---
# System prepended metadata

title: 樹梅派筆記-超頻
tags: [Linux, 'null', 樹莓派]

---

---
title: 
description: 
date: 2023-04-16
lang: zh-tw
tags:
  - 樹莓派
  - Linux
  - 
---
# 樹梅派筆記-超頻
在入手樹梅派時有順手買的簡單的鋁質散熱殼，還附有兩個小風扇
一直以來都是用默認設定在跑
但總是覺得有點卡卡的
因此想說來超頻看看
看能壓榨多少性能出來

## 前置需求

確保系統與套件都是最新版本

```zsh=
sudo apt update && sudo apt upgrade -y
sudo apt dist-upgrade -y
```

## 開始超頻

只要簡單修改`config`文件就能超頻了

```zsh=
sudo nano /boot/config.txt
```

找到

```txt=
#uncomment to overclock the arm. 700 MHz is the default.
```
並加入
```txt=
over_voltage=6
arm_freq=2000
# gpu_freq=750
#force_turbo=1
```
* `over_voltage` - 提高核心電壓
* `arm_freq` - 設定最高CPU核心頻率
* `gpu_freq` - 設定最高GPU核心頻率
* `force_turbo` - 強制運行最高頻率(即使負載不高也是)
> `force_turbo=1` 時 `over_voltage`才能大於6

重啟，套用配置
```zsh=
sudo reboot
```
## 結果
可以使用`sysbench`跑CPU壓力測試，用來確認結

安裝`sysbench`
```zsh=
sudo apt install sysbench -y
```

監控CPU核心頻率
```zsh=
watch -n1 vcgencmd measure_clock arm
```
監控溫度
```zsh=
watch -n1 vcgencmd measure_temp
```
開始壓力測試
```zsh=
sysbench --num-threads=8 --test=cpu --cpu-max-prime=20000 run
```
結果
```zsh=
sysbench 1.0.20 (using system LuaJIT 2.1.0-beta3)

Running the test with following options:
Number of threads: 8
Initializing random number generator from current time


Prime numbers limit: 20000

Initializing worker threads...

Threads started!

CPU speed:
    events per second:   935.17

General statistics:
    total time:                          10.0071s
    total number of events:              9366

Latency (ms):
         min:                                    1.27
         avg:                                    8.54
         max:                                   57.53
         95th percentile:                       20.37
         sum:                                79945.24

Threads fairness:
    events (avg/stddev):           1170.7500/91.74
    execution time (avg/stddev):   9.9932/0.01

```
CPU核心頻率
```zsh=
Every 1.0s: vcgencmd measure_clock arm

frequency(48)=2000478464
```
溫度
```zsh=
Every 1.0s: vcgencmd measure_temp

temp=47.7'C
```

的確有到設定的最高CPU核心頻率且溫度也才不到50度

順帶一提，未超頻跑sysbench 測試，需要15秒完成
超完頻只需要10秒，進步巨大

## 總結
從日常使用中，的確有感覺超頻後，跑程式快了很多
只靠被動散熱，未開啟風扇時，溫度也不高
雖然開了風扇可以更低，約40度
但實在太吵了，有股嗡嗡聲
這樣就足夠了

## Ref:
* https://beebom.com/how-overclock-raspberry-pi-4/
* https://www.raspberrypi.com/documentation/computers/config_txt.html#overclocking-options