glennblock

git fetch upstream
git reset --hard upstream/master

jboner

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

MohamedAlaa

tmux shortcuts & cheatsheet

start new:

tmux

start new with session name:

tmux new -s myname

plentz

# to generate your dhparam.pem file, run in the terminal
openssl dhparam -out /etc/nginx/ssl/dhparam.pem 2048

sloria

The Best of the Best Practices (BOBP) Guide for Python

A "Best of the Best Practices" (BOBP) guide to developing in Python.

In General

Values

• "Build tools for others that you want to be built for you." - Kenneth Reitz
• "Simplicity is alway better than functionality." - Pieter Hintjens

mattiaslundberg

# Install ARCH Linux with encrypted file-system and UEFI
# The official installation guide (https://wiki.archlinux.org/index.php/Installation_Guide) contains a more verbose description.

# Download the archiso image from https://www.archlinux.org/
# Copy to a usb-drive
dd if=archlinux.img of=/dev/sdX bs=16M && sync # on linux

# Boot from the usb. If the usb fails to boot, make sure that secure boot is disabled in the BIOS configuration.

# Set swedish keymap

jkreps

Producer

Setup
bin/kafka-topics.sh --zookeeper esv4-hcl197.grid.linkedin.com:2181 --create --topic test-rep-one --partitions 6 --replication-factor 1
bin/kafka-topics.sh --zookeeper esv4-hcl197.grid.linkedin.com:2181 --create --topic test --partitions 6 --replication-factor 3

Single thread, no replication

bin/kafka-run-class.sh org.apache.kafka.clients.tools.ProducerPerformance test7 50000000 100 -1 acks=1 bootstrap.servers=esv4-hcl198.grid.linkedin.com:9092 buffer.memory=67108864 batch.size=8196

rjames86

Last updated: 2017-03-18

Searching for Files

Find images in a directory that don't have a DateTimeOriginal

exiftool -filename -filemodifydate -createdate -r -if '(not $datetimeoriginal) and $filetype eq "JPEG"' .

###Output photos that don't have datetimeoriginal to a CSV### Note this can take a long time if you have a lot of jpgs

psayre23

Below are the Big O performance of common functions of different Java Collections.


List                 | Add  | Remove | Get  | Contains | Next | Data Structure
---------------------|------|--------|------|----------|------|---------------
ArrayList            | O(1) |  O(n)  | O(1) |   O(n)   | O(1) | Array
LinkedList           | O(1) |  O(1)  | O(n) |   O(n)   | O(1) | Linked List
CopyOnWriteArrayList | O(n) |  O(n)  | O(1) |   O(n)   | O(1) | Array

binaerbaum

# Install ARCH Linux with encrypted file-system and UEFI
# The official installation guide (https://wiki.archlinux.org/index.php/Installation_Guide) contains a more verbose description.

# Download the archiso image from https://www.archlinux.org/
# Copy to a usb-drive
dd if=archlinux.img of=/dev/sdX bs=16M && sync # on linux

# Boot from the usb. If the usb fails to boot, make sure that secure boot is disabled in the BIOS configuration.

# Set swiss-french keymap