rabbitmq 服务启动失败，timeout

rabbitmq设置为随系统启动时，一起启动。
在系统启动时，启动失败。centos7.2版本。
rabbitmq 3.3.5
查看rabbitmq日志文件： /var/log/rabbitmq/rabbit@vStack.log,  未发现异常信息。
=INFO REPORT==== 2-Aug-2016::13:39:04 ===
node          : rabbit@vStack
home dir    : /var/lib/rabbitmq
config file(s) : /etc/rabbitmq/rabbitmq.config
cookie hash : kdOFmK006jilLIKWRas3dQ==
log          : /var/log/rabbitmq/rabbit@vStack.log
sasl log    : /var/log/rabbitmq/rabbit@vStack-sasl.log
database dir : /var/lib/rabbitmq/mnesia/rabbit@vStack

=INFO REPORT==== 2-Aug-2016::13:39:04 ===
Limiting to approx 924 file handles (829 sockets)

=INFO REPORT==== 2-Aug-2016::13:39:04 ===
Memory limit set to 3184MB of 7960MB total.

=INFO REPORT==== 2-Aug-2016::13:39:04 ===
Disk free limit set to 50MB

=INFO REPORT==== 2-Aug-2016::13:39:04 ===
msg_store_transient: using rabbit_msg_store_ets_index to provide index

=INFO REPORT==== 2-Aug-2016::13:39:04 ===
msg_store_persistent: using rabbit_msg_store_ets_index to provide index

=WARNING REPORT==== 2-Aug-2016::13:39:04 ===
msg_store_persistent: rebuilding indices from scratch

=INFO REPORT==== 2-Aug-2016::13:39:20 ===
started TCP Listener on [::]:5672

通过 #service rabbitmq-server status，显示timeout问题。
[root@vStack rabbitmq]# service rabbitmq-server status
Redirecting to /bin/systemctl status  rabbitmq-server.service
● rabbitmq-server.service - RabbitMQ broker
Loaded: loaded (/usr/lib/systemd/system/rabbitmq-server.service; enabled; vendor preset: disabled)
Active: failed (Result: timeout) since 二 2016-08-02 13:39:22 CST; 19min ago
  Process: 1007 ExecStart=/usr/lib/rabbitmq/bin/rabbitmq-server (code=killed, signal=TERM)
Main PID: 1007 (code=killed, signal=TERM)

8月 02 13:39:04 vStack rabbitmq-server[1007]: RabbitMQ 3.3.5. Copyright (C) 2007-2014 GoPivotal, Inc.
8月 02 13:39:04 vStack rabbitmq-server[1007]: ##  ##    Licensed under the MPL.  See http://www.rabbitmq.com/
8月 02 13:39:04 vStack rabbitmq-server[1007]: ##  ##
8月 02 13:39:04 vStack rabbitmq-server[1007]: ##########  Logs: /var/log/rabbitmq/rabbit@vStack.log
8月 02 13:39:04 vStack rabbitmq-server[1007]: ######  ##       /var/log/rabbitmq/rabbit@vStack-sasl.log
8月 02 13:39:04 vStack rabbitmq-server[1007]: ##########
8月 02 13:39:22 vStack systemd[1]: rabbitmq-server.service start operation timed out. Terminating.
8月 02 13:39:22 vStack systemd[1]: Failed to start RabbitMQ broker.
8月 02 13:39:22 vStack systemd[1]: Unit rabbitmq-server.service entered failed state.
8月 02 13:39:22 vStack systemd[1]: rabbitmq-server.service failed.

重新启动，#service rabbitmq-server start 服务又正常。

初步评估是资源不足导致，初提升资源外，不知道其他有没有好的策略。