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make it work, make it right

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make it work, make it right
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@jboner
jboner / latency.txt
Last active June 4, 2025 07:41
Latency Numbers Every Programmer Should Know
Latency Comparison Numbers (~2012)
----------------------------------
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 3 us
Send 1K bytes over 1 Gbps network 10,000 ns 10 us
Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD
@masak
masak / explanation.md
Last active June 1, 2025 10:45
How is git commit sha1 formed

Ok, I geeked out, and this is probably more information than you need. But it completely answers the question. Sorry. ☺

Locally, I'm at this commit:

$ git show
commit d6cd1e2bd19e03a81132a23b2025920577f84e37
Author: jnthn <[email protected]>
Date:   Sun Apr 15 16:35:03 2012 +0200

When I added FIRST/NEXT/LAST, it was idiomatic but not quite so fast. This makes it faster. Another little bit of masak++'s program.

@nrk
nrk / command.txt
Created April 2, 2012 19:19
Using ffprobe to get info from a file in a nice JSON format
ffprobe -v quiet -print_format json -show_format -show_streams "lolwut.mp4" > "lolwut.mp4.json"
@oodavid
oodavid / README.md
Last active March 11, 2025 21:41 — forked from aronwoost/README.md
Deploy your site with git

Deploy your site with git

This gist assumes:

  • you have a local git repo
  • with an online remote repository (github / bitbucket etc)
  • and a cloud server (Rackspace cloud / Amazon EC2 etc)
    • your (PHP) scripts are served from /var/www/html/
    • your webpages are executed by apache
  • apache's home directory is /var/www/
@trodrigues
trodrigues / gist:1023167
Created June 13, 2011 16:51
Checkout only certain branches with git-svn
If you want to clone an svn repository with git-svn but don't want it to push all the existing branches, here's what you should do.
* Clone with git-svn using the -T parameter to define your trunk path inside the svnrepo, at the same time instructing it to clone only the trunk:
git svn clone -T trunk http://example.com/PROJECT
* If instead of cloning trunk you just want to clone a certain branch, do the same thing but change the path given to -T:
git svn clone -T branches/somefeature http://example.com/PROJECT
@dahnielson
dahnielson / UUID.php
Last active January 14, 2025 05:54
Pure PHP UUID generator
<?php
/**
* UUID class
*
* The following class generates VALID RFC 4122 COMPLIANT
* Universally Unique IDentifiers (UUID) version 3, 4 and 5.
*
* UUIDs generated validates using OSSP UUID Tool, and output
* for named-based UUIDs are exactly the same. This is a pure
* PHP implementation.
@jwage
jwage / SplClassLoader.php
Last active August 16, 2024 17:36
Add MIT license.
<?php
/*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,