Posted 2023-11-02Updated 2026-03-20a few seconds read (About 58 words)

移除服務

stop [servicename]

systemctl disable [servicename]
sudo trash /etc/systemd/system/[servicename]
sudo trash /etc/systemd/system/[servicename] # and symlinks that might be related
sudo trash /usr/lib/systemd/system/[servicename] 
sudo trash /usr/lib/systemd/system/[servicename] # and symlinks that might be related
systemctl daemon-reload
systemctl reset-failedbash

https://superuser.com/a/936976

Posted 2023-11-01Updated 2026-03-20a minute read (About 187 words)

CMake疑難雜症

Failed to detect a default CUDA architecture或是CMAKE_CUDA_ARCHITECTURES must be non-empty if set

直接告訴CMake nvcc的位置，注意舊的build資料夾要先清掉
-DCMAKE_CUDA_COMPILER=/usr/local/cuda-11.7/bin/nvcc

https://www.cnblogs.com/metaz/p/16919028.html

VS code設定cmake的環境變數

在setting.json加入"cmake.environment": {"CUDA_VER":"11.7"}，說明書:https://github.com/microsoft/vscode-cmake-tools/blob/main/docs/cmake-presets.md#ignored-settings

CMake presets: https://dominikberner.ch/cmake-presets-best-practices/

CMake 系統環境變數設置

https://www.scivision.dev/cmake-environment-variable-scope/

libcuda.so.1 not found

使用find_package(CUDAToolkit)並且在target_link_libraries 加入CUDA::cuda_driver

CMake find_package() 用法

CMake有許多尋找套件的module，例如FindCUDAToolkit，下面連結條列各種find_package()能使用的module

https://cmake.org/cmake/help/latest/manual/cmake-modules.7.html#manual:cmake-modules(7)

Posted 2023-11-01Updated 2026-03-20a few seconds read (About 37 words)

Kafka疑難雜症

服務無法啟動，Kafka Broker doesn’t find cluster id

移除meta.properties.

參考:https://stackoverflow.com/questions/59592518/kafka-broker-doesnt-find-cluster-id-and-creates-new-one-after-docker-restart

Posted 2023-11-01Updated 2026-03-20a few seconds read (About 12 words)

Ubuntu好用套件

資源監視器btop

https://github.com/aristocratos/bpytop#installation

Posted 2023-10-27Updated 2026-03-204 minutes read (About 544 words)

apt相關問題

apt找不到key或重複套件，刪掉有問題的apt key

sudo rm /etc/apt/sources.list.d/*cuda*

查看所有可以安裝的版本

apt-cache madison cuda

https://askubuntu.com/questions/447/how-can-i-see-all-versions-of-a-package-that-are-available-in-the-archive

刪除apt key

顯示所有key
apt-key list顯示結果如下

/etc/apt/trusted.gpg
--------------------
pub   rsa4096 2022-05-05 [SCEA]
      8298 D919 610D E70B 90CE  DAAE EE38 2EF7 8230 7095
uid           [ unknown] TensorRT <svc_tensorrt@nvidia.com>

/etc/apt/trusted.gpg.d/flexiondotorg_ubuntu_nvtop.gpg
-----------------------------------------------------
pub   rsa1024 2011-03-16 [SC]
      824A 27DD 09DE DA33 BF78  3596 2EA8 F357 93D8 809A
uid           [ unknown] Launchpad PPA for Martin Wimpress

/etc/apt/trusted.gpg.d/graphics-drivers_ubuntu_ppa.gpg
------------------------------------------------------
pub   rsa4096 2015-08-12 [SC]
      2388 FF3B E10A 76F6 38F8  0723 FCAE 110B 1118 213C
uid           [ unknown] Launchpad PPA for Graphics Drivers Team

刪掉key
以下面為例，key ID就是最後8碼82307095，sudo apt-key del 82307095就可以刪除

/etc/apt/trusted.gpg
--------------------
pub   rsa4096 2022-05-05 [SCEA]
      8298 D919 610D E70B 90CE  DAAE EE38 2EF7 8230 7095
uid           [ unknown] TensorRT <svc_tensorrt@nvidia.com>

解決Unmet dependencies問題

用dpkg -P package-name來移除有問題的套件，他會顯示不能移除的原因，然後依序移除即可
直接用dpkg安裝套件，如果有缺少的相依套件，之後使用apt install就會顯示E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).錯誤，必須要手動解決相依性問提

apt install使用local repo

參考: https://wiki.debian.org/DebianRepository/Setup?action=show&redirect=DebianRepository%2FHowTo%2FTrivialRepository#trivialArchive

Quick instructions to create a trivial local archive with apt-ftparchive
We use /var/lib/mydebs as the example location

Create the directory

  mkdir -p /var/lib/mydebs
Every time you put new files in the directory, you'll have to scan the directory and update:

  cd /var/lib/mydebs
  apt-ftparchive packages . > Packages
  apt-ftparchive release . > Release
Add this line to /etc/apt/sources.list

  deb [allow-insecure=yes] file:/var/lib/mydebs ./
Now you can install the package normally. If apt-get asks "Install these packages without verification?", answer "Y" to install. That's because this local repository is not signed.

  apt-get update
  apt-get install mydeb

刪除apt gpg key 和repo

https://itslinuxfoss.com/delete-repository-and-gpg-key-ubuntu/#2

查看套件版本

dpkg-query -W tensorrt

用apt 查看可安裝的版本

apt-cache policy <package name>

例如

$ apt-cache policy gparted
gparted:
  Installed: 0.16.1-1
  Candidate: 0.16.1-1
  Version table:
 *** 0.16.1-1 0
        500 http://ubuntu.inode.at/ubuntu/ saucy/main amd64 Packages
        100 /var/lib/dpkg/status

安裝指定版本
sudo apt-get install <package name>=<version>
例如上面的例子

$ sudo apt-get install gparted=0.16.1-1
Reading package lists... Done
Building dependency tree       
Reading state information... Done
gparted is already the newest version.
0 upgraded, 0 newly installed, 0 to remove and 265 not upgraded.

Posted 2023-10-10Updated 2026-03-20a few seconds read (About 58 words)

CodeInterview

BigO

時間複雜度相加還是相乘
相加

Add the Runtimes: 0 (A  +  B) 
1  for  (int  a  :  arrA)  { 
2      print(a); 
3  } 
4 
5  for  (int  b  :  arrB)  { 
6      print(b) ; 
7  }

相乘:

Multiply the Runtimes: O(A* B) 
1  for  (int  a  :  arrA)  { 
2      for  (int  b  :  arrB)  { 
3          print(a  +  " , "  +  b); 
4      }     
5  }