Oracle process number: 0
Windows thread id: 8032, image: ORACLE.EXE
ORA-00020: maximum number of processes 150 exceeded
Died during process startup with error 20 (seq=5582)
OPIRIP: Uncaught error 20. Error stack:
ORA-00020: maximum number of processes (150) exceeded
Dump file c:\\oracle\\product\\10.2.0\\admin\\hoegh\\bdump\\hoegh_ora_8032.trc
Thu Apr 30 01:27:31 2015
ORACLE V10.2.0.4.0 - 64bit Production vsnsta=0
vsnsql=14 vsnxtr=3
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
Windows NT Version V6.1 Service Pack 1
CPU : 24 - type 8664, 12 Physical Cores
Process Affinity : 0x0000000000000000
Memory (Avail/Total): Ph:3350M/8181M, Ph+PgF:10812M/16361M
Instance name: hoegh
Redo thread mounted by this instance: 1
Oracle process number: 0
Windows thread id: 8032, image: ORACLE.EXE
ORA-00020: maximum number of processes 150 exceeded
Died during process startup with error 20 (seq=5650)
OPIRIP: Uncaught error 20. Error stack:
ORA-00020: maximum number of processes (150) exceeded
Dump file c:\\oracle\\product\\10.2.0\\admin\\hoegh\\bdump\\hoegh_ora_8032.trc
Thu Apr 30 09:54:12 2015
ORACLE V10.2.0.4.0 - 64bit Production vsnsta=0
vsnsql=14 vsnxtr=3
Oracle Database 10g Enterprise Edition Release 10.2.0.4.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing options
Windows NT Version V6.1 Service Pack 1
CPU : 24 - type 8664, 12 Physical Cores
Process Affinity : 0x0000000000000000
Memory (Avail/Total): Ph:3857M/8181M, Ph+PgF:11421M/16361M
Instance name: hoegh
Redo thread mounted by this instance: 1
Oracle process number: 0
Windows thread id: 8032, image: ORACLE.EXE
? ? ? ? 至于为什么新增设备会产生大量连接，到现在还没有搞清楚，怀疑和操作系统有关，这台设备安装的操作系统是windows xp embeded裁剪版系统，据说在安装系统时不太顺利；在故障设备上启动应用程序，通过select sid,serial#,program,terminal from v$session;监控实时会话信息，会话数不断增多，直到触碰阀值，数据库报错，问题成功复现；
? ? ? 我们又找来另外一台相同配置、相同操作系统的设备进行测试，没有出现这个问题。最后，只能把这台设备重装系统。
? ? ? 下面总结一下ORA-12516错误的解决办法：
?一、一般是由于数据库的当前会话数不满足造成的，可以视业务需要增加processes和sessions参数的大小，这二者的关系是：sessions=(1.1*processes+5)；
?二、如果存在类似上述案例的恶意连接，可以按照上述步骤找到问题session，直接kill相关进程。