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@bradtraversy
bradtraversy / django_cheat_sheet.md
Last active February 11, 2024 05:20
Django command cheat sheet
View django_cheat_sheet.md

Django 2.x Cheat Sheet

Creating a virtual environment

We need to create a virtual env for our app to run in: More Here Run this command in whatever folder you want to create your venv folder

python -m venv ./venv
@wr0ngway
wr0ngway / rubytrace
Last active March 14, 2023 11:02
Uses gdb to dump ruby backtraces for all threads, and displays them in an easily readable format
View rubytrace
#!/bin/bash
PID=$1
RUBY_BINARY=`which ruby`
BT_FILENAME="/tmp/ruby-backtrace-$PID-$(date +%s).txt"
cmdfile=$(mktemp)
cat <<EOF > $cmdfile
set \$old_stdout = dup(1)
set \$old_stderr = dup(2)
@ewherrmann
ewherrmann / resque.rake
Last active July 2, 2020 00:36
Collection of Resque related custom rake tasks from around the web
View resque.rake
require 'resque/tasks'
namespace :resque do
def del(key)
Resque.redis.keys(key).each { |k| Resque.redis.del(k) }
end
desc "Resque setup according to installation guide"
task :setup => :environment
@jboner
jboner / latency.txt
Last active February 22, 2024 16:41
Latency Numbers Every Programmer Should Know
View latency.txt
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
@vitobotta
vitobotta / resque-recovery.sh
Created May 24, 2012 18:53
Resque: automatically kill stuck workers and retry failed jobs
View resque-recovery.sh
#!/bin/bash
# Also see: http://vitobotta.com/resque-automatically-kill-stuck-workers-retry-failed-jobs/
[[ -f /tmp/retry-failed-resque-jobs ]] && rm /tmp/retry-failed-resque-jobs
ps -eo pid,command |
grep [r]esque |
grep "Processing" |
while read PID COMMAND; do
@benfyvie
benfyvie / object_diagnostics.rb
Created December 22, 2011 17:30 — forked from eric/object_diagnostics.rb
Tools for debugging memory bloat using Ruby's built in ObjectSpace
View object_diagnostics.rb
module ObjectDiagnostics
extend self
#This is handy when you want to determine what types of objects are contributing to memory bloat
#returns the change in object counts since the last time this method was called
def change_in_object_counts
#this will start all counts at 0 for the initial run
@previous_counts ||= Hash.new(0)