ubuntu - 解决 EC2 上 Ubuntu 16.04 的 overcommit_memory 和 Transparent Huge Pages 上的 Redis 警告

Question

在新的 Ubuntu 16.04 EC2 实例上，警告显示如下:

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.
WARNING you have Transparent Huge Pages (THP) support enabled in your kernel. This will create latency and memory usage issues with Redis. To fix this issue run the command 'echo never > /sys/kernel/mm/transparent_hugepage/enabled' as root, and add it to your /etc/rc.local in order to retain the setting after a reboot. Redis must be restarted after THP is disabled.

如何永久消除它们？

Answer 1

就像警告建议的那样，只需将行 vm.overcommit_memory=1 添加到 /etc/sysctl.conf 的底部，使用 sudo vi/etc/sysctl.conf.

但权限不允许您按照警告建议的那样编辑 THP，因此请改为

sudo apt install hugepages

并将命令 sudo hugeadm --thp-never 添加到您的 .bashrc 的底部，使用类似 sudo vi ~/.bashrc 的内容。

然后只需 sudo reboot 并在下次 SSH 运行 redis-server 时警告就消失了!