hellerbarde

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

piscisaureus

Locate the section for your github remote in the .git/config file. It looks like this:

[remote "origin"]
	fetch = +refs/heads/*:refs/remotes/origin/*
	url = [email protected]:joyent/node.git

Now add the line fetch = +refs/pull/*/head:refs/remotes/origin/pr/* to this section. Obviously, change the github url to match your project's URL. It ends up looking like this:

railwaycat

;; Keybonds
(global-set-key [(hyper a)] 'mark-whole-buffer)
(global-set-key [(hyper v)] 'yank)
(global-set-key [(hyper c)] 'kill-ring-save)
(global-set-key [(hyper s)] 'save-buffer)
(global-set-key [(hyper l)] 'goto-line)
(global-set-key [(hyper w)]
                (lambda () (interactive) (delete-window)))
(global-set-key [(hyper z)] 'undo)

Couto

ArchLinux on a Raspberry Pi

Install the system to the SD card

Connect the SD card to your computer and open the terminal.

• Find the disk id

df -h

adamgit

##########################################
#
# c.f. http://stackoverflow.com/questions/3520977/build-fat-static-library-device-simulator-using-xcode-and-sdk-4
#
# Version 2.82
#
# Latest Change:
# - MORE tweaks to get the iOS 10+ and 9- working
# - Support iOS 10+
# - Corrected typo for iOS 1-10+ (thanks @stuikomma)

ethantw

/* 這個檔案適用慣於閱讀「繁體康熙字典舊字形」的用戶 */

/* ＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝注意！＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝
 * 不可將sans-serif（或serif）字體宣告（@font-face）合併為一。
 * Do not combine the sans-serif (or serif) @font-faces into one.
 * ＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝*/


/* 無襯線字體 sans-serif */
@font-face {

areina

Manage your gmail account in emacs with mu4e

There're a lot of combinations to manage your email with emacs, but this works for me. I've a backup and I can manage my daily email.

The stack:

• emacs
• offlineimap
• mu
• mu4e

audreyt

從 SocialCalc 到 EtherCalc

先前在《開源應用程式架構》 一書中，我介紹了 SocialCalc 這個在瀏覽器中運行的試算表編輯器，以取代伺服器為中心的 WikiCalc 架構。SocialCalc 在瀏覽器中執行所有的運算，只有在載入和儲存試算表時才會使用伺服器。

追求效能是 Socialtext 團隊在 2006 年時設計 SocialCalc 的主要目的。重點在於：在 JavaScript 環境下執行客戶端運算，儘管在當年的速度僅有伺服器端 Perl 運算的十分之一，但仍然勝過 AJAX 來回傳輸資料造成的網路延遲：

---

******

railwaycat

#!/usr/bin/perl

# Emacs starter for Emacs mac port

# Thanks to Aquamacs Project and David Reitter

my $args = "";
my $tmpfiles = "";

for my $f (@ARGV) {

siancu

(defun markdown-preview-file ()
  "run Marked on the current file and revert the buffer"
  (interactive)
  (shell-command 
   (format "open -a /Applications/Marked.app %s" 
       (shell-quote-argument (buffer-file-name))))
)
(global-set-key (kbd "C-c m") 'markdown-preview-file)