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@cdown
cdown / gist:1163649
Last active July 25, 2024 03:11
Bash urlencode and urldecode
urlencode() {
# urlencode <string>
old_lc_collate=$LC_COLLATE
LC_COLLATE=C
local length="${#1}"
for (( i = 0; i < length; i++ )); do
local c="${1:$i:1}"
case $c in
@jboner
jboner / latency.txt
Last active July 28, 2024 12:12
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
@hellerbarde
hellerbarde / latency.markdown
Created May 31, 2012 13:16 — forked from jboner/latency.txt
Latency numbers every programmer should know

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

@aponxi
aponxi / sql-mongo_comparison.md
Last active February 21, 2024 11:56
MongoDb Cheat Sheets

SQL to MongoDB Mapping Chart

SQL to MongoDB Mapping Chart

In addition to the charts that follow, you might want to consider the Frequently Asked Questions section for a selection of common questions about MongoDB.

Executables

The following table presents the MySQL/Oracle executables and the corresponding MongoDB executables.

@freeformz
freeformz / WhyILikeGo.md
Last active October 6, 2022 23:31
Why I Like Go

A slightly updated version of this doc is here on my website.

Why I Like Go

I visited with PagerDuty yesterday for a little Friday beer and pizza. While there I got started talking about Go. I was asked by Alex, their CEO, why I liked it. Several other people have asked me the same question recently, so I figured it was worth posting.

Goroutines

The first 1/2 of Go's concurrency story. Lightweight, concurrent function execution. You can spawn tons of these if needed and the Go runtime multiplexes them onto the configured number of CPUs/Threads as needed. They start with a super small stack that can grow (and shrink) via dynamic allocation (and freeing). They are as simple as go f(x), where f() is a function.

@willurd
willurd / web-servers.md
Last active July 26, 2024 13:45
Big list of http static server one-liners

Each of these commands will run an ad hoc http static server in your current (or specified) directory, available at http://localhost:8000. Use this power wisely.

Discussion on reddit.

Python 2.x

$ python -m SimpleHTTPServer 8000
@jmoiron
jmoiron / valuer.go
Created October 14, 2013 18:03
Example uses of sql.Scanner and driver.Valuer
package main
import (
"bytes"
"compress/gzip"
"database/sql/driver"
"errors"
"fmt"
"github.com/jmoiron/sqlx"
_ "github.com/mattn/go-sqlite3"
@arunoda
arunoda / gist:7790979
Last active February 16, 2024 14:05
Installing SSHPass

Installing SSHPASS

SSHPass is a tiny utility, which allows you to provide the ssh password without using the prompt. This will very helpful for scripting. SSHPass is not good to use in multi-user environment. If you use SSHPass on your development machine, it don't do anything evil.

Installing on Ubuntu

apt-get install sshpass

Installing on OS X

@sergiotapia
sergiotapia / md5-example.go
Last active December 5, 2023 03:53
Golang - How to hash a string using MD5.
import (
"crypto/md5"
"encoding/hex"
)
func GetMD5Hash(text string) string {
hasher := md5.New()
hasher.Write([]byte(text))
return hex.EncodeToString(hasher.Sum(nil))
}
@vratiu
vratiu / .bash_aliases
Last active July 26, 2024 20:56
Git shell coloring
# Customize BASH PS1 prompt to show current GIT repository and branch.
# by Mike Stewart - http://MediaDoneRight.com
# SETUP CONSTANTS
# Bunch-o-predefined colors. Makes reading code easier than escape sequences.
# I don't remember where I found this. o_O
# Reset
Color_Off="\[\033[0m\]" # Text Reset