我有一台带4Gb RAM的centos服务器。 我正在做一个可能需要几个小时的PHP控制台批处理过程...但是在完成该过程1或2个小时后服务器关闭时它没有完成... 这是日志：
Dec 28 04:39:01 www systemd[1]: Starting Clean php session files...
Dec 28 04:39:02 www systemd[1]: Started Clean php session files.
Dec 28 04:40:04 www systemd[1]: Stopped target Mail Transport Agent.
Dec 28 04:40:04 www systemd[1]: Stopped target Timers.
Dec 28 04:40:04 www systemd[1]: Stopping User Manager for UID 0...
Dec 28 04:40:04 www systemd[1]: Stopping Session 12236053 of user root.
Dec 28 04:40:04 www systemd[1]: Stopped Daily apt upgrade and clean activities.
Dec 28 04:40:04 www systemd[24724]: Stopped target Default.
Dec 28 04:40:04 www systemd[24724]: Stopped target Basic System.
Dec 28 04:40:04 www systemd[24724]: Stopped target Sockets.
Dec 28 04:40:04 www systemd[24724]: Reached target Shutdown.
Dec 28 04:40:04 www systemd[24724]: Starting Exit the Session...
Dec 28 04:40:04 www systemd[24724]: Stopped target Timers.
Dec 28 04:40:04 www systemd[24724]: Stopped target Paths.
Dec 28 04:40:04 www systemd[1]: Stopping Session 12226070 of user root.
Dec 28 04:40:04 www systemd[1]: Stopped Run certbot twice daily.
Dec 28 04:40:04 www systemd[1]: Stopped Daily apt download activities.
Dec 28 04:40:04 www systemd[1]: Stopped Clean PHP session files every 30 mins.
Dec 28 04:40:04 www systemd[1]: Stopped Daily Cleanup of Temporary Directories.
Dec 28 04:40:04 www systemd[1]: Stopped target Graphical Interface.
Dec 28 04:40:04 www systemd[1]: Stopped target Multi-User System.
Dec 28 04:40:04 www systemd[1]: Stopped target Login Prompts.
Dec 28 04:40:04 www systemd[1]: Stopping Console Getty...
Dec 28 04:40:04 www systemd[1]: Stopping Getty on tty2...
Dec 28 04:40:04 www systemd[1]: Stopping LSB: modules.dep creation....
Dec 28 04:40:04 www systemd[1]: Stopping Unattended Upgrades Shutdown...
Dec 28 04:40:04 www systemd[1]: Stopping OpenBSD Secure Shell server...
Dec 28 04:40:04 www systemd[1]: Stopping LSB: Record successful boot for GRUB...
Dec 28 04:40:04 www systemd[1]: Stopping LSB: Start/stop sysstat's sadc...
Dec 28 04:40:04 www systemd[1]: Stopping A high performance web server and a reverse proxy server...
Dec 28 04:40:04 www systemd[1]: Stopping Regular background program processing daemon...
Dec 28 04:40:04 www systemd[1]: Stopping Runit service supervision...
Dec 28 04:40:04 www systemd[1]: Stopping D-Bus System Message Bus...
Dec 28 04:40:04 www systemd[24724]: Received SIGRTMIN+24 from PID 11820 (kill).
Dec 28 04:40:04 www systemd[1]: Stopping LSB: Starts or stops the xinetd daemon....
Dec 28 04:40:04 www systemd[1]: Stopping LSB: Postfix Mail Transport Agent...
Dec 28 04:40:04 www systemd[1]: Stopping The PHP 7.0 FastCGI Process Manager...
Dec 28 04:40:04 www systemd[1]: Stopping vsftpd FTP server...
Dec 28 04:40:04 www rsyslogd: [origin software="rsyslogd" swVersion="8.20.0" x-pid="370" x-info="http://www.rsyslog.com"] exiting on signal 15.
它启动干净的php会话文件然后突然停止所有服务并关闭！
我的代码似乎没问题......我是否需要强制清除代码上的变量？
有什么问题？
由于