tuned 红帽系统调优
1、/proc【记录系统当前的状态，包括进程信息，重启后丢失】
cat /proc/cpuinfo
cat /proc/meminfo
cat /proc/partitions
- /proc/sys #系统各个子系统的配置项，可以通过调整其中的布尔参数来调优；
- /proc/sys 的修改立即生效，重启后丢失；
/etc/sysctl.conf#在其中写入的sysctl配置【对/proc/sys中的内容生效】，重启后不丢失；/etc/sysctl.d/目录下的文件【以数字开头，以.conf结尾】，也对/proc/sys中的内容生效。
echo 0 > /proc/sys/net/ipv4/icmp_echo_ignore_all #只能通过echo方式修改，0为关，1为开；
[root@foundation0 ~]# vim /etc/sysctl.conf #修改在重启后生效；
net.ipv4.icmp_echo_ignore_all = 0
sysctl -p #使sysctl.conf中的配置立即生效；
sysctl -w vm.drop_caches=3 #配置一次性生效的命令；
[root@foundation0 ~]# sysctl -a | grep icmp_echo #列出系统中所有生效的配置；
net.ipv4.icmp_echo_ignore_all = 0
net.ipv4.icmp_echo_ignore_broadcasts = 1
2、/sys #
Sys文件系统是一个类似于proc文件系统的特殊文件系统，用于将系统中的设备组织成层次结构，并向用户模式程序提供详细的内核数据结构信息。
- 其实，就是在用户态可以通过对sys文件系统的访问，来看内核态的一些驱动或者设备等。
[root@servera memory]# ls /sys
block bus class dev devices firmware fs hypervisor kernel module power
3、tuned【rhel6 开始增加的调优工具】
[root@foundation0 sys]# rpm -ql tuned
...omit...
/usr/lib/tuned #存储tuned的各种优化场景的预配置；
/usr/lib/tuned/balanced #均衡优化；
/usr/lib/tuned/balanced/tuned.conf
/usr/lib/tuned/desktop #桌面优化；
/usr/lib/tuned/desktop/tuned.conf
/usr/lib/tuned/functions
/usr/lib/tuned/latency-performance #低延迟性能优化；
/usr/lib/tuned/latency-performance/tuned.conf
/usr/lib/tuned/network-latency #网络延迟优化；
/usr/lib/tuned/network-latency/tuned.conf
/usr/lib/tuned/network-throughput
/usr/lib/tuned/network-throughput/tuned.conf
/usr/lib/tuned/powersave
/usr/lib/tuned/powersave/script.sh
/usr/lib/tuned/powersave/tuned.conf
/usr/lib/tuned/recommend.d
/usr/lib/tuned/recommend.d/50-tuned.conf
/usr/lib/tuned/throughput-performance
/usr/lib/tuned/throughput-performance/tuned.conf
/usr/lib/tuned/virtual-guest
/usr/lib/tuned/virtual-guest/tuned.conf
/usr/lib/tuned/virtual-host
/usr/lib/tuned/virtual-host/tuned.conf
...omit...
3.1、tuned的优化模板
[root@ans-server ~]# tuned-adm list #查看系统中现有的优化模板；
Available profiles:
- balanced - General non-specialized tuned profile
- desktop - Optimize for the desktop use-case
- hpc-compute - Optimize for HPC compute workloads
- latency-performance - Optimize for deterministic performance at the cost of increased power consumption
- network-latency - Optimize for deterministic performance at the cost of increased power consumption, focused on low latency network performance
- network-throughput - Optimize for streaming network throughput, generally only necessary on older CPUs or 40G+ networks
- powersave - Optimize for low power consumption
- throughput-performance - Broadly applicable tuning that provides excellent performance across a variety of common server workloads
- virtual-guest - Optimize for running inside a virtual guest
- virtual-host - Optimize for running KVM guests
Current active profile: virtual-guest
[root@ans-server ~]# tuned-adm profile throughput-performance #修改优化模板，重启后仍然有效；
#拷贝优化模板，修改后可以直接应用【可以大规模拷贝后应用。etc目录下的配置优先于usr/lib下的】：
[root@ans-server ~]# cp -r /usr/lib/tuned/throughput-performance/ /etc/tuned/rh442
[root@ans-server ~]# tuned-adm profile rh442 #应用优化模板；
plugin_之后的内容，都是优化模板文件中的类别【ini 格式的[type]或type=】：
man tuned.conf#记录有tuned优化模板的帮助；
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_audio.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_bootloader.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_cpu.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_disk.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_eeepc_she.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_modules.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_mounts.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_net.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_scheduler.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_script.py #可以自动加载脚本；
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_scsi_host.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_selinux.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_sysctl.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_sysfs.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_systemd.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_usb.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_video.py
/usr/lib/python3.6/site-packages/tuned/plugins/plugin_vm.py
脚本举例
压缩/etc目录下的文件：
#!/bin/bash
DIR=/etc
tar -zcf /backup/etc-$(date -d '1 day ago' +%Y%m%d).tar.gz $DIR
date -d '1 day ago' #显示字符串中定义的时间；
[root@servera ~]# date +%Y-%m-%d=%H:%M:%S #定义date命令输出的格式
2021-10-19=11:37:41
