连续两天凌晨进程莫名消失，gc日志正常，jvm无error dump日志
查看linux日志 vim /var/log/messages
Jul 19 04:45:03 Aliyun-kernel: Out of memory: Kill process 22339 (java) score 85 or sacrifice child
Jul 19 04:45:03 Aliyun-kernel: Killed process 22339, UID 505, (java) total-vm:4292684kB, anon-rss:686596kB, file-rss:256kB
Jul 20 05:25:03 Aliyun-kernel: Out of memory: Kill process 5279 (java) score 61 or sacrifice child
Jul 20 05:25:03 Aliyun-kernel: Killed process 5279, UID 505, (java) total-vm:3986036kB, anon-rss:492212kB, file-rss:228kB
Jul 20 05:25:03 Aliyun-kernel: grep invoked oom-killer: gfp_mask=0x201da, order=0, oom_adj=0, oom_score_adj=0
Jul 20 05:25:03 Aliyun-kernel: grep cpuset=/ mems_allowed=0
Jul 20 05:25:03 Aliyun-kernel: Pid: 6093, comm: grep Not tainted 2.6.32-573.22.1.el6.x86_64 #1
Jul 20 05:25:03 Aliyun-kernel: Out of memory: Kill process 5293 (java) score 61 or sacrifice child
Jul 20 05:25:03 Aliyun-kernel: Killed process 5293, UID 505, (java) total-vm:3986036kB, anon-rss:492212kB, file-rss:228kB
Mem: 8061236k total, 6536516k used, 1524720k free, 117740k buffers
Swap: 0k total, 0k used, 0k free, 1545768k cached
http://www.importnew.com/12285.html
jvm不建议使用swap，换机器