use iotop to debug I/O issue
1. # sudo apt-get install iotop
2. # sudo iotop
3. start another terminal
4. # sync
5. to monitor the process to see if it's hanging.
# top
6. start another terminal, print free memory every 2 seconds
# free -ms 2
7. Start another terminal,
# sudo nohup free -ms 2 &> ~/Documents/log/free.log &
# sudo nohup top -b -d 5 &> ~/Documents/log/top.log &
# sudo nohup iotop -b -d 2 -o -t &> ~/Documents/log/iotop.log &
# iostat -x 1 or collectl -sD
# atop
Refer: https://read01.com/zh-tw/Le32AL.html#.YjUy9H9BxEY
(2016/05/13 來源：紅黑聯盟)
1. 以管理員身份執行 cmd
2. "slmgr.vbs -upk" ---- 卸載證書
"slmgr.vbs -rearm"則為重置電腦的許可證書狀態
3. 重新導入相關的OEM證書及Keyslmgr.vbs -ipk 6K2KY-BFH24-PJW6W-9GK29-TMPWP
slmgr.vbs -ilc 證書路徑
其他命令及其作用：
slmgr.vbs -dli (顯示許可證信息)
slmgr.vbs -xpr (當前許可證狀態的截止日期)
slmgr.vbs -dlv (顯示詳細的許可證信息)
slmgr.vbs -ilc lenovo.oemcert.100036.xrm-ms
其它查看授權的方法：上網下載 slic toolkit 查看看 BIOS 有沒有windows 授權
Windows 10 彩盒版(完整版 Full Version) (Retail) 與 隨機版(OEM) 的使用
1. 隨機版(OEM)： 輸入金鑰之後會綁定主機板，Win 10 build 1607 之後，若有用微軟帳號綁定轉成數位授權，則可以移機到新的主機
2. 數位版啟用授權之轉移同隨機版
(也就是免費更新上WIN10跟從M$商城買的授權走隨機版規則)
(例如：原本是彩盒版 Win7 免費更新上 Win10，就會變成隨機版)
3. 彩盒版(完整版 Full Version) (Retail)：理論上可以任意的移機，限制是同時只能有一台是合法使用。但實際上，微軟的伺服器好像會偵測安裝次數，可能被限制安裝次數，若有問題時，還是可打電話到微軟要求解決。最好保留購買的發票與彩盒金鑰。
建議：
1. 若是使用隨機版(OEM)，可考慮用微軟帳號綁定轉成數位授權，以後可以自由移機到新的主機，舊的會自動失效，不須事先取消綁定。先到微軟網站，登入你的帳號，查看帳戶有沒有連結授權。
2. 隨機版(OEM)不綁定微軟帳號轉成數位授權，要先取消綁定主機板授權，然後，才可以移動授權到新的主機板
按照MS的規則
彩盒版 = 可單機序號啟動+轉移、可綁定MS帳號啟動+轉移
隨機版 = 可單機序號啟動(不可轉移)、可綁定MS帳號啟動(不可轉移)，
後來被發現微軟啟動規則BUG，才出現 [隨機版綁定MS帳號啟動+轉移] 的方法
至於隨機版用主機板維修的理由做電話序號啟動+轉移，這是微軟在放水(或是說相信客戶的誠實)，按照規則是可以拒絕轉移的
上網下載 slic toolkit 查看看 BIOS 有沒有windows 授權
可用 DOS Prompt 的 slmgr 查看是 Retail， OEM or Volume
slmgr /dli
refer to :
1. https://www.lifewire.com/slmgr-command-4684499
2. https://www.windowscentral.com/how-determine-if-license-oem-retail-volume-windows-10
3. https://softwarekeep.com/help-center/how-to-plug-in-your-product-key-with-slmgr-and-slui
4. https://www.mobile01.com/topicdetail.php?f=300&t=5484013&p=2
5. https://www.mobile01.com/topicdetail.php?f=300&t=6394804
How to set up USB for Virtualbox?
1. Install Extension Pack
For USB 2.0 and USB 3.0 we need to install the free (but closed source) VirtualBox Extension Pack from the VirtualBox download page
2. Become a "vboxuser" in Host machine (local machine)
To be able to get access to an attached USB device, the Ubuntu host user needs to be in the vboxusers group. Add your user to this group by running the following command
sudo usermod -aG vboxusers <username>
and reboot or logout/login.
3. Activate USB support in VirtualBox Manager
Shut down your virtual machine and open USB settings in the VirtualBox Manager. Tick Enable USB Controllerand USB 2.0 (EHCI) Controller or USB 3.0 (xHCI) Controller.
Suggestion: using USB 2.0 (EHCI) Controller
4. Select host USB device for access from the guest
To grant access to USB devices we need to select a device to disable in the host and to enable in the guest (this is a precaution to avoid simultaneous access from host and guest). This can be done from the panel Devices menu or by right mouse click in the bottom panel of the VirtualBox Manager on the USB icon:
Tick the device you need in the guest, untick it if you need it in the host. If you can't see your USB device in that list, it means that VirtualBox cannot access your host USB devices. Make sure your user is added to the vboxusers group and that you restarted your host.
The selected device will immediately be accessible from the guest.
Refer to : https://askubuntu.com/questions/25596/how-to-set-up-usb-for-virtualbox
Method 1: (This method is failed to "#! /usr/bin/env")
putting alias in the user's ~/.bashrc
example:
alias python=python3
Method 2: (This method is OK to "#! /usr/bin/env")
$ whereis python3
$ ls -lisa /usr/bin/python*
$ sudo ln -s /usr/bin/python3 /usr/bin/python
Method 3:
$ sudo apt install python-is-python3
1. Settings / Region & Language / Input Sources / Manage Installed Language
Add Chinese
2. Settings / Region & Language / Input Sources / +
Select ... ,
then Other,
then select Chinese, Press Add
3. Settings / Region & Language / Input Sources / Chinese
Press Chinese, Select Chinese (Chewing)
Refer to https://askubuntu.com/questions/63420/how-to-fix-virtualboxs-copy-and-paste-to-host-machine
sudo apt install virtualbox-guest-x11 --reinstall
VBoxClient-all --clipboard
I used --reinstall option because of I had virtualbox-guest-x11 package installed and before reinstalling it I had:$ VBoxClient-all --clipboard VBoxClient: error: No service specified. Quitting because nothing to do!
3) After reboot screen resolution jumps to its minimal value, so
Run Guest OS (Ubuntu) / Settings / Displays / Resolution The default way to take
Almost all Linux distributions and desktop environments support these keyboard
Let’s take a look at the list of keyboard shortcuts you can utilize:
PrtSc – Save a screenshot of the entire screen to the “Pictures” directory.
Shift + PrtSc – Save a screenshot of a specific region to Pictures.
Alt + PrtSc – Save a screenshot of the current window to Pictures.
Ctrl + PrtSc – Copy the screenshot of the entire screen to the clipboard.
Ctrl + Shift + PrtSc – Copy the screenshot of a specific region to the clipboard.
Ctrl + Alt + PrtSc – Copy the screenshot of the current window to the clipboard.
1. Add the following in ~/.bash_profile
#! /bin/bash #----------------------------------------------------------------- # Bash autocompletion for Git if [ -f ~/.git-completion.sh ]; then source ~/.git-completion.sh fi if [ -f ~/.git-prompt.sh ]; then source ~/.git-prompt.sh fi # PS1 may be replaced PS1='${debian_chroot:+($debian_chroot)}\[\033[01;32m\][\w]\[\033[0m\]\[\033[1;36m\]$(__git_ps1)\[\033[0;33m\]\[\033[0m\]$ ' #PS1='\[\033[01;32m\]\u@\h\[\033[00m\]: \[\033[01;34m\]\w \[\033[0m\]\[\033[1;36m\] $(__git_ps1)\[\033[0;33m\]\[\033[0m\]$ ' #PS1='[\u@\h \W$(__git_ps1 " (%s)")]\$ ' #PS1="[\[\033[1;32m\]\w\[\033[0m\]] \[\033[0m\]\[\033[1;36m\]\$(git_branch)\[\033[0;33m\]\$(git_since_last_commit)\[\033[0m\]$ " #PS1="[\[\033[1;32m\]\w\[\033[0m\]] \[\033[0m\]\[\033[1;33m\]\$(__git_ps1)\[\033[0;33m\]\[\033[0m\]$ "
2. Download https://github.com/git/git/blob/master/contrib/completion/git-completion.bash
and rename by git-completion.sh
3. download https://github.com/git/git/blob/master/contrib/completion/git-prompt.sh
$ mv git-completion.sh ~/.git-completion.sh$ mv git-prompt.sh ~/.git-prompt.sh$ chmod 775 .git-completion.sh$ chmod 775 .git-prompt.sh
4.
$ source ~/.bashrcor
$ source ~/.bash_profileReference result
