.invoke(ctx)
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/click/core.py”, line 1066, in invoke
05:55:37 worker_short.1 | return _process_result(sub_ctx.command.invoke(sub_ctx))
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/click/core.py”, line 1066, in invoke
05:55:37 worker_short.1 | return _process_result(sub_ctx.command.invoke(sub_ctx))
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/click/core.py”, line 895, in invoke
05:55:37 worker_short.1 | return ctx.invoke(self.callback, **ctx.params)
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/click/core.py”, line 535, in invoke
05:55:37 worker_short.1 | return callback(*args, **kwargs)
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/apps/frappe/frappe/commands/scheduler.py”, line 157, in start_worker
05:55:37 worker_short.1 | start_worker(queue)
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/apps/frappe/frappe/utils/background_jobs.py”, line 124, in start_worker
05:55:37 worker_short.1 | Worker(queues, name=get_worker_name(queue)).work()
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/rq/worker.py”, line 483, in work
05:55:37 worker_short.1 | self.register_death()
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/rq/worker.py”, line 282, in register_death
05:55:37 worker_short.1 | p.execute()
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/redis/client.py”, line 2894, in execute
05:55:37 worker_short.1 | return execute(conn, stack, raise_on_error)
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/redis/client.py”, line 2749, in _execute_transaction
05:55:37 worker_short.1 | connection.send_packed_command(all_cmds)
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/redis/connection.py”, line 585, in send_packed_command
05:55:37 worker_short.1 | self.connect()
05:55:37 worker_short.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/redis/connection.py”, line 489, in connect
05:55:37 worker_short.1 | raise ConnectionError(self._error_message(e))
05:55:37 worker_short.1 | redis.exceptions.ConnectionError: Error 111 connecting to localhost:11000. Connection refused.
05:55:37 worker_default.1 | Traceback (most recent call last):
05:55:37 worker_default.1 | File “/usr/lib/python2.7/runpy.py”, line 174, in _run_module_as_main
05:55:37 worker_default.1 | “main”, fname, loader, pkg_name)
05:55:37 worker_default.1 | File “/usr/lib/python2.7/runpy.py”, line 72, in _run_code
05:55:37 worker_default.1 | exec code in run_globals
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/apps/frappe/frappe/utils/bench_helper.py”, line 94, in
05:55:37 worker_default.1 | main()
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/apps/frappe/frappe/utils/bench_helper.py”, line 18, in main
05:55:37 worker_default.1 | click.Group(commands=commands)(prog_name=‘bench’)
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/click/core.py”, line 722, in call
05:55:37 worker_default.1 | return self.main(*args, **kwargs)
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/click/core.py”, line 697, in main
05:55:37 worker_default.1 | rv = self.invoke(ctx)
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/click/core.py”, line 1066, in invoke
05:55:37 worker_default.1 | return _process_result(sub_ctx.command.invoke(sub_ctx))
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/click/core.py”, line 1066, in invoke
05:55:37 worker_default.1 | return _process_result(sub_ctx.command.invoke(sub_ctx))
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/click/core.py”, line 895, in invoke
05:55:37 worker_default.1 | return ctx.invoke(self.callback, **ctx.params)
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/click/core.py”, line 535, in invoke
05:55:37 worker_default.1 | return callback(*args, **kwargs)
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/apps/frappe/frappe/commands/scheduler.py”, line 157, in start_worker
05:55:37 worker_default.1 | start_worker(queue)
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/apps/frappe/frappe/utils/background_jobs.py”, line 124, in start_worker
05:55:37 worker_default.1 | Worker(queues, name=get_worker_name(queue)).work()
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/rq/worker.py”, line 483, in work
05:55:37 worker_default.1 | self.register_death()
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/rq/worker.py”, line 282, in register_death
05:55:37 worker_default.1 | p.execute()
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/redis/client.py”, line 2894, in execute
05:55:37 worker_default.1 | return execute(conn, stack, raise_on_error)
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/redis/client.py”, line 2749, in _execute_transaction
05:55:37 worker_default.1 | connection.send_packed_command(all_cmds)
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/redis/connection.py”, line 585, in send_packed_command
05:55:37 worker_default.1 | self.connect()
05:55:37 worker_default.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/redis/connection.py”, line 489, in connect
05:55:37 worker_default.1 | raise ConnectionError(self._error_message(e))
05:55:37 worker_default.1 | redis.exceptions.ConnectionError: Error 111 connecting to localhost:11000. Connection refused.
05:55:37 system | schedule.1 stopped (rc=-15)
05:55:37 redis_cache.1 | 2896:signal-handler (1513126537) Received SIGTERM scheduling shutdown…
05:55:37 redis_cache.1 | 2896:M 13 Dec 05:55:37.828 # User requested shutdown…
05:55:37 redis_cache.1 | 2896:M 13 Dec 05:55:37.829 # Redis is now ready to exit, bye bye…
05:55:37 system | redis_cache.1 stopped (rc=-15)
05:55:37 system | socketio.1 stopped (rc=-15)
05:55:37 system | worker_default.1 stopped (rc=-15)
05:55:37 system | worker_short.1 stopped (rc=-15)
05:55:37 system | worker_long.1 stopped (rc=-15)
05:55:38 web.1 | Exception in thread Thread-2 (most likely raised during interpreter shutdown):
05:55:38 web.1 | Traceback (most recent call last):
05:55:38 web.1 | File “/usr/lib/python2.7/threading.py”, line 801, in __bootstrap_inner
05:55:38 web.1 | File “/home/ubench/frappe-bench/env/local/lib/python2.7/site-packages/watchdog/observers/api.py”, line 237, in run
05:55:38 web.1 | <type ‘exceptions.AttributeError’>: ‘NoneType’ object has no attribute ‘Empty’
05:55:38 system | web.1 stopped (rc=-15)

Kill process on port 11000
sudo lsof -t -i tcp:11000 -s tcp:listen | sudo xargs kill
For reference check