postgresql数据库错误-FATAL: could not map anonymous shared memory: Cannot allocate memory

由于项目压测需要，对虚拟机的硬件配置信息由(CPU:24C MEM:32G)改为（CPU:8C MEM:16G），然后重启虚拟机后，postgresql数据库启动失败，具体报错信息如下：

FATAL:  could not map anonymous shared memory: Cannot allocate memory
HINT:  This error usually means that PostgreSQL's request for a shared memory segment exceeded available memory, swap space, or huge pages. To reduce the request size (currently 34610470912 bytes), reduce PostgreSQL's shared memory usage, perhaps by reducing shared_buffers or max_connections.

 网上搜集了下错误原因：由于postgresql设置的shared_buffers参数过大导致（已经超过虚拟机物理内存大小）。

以下为postgresql.conf配置文件内容:

根据性能优化策略,建议shared_buffers参数值设置为本机物理内在的1/4。

把shared_buffers重新设置成4G，保存并退出。重启pg，一切正常。