tuned 추가

OS/TUNING/INFLUXDB/HW/README.md

@@ -4,7 +4,7 @@
 
 | CPU | MEM | DISK | 비고 |
 | ------ | ------ | ------ | ------ |
-|`Intel(R) Xeon(R) Silver 4110 CPU @ 2.10GHz` * 2 | 128 GB (DDR4) | SSD 1.92 TB * 4 (RAID 1+0) |
+|`Intel(R) Xeon(R) Silver 4110 CPU @ 2.10GHz` * 2 | 128 GB (DDR4) | SSD 1.74 TB * 4 (RAID 1+0) |
 
 ## CPU
 

OS/TUNING/INFLUXDB/TUNED/README.md

+[![logo](https://www.hongsnet.net/images/logo.gif)](https://www.hongsnet.net)
+
+# OS Version
+
+```bash
+# cat /etc/redhat-release
+CentOS Linux release 7.9.2009 (Core)
+```
+
+# Kernel Version
+
+```bash
+# uname -a
+Linux 호스트네임 3.10.0-1160.el7.x86_64 #1 SMP Mon Oct 19 16:18:59 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
+```
+
+# tuned status
+
+```bash
+# systemctl status tuned
+● tuned.service - Dynamic System Tuning Daemon
+   Loaded: loaded (/usr/lib/systemd/system/tuned.service; enabled; vendor preset: enabled)
+   Active: active (running) since Thu 2022-01-13 11:29:34 KST; 3 months 27 days ago
+     Docs: man:tuned(8)
+           man:tuned.conf(5)
+           man:tuned-adm(8)
+ Main PID: 1434 (tuned)
+   CGroup: /system.slice/tuned.service
+           └─1434 /usr/bin/python2 -Es /usr/sbin/tuned -l -P
+```
+
+# tuned profile status
+
+```bash
+# tuned-adm active
+Current active profile: powersave
+```
+
+또한 다음과 같이 CPU Clock이 **powersave** 프로파일에 맞게 평시 낮게 조정되어 있다.
+
+```bash
+# grep -E '^model name|^cpu MHz' /proc/cpuinfo
+model name      : Intel(R) Xeon(R) Silver 4110 CPU @ 2.10GHz
+cpu MHz         : 1200.926
+model name      : Intel(R) Xeon(R) Silver 4110 CPU @ 2.10GHz
+cpu MHz         : 1200.542
+model name      : Intel(R) Xeon(R) Silver 4110 CPU @ 2.10GHz
+cpu MHz         : 1200.926
+model name      : Intel(R) Xeon(R) Silver 4110 CPU @ 2.10GHz
+cpu MHz         : 1200.926
+model name      : Intel(R) Xeon(R) Silver 4110 CPU @ 2.10GHz
+cpu MHz         : 1200.054
+...중략
+```
+
+# tuned profile setting
+
+최적의 성능을 발휘할 수 있도록 다음과 같이 `latency-performance` 프로파일로 변경한다.
+
+```bash
+# tuned-adm profile latency-performance
+```
+
+이제 CPU의 Clock이 `성능(performance)`을 기준으로 조정된다.
+
+```bash
+# grep -E '^model name|^cpu MHz' /proc/cpuinfo
+model name      : Intel(R) Xeon(R) Silver 4110 CPU @ 2.10GHz
+cpu MHz         : 2399.926
+model name      : Intel(R) Xeon(R) Silver 4110 CPU @ 2.10GHz
+cpu MHz         : 2399.926
+model name      : Intel(R) Xeon(R) Silver 4110 CPU @ 2.10GHz
+cpu MHz         : 2399.926
+model name      : Intel(R) Xeon(R) Silver 4110 CPU @ 2.10GHz
+cpu MHz         : 2399.926
+...중략
+```
+
+그런데, **model name**의 2.10GHz Clock이 **2.399GHz**로 조정되어 있는데, 이는 다음과 같이 **performance governors**에 따른 결과 이다. 
+
+```bash
+# cpupower frequency-info
+analyzing CPU 0:
+  driver: intel_pstate
+  CPUs which run at the same hardware frequency: 0
+  CPUs which need to have their frequency coordinated by software: 0
+  maximum transition latency:  Cannot determine or is not supported.
+  hardware limits: 800 MHz - 3.00 GHz
+  available cpufreq governors: performance powersave
+  current policy: frequency should be within 800 MHz and 3.00 GHz.
+                  The governor "performance" may decide which speed to use
+                  within this range.
+  current CPU frequency: 2.40 GHz (asserted by call to hardware)
+  boost state support:
+    Supported: yes
+    Active: yes
+```
+