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@esaul
esaul / springer-free-maths-books.md
Created December 28, 2015 16:56 — forked from bishboria/springer-free-maths-books.md
Springer have made a bunch of maths books available for free, here are the direct links
#!/bin/sh
# Alot of these configs have been taken from the various places
# on the web, most from here
# https://github.com/mathiasbynens/dotfiles/blob/master/.osx
# Set the colours you can use
black='\033[0;30m'
white='\033[0;37m'
red='\033[0;31m'

OS X Screencast to animated GIF

This gist shows how to create a GIF screencast using only free OS X tools: QuickTime, ffmpeg, and gifsicle.

Screencapture GIF

Instructions

To capture the video (filesize: 19MB), using the free "QuickTime Player" application:

In Rails 3

NOTE: This post now lives (and kept up to date) on my blog: http://hakunin.com/rails3-load-paths

If you add a dir directly under app/

Do nothing. All files in this dir are eager loaded in production and lazy loaded in development by default.

If you add a dir under app/something/

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns                     on recent CPU
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 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 4X memory

#!/bin/sh
# Some things taken from here
# https://github.com/mathiasbynens/dotfiles/blob/master/.osx
# Set the colours you can use
black='\033[0;30m'
white='\033[0;37m'
red='\033[0;31m'
green='\033[0;32m'
@esaul
esaul / http_get.go
Last active August 29, 2015 14:06 — forked from ijt/http_get.go
package main
import (
"fmt"
"http"
"io/ioutil"
"os"
)
func main() {
@esaul
esaul / gist:1854433
Created February 17, 2012 17:13
Retry and clear failed Resque jobs
def retry_and_clear(args)
case args
when Integer
Resque::Failure.requeue(args)
Resque::Failure.remove(args)
when String
all_jobs = Resque::Failure.all(0, Resque::Failure.count)
all_jobs.each_with_index do |job, idx|
begin
Resque::Failure.requeue(idx)