12.1 linux配置优化

12.1.1 内存分配控制

1. vm.overcommit_memory Redis在启动时可能会出现这样的日志：

# WARNING overcommit_memory is set to 0! Background save may fail under low memory
condition. To fix this issue add 'vm.overcommit_memory = 1' to /etc/sysctl.conf and
then reboot or run the command 'sysctl vm.overcommit_memory=1' for this to take effect.

11.1 缓存的收益和成本

图11-1左侧为客户端直接调用存储层的架构，右侧为比较典型的缓存层 +存储层架构，下面分析一下缓存加入后带来的收益和成本。

概览