| # 30 minutes Lisp in Ruby | |
| # Hong Minhee <http://dahlia.kr/> | |
| # | |
| # This Lisp implementation does not provide a s-expression reader. | |
| # Instead, it uses Ruby syntax like following code: | |
| # | |
| # [:def, :factorial, | |
| # [:lambda, [:n], | |
| # [:if, [:"=", :n, 1], | |
| # 1, |
In August 2007 a hacker found a way to expose the PHP source code on facebook.com. He retrieved two files and then emailed them to me, and I wrote about the issue:
http://techcrunch.com/2007/08/11/facebook-source-code-leaked/
It became a big deal:
http://www.techmeme.com/070812/p1#a070812p1
The two files are index.php (the homepage) and search.php (the search page)
| Latency Comparison Numbers | |
| -------------------------- | |
| L1 cache reference 0.5 ns | |
| Branch mispredict 5 ns | |
| L2 cache reference 7 ns 14x L1 cache | |
| Mutex lock/unlock 25 ns | |
| Main memory reference 100 ns 20x L2 cache, 200x L1 cache | |
| Compress 1K bytes with Zippy 3,000 ns | |
| Send 1K bytes over 1 Gbps network 10,000 ns 0.01 ms | |
| Read 4K randomly from SSD* 150,000 ns 0.15 ms |
| <?xml version="1.0" encoding="UTF-8" ?> | |
| <opml version="1.0"> | |
| <head> | |
| <title>寸志 subscriptions in Digg Reader</title> | |
| </head> | |
| <body> | |
| <outline text="Framer Blog" title="Framer Blog" type="rss" xmlUrl="http://framerjs.tumblr.com/rss" htmlUrl="http://framerjs.tumblr.com/" /> | |
| <outline text="粉丝日志" title="粉丝日志" type="rss" xmlUrl="http://blog.fens.me/feed/" htmlUrl="http://blog.fens.me" /> | |
| <outline text="AngularJS" title="AngularJS" type="rss" xmlUrl="http://blog.angularjs.org/feeds/posts/default" htmlUrl="http://blog.angularjs.org/" /> | |
| <outline text="blog.izs.me" title="blog.izs.me" type="rss" xmlUrl="http://blog.izs.me/rss" htmlUrl="http://blog.izs.me/" /> |
| <?php | |
| /** | |
| * ---------------------------------------------------------------------------------------- | |
| * Based on `https://github.com/mecha-cms/mecha-cms/blob/master/engine/plug/converter.php` | |
| * ---------------------------------------------------------------------------------------- | |
| */ | |
0.5 ns5 ns (on a bad CPU architecture you're pretty much screwed)7 ns25 ns100 ns3,000 ns20,000 ns250,000 ns
| L1 cache reference 0.5 ns | |
| Branch mispredict 5 ns | |
| L2 cache reference 7 ns 14x L1 cache | |
| Mutex lock/unlock 25 ns | |
| Main memory reference 100 ns 20x L2 cache, 200x L1 cache | |
| Compress 1K bytes with Zippy 3,000 ns | |
| Send 1K bytes over 1 Gbps network 10,000 ns 0.01 ms | |
| Read 1 MB sequentially from memory 250,000 ns 0.25 ms | |
| Round trip within same datacenter 500,000 ns 0.5 ms | |
| Read 1 MB sequentially from SSD 1,000,000 ns 1 ms 4X memory |
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| // by Erik Wrenholt | |
| import java.util.*; | |
| class Mandelbrot | |
| { | |
| static int BAILOUT = 16; | |
| static int MAX_ITERATIONS = 1000; | |
| private static int iterate(float x, float y) | |
| { |
| // | |
| // _oo0oo_ | |
| // o8888888o | |
| // 88" . "88 | |
| // (| -_- |) | |
| // 0\ = /0 | |
| // ___/`---'\___ | |
| // .' \\| |// '. | |
| // / \\||| : |||// \ | |
| // / _||||| -:- |||||- \ |