ORA-27300: OS system dependent operation:sendmsg failed with status: 105 ORA-27301: OS failure message: No buffer space available

早上查看数据库alert日志，发现如下ORA-报错：

kgxpvfynet: mtype: 61 process 6460 failed because of a resource problem in the OS. The OS has most likely run out of buffers (rval: 4)
Errors in file /u01/app/oracle/diag/rdbms/orcl/orcl2/trace/orcl2_ora_6460.trc (incident=176003):
ORA-00603: ORACLE server session terminated by fatal error
ORA-27504: IPC error creating OSD context
ORA-27300: OS system dependent operation:sendmsg failed with status: 105
ORA-27301: OS failure message: No buffer space available
ORA-27302: failure occurred at: sskgxpsnd2

经过搜索MOS ，给出的结论是： 这是由于网络缓冲区保留空间不足造成的。

vm.min_free_kbytes should be set in the order of 0.4% of total Physical Memory

解决方案：

1. 增大操作系统内核参数vm.min_free_kbytes 的值

由于本机物理内存128G，故此处增大到：  vm.min_free_kbytes = 524288

sysctl -p 使参数生效

2. 还建议修改lo网卡MTU的值

#ifconfig lo mtu 16436

#vi  /etc/sysconfig/network-scripts/ifcfg-lo 

ORA-27300: OS system dependent operation:sendmsg failed with status: 105 ORA-27301: OS failure message: No buffer space available

原文：https://www.cnblogs.com/sky2088/p/9210350.html