ORA-1092 : opitsk aborting process---killed by oom killer

oracle version:Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - 64bit Production

os version:Linux x86 64-bit
oracle alert日志报错：

opiodr aborting process unknown ospid (19506) as a result of ORA-1092
Wed Jul 15 16:18:42 2015
ORA-1092 : opitsk aborting process
Wed Jul 15 16:18:52 2015
opiodr aborting process unknown ospid (19555) as a result of ORA-1092
Wed Jul 15 16:18:52 2015
ORA-1092 : opitsk aborting process
Wed Jul 15 16:18:52 2015
opiodr aborting process unknown ospid (19504) as a result of ORA-1092
Wed Jul 15 16:18:52 2015
ORA-1092 : opitsk aborting process
Wed Jul 15 16:19:03 2015
Instance terminated by PMON, pid = 2238

操作系统报错日志：

Jul 15 16:18:27 allwincredit kernel: Out of memory: Kill process 2258 (oracle) score 46 or sacrifice child
Jul 15 16:18:27 allwincredit kernel: Killed process 2258, UID 1101, (oracle) total-vm:7431020kB, anon-rss:9700kB, file-rss:1132084kB
Jul 15 16:18:27 allwincredit kernel: java invoked oom-killer: gfp_mask=0x201da, order=0, oom_adj=0, oom_score_adj=0
Jul 15 16:18:27 allwincredit kernel: java cpuset=/ mems_allowed=0-2
Jul 15 16:18:27 allwincredit kernel: Pid: 4217, comm: java Not tainted 2.6.32-358.el6.x86_64 #1

Linux以下有个特性叫OOM killer（Out Of Memory killer），这个东西会在系统内存耗尽的情况下跳出来，选择性的干掉一些进程以求释放一些内存。
这次非常不幸，干掉了oracle的进程。

什么是oom killer:
http://www.360doc.com/content/11/1119/18/7492958_165786637.shtml
怎样关闭oom killer:http://www.cnblogs.com/itfriend/archive/2011/12/14/2287160.html