简介：
从 RHEL/Centos 6.3 之后，引入了一套新的调优工具 tuned ，带来了大量的调优配置，可以针对不同的业务服务调整不同的优化策略。也旨在于简化调优的实施，充分利用系统资源与能效。
另外，RHEL 6 和 RHEL 7 的 tuned 设置还是有一点区别的。
安装部署：
1. 安装 tuned 服务
# yum -y install tuned
2. 查看当前系统中有的 tuned profile
# tuned-adm list
Available profiles: - balanced - General non-specialized tuned profile - desktop - Optmize for the desktop use-case - 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. This is the default profile for RHEL7. - virtual-guest - Optimize for running inside a virtual guest. - virtual-host - Optimize for running KVM guests Current active profile: powersave
3. 查看默认 profile 目录
# ls -lt /usr/lib/tuned/
total 20 drwxr-xr-x. 2 root root 23 May 6 01:09 throughput-performance drwxr-xr-x. 2 root root 23 Mar 24 17:52 virtual-host drwxr-xr-x. 2 root root 23 Mar 24 17:52 virtual-guest drwxr-xr-x. 2 root root 39 Mar 24 17:52 powersave drwxr-xr-x. 2 root root 23 Mar 24 17:52 network-throughput drwxr-xr-x. 2 root root 23 Mar 24 17:52 network-latency drwxr-xr-x. 2 root root 23 Mar 24 17:52 latency-performance drwxr-xr-x. 2 root root 23 Mar 24 17:52 desktop drwxr-xr-x. 2 root root 23 Mar 24 17:52 balanced -rw-r--r--. 1 root root 12532 Jun 17 2016 functions -rw-r--r--. 1 root root 1288 Jun 17 2016 recommend.conf
4. web profile 配置要求
磁盘的调度算法为 deadline 将打开的最大文件数设置成 65535 启用该tuned profile 后，广播消息 “Tuned Profile change to webserver !”，通知各个终端已经更改了 tuned profile。
5. 配置新的名为 webserver 的 tuned Profile
复制一个模板 profile 到 /etc/tuned/ 目录下 # cp -R /usr/lib/tuned/balanced /etc/tuned/webserver 查看新建的 Profile 结构数# tree /etc/tuned/webserver
/etc/tuned/webserver/ └── tuned.conf 0 directories, 1 file
提示：
在 RHEL 6 中，还有 ktune 服务及文件，RHEL 7 中已经全部集成到了 tuned.conf 中了，更多参数和详细信息请移步↓：
RHEL 6 tuned/ktune 调优参考
RHEL 7 tuned 调优参考
修改 tuned.conf 文件
# cd /etc/tuned/webserver/
# vi tuned.conf ... [main] summary=This is a web server tuned profile # 此处是改 profile 文件的描述
...
[disk]
# device=sda # 如果不写，则是该设备连接的所有磁盘
elevator=deadline # 将磁盘 IO 的调度算法更改为 deadline
...
[my_sysctl] # 自定义的 sysctl 字段 type=sysctl # 类型为 sysctl fs.file-max=655350 # 修改最大打开的文件数
...
[my_script]
type=script
script=script.sh # 不写全路劲的话，默认主目录为 webserver，即默认会在 /etc/tuned/webserver 目录下去找该脚本文件
...
在 webserver tuned profile 目录中新建一个 script.sh 脚本 [名字可以随便起]
# vi script.sh
#!/bin/sh . /usr/lib/tuned/functions start() { wall "Tuned Profile change to webserver !" return 0 } stop() { return 0 } process $@
提示：
其实不用写这么复杂，直接下面这样也是可以的。
#!/bin/bash
wall xxxx
# chmod +x script.sh
需要赋予他执行权限，否则会报错，无法正常被执行。
6. 使该 profile 生效
# tuned-adm profile webserver
Broadcast message from root@xxx (Sat May 6 05:10:04 2017): Tuned Profile change to webserver !
7. 验证
# tuned-adm active
Current active profile: webserver
# sysctl -a |grep 'fs.file-max' fs.file-max = 655350
# cat /sys/block/sda/queue/scheduler noop [deadline] cfq
全部都已经生效了。设置成功，另外，我们可以输入如下命令查看一下 tuned.conf 到底都能写入何种类型的字段【type=xxx】
# rpm -ql tuned | grep 'plugins/plugin_.*.py$' /usr/lib/python2.7/site-packages/tuned/plugins/plugin_audio.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_bootloader.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_cpu.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_disk.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_eeepc_she.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_modules.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_mounts.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_net.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_scheduler.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_script.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_scsi_host.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_selinux.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_sysctl.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_sysfs.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_usb.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_video.py /usr/lib/python2.7/site-packages/tuned/plugins/plugin_vm.py
更多 tuned.conf 的参数也可以参考红帽官方网站的 tuned 章节。另外，性能调优是在出现问题后或者瓶颈后才需要调整，不要一味的盲目调节，否则只会适得其反。
且调且珍惜
