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Stephen Johnson smj10j

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@kremalicious
kremalicious / tor-openvpn.sh
Last active September 7, 2024 15:38
Install and configure Tor as proxy for all OpenVPN server traffic
# what we want:
# client -> OpenVPN -> Tor -> Internet
# Install & configure OpenVPN
# https://www.digitalocean.com/community/tutorials/how-to-set-up-an-openvpn-server-on-ubuntu-16-04
# assumed OpenVPN configuration
# 10.8.0.1/24-Subnet
# tun0-Interface
@jult
jult / blockpeers.sh
Last active March 5, 2024 07:33
blocking p2p peer snoopers and evil corp (for Tixati IP filter and such)
#!/bin/sh
# This script runs every other night at 04:56 CET on a webserver I maintain
# Results are always at: https://jult.net/block.txt ( or https://jult.net/block.txt.gz )
# And much smaller, stripped of BS; https://jult.net/bloc.txt
# For use in Tixati IP filter: https://jult.net/bloc.txt.gz !!!
# And finally a txt file with just the bold IP-ranges: https://jult.net/bl.txt (or https://jult.net/bl.txt.gz )
# Download open block-lists, unpack, filter:
curl -s https://www.iblocklist.com/lists.php | grep -A 2 Bluetack | xargs wget -qO - --limit-rate=500k | gunzip -f | egrep -v '^#' > /tmp/xbp
@vasanthk
vasanthk / System Design.md
Last active September 23, 2024 06:28
System Design Cheatsheet

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

  1. Clarify and agree on the scope of the system
  • User cases (description of sequences of events that, taken together, lead to a system doing something useful)
    • Who is going to use it?
    • How are they going to use it?
@stormchasing
stormchasing / Auto Check-In to Southwest Flights.user.js
Last active September 20, 2024 18:42
Auto Check-In to Southwest Flights.user.js
// ==UserScript==
// @name Auto Check-In to Southwest Flights
// @namespace http://www.ryanizzo.com/southwest-auto-check-in/
// @version 1.8
// @author Nicholas Buroojy (http://userscripts.org/users/83813)
// @contributor Ryan Izzo (http://www.ryanizzo.com)
// @contributor JR Hehnly (http://www.okstorms.com @stormchasing)
// @contributor Trevor McClellan (github.com/trevormcclellan)
// @description Automatically check in to Southwest Airline flights at the appropriate time.
// @include https://www.southwest.com/air/check-in/index.html*
@return1
return1 / trim_enabler.txt
Last active May 26, 2024 11:01
TRIM Enabler for OS X Yosemite 10.10.3
#
# UPDATE for 10.10.4+: please consider this patch obsolete, as apple provides a tool called "trimforce" to enable trim support for 3rd party SSDs
# just run "sudo trimforce enable" to activate the trim support from now on!
#
# Original version by Grant Parnell is offline (http://digitaldj.net/2011/07/21/trim-enabler-for-lion/)
# Update July 2014: no longer offline, see https://digitaldj.net/blog/2011/11/17/trim-enabler-for-os-x-lion-mountain-lion-mavericks/
#
# Looks for "Apple" string in HD kext, changes it to a wildcard match for anything
#
# Alternative to http://www.groths.org/trim-enabler-3-0-released/
@johntyree
johntyree / getBlockLists.sh
Last active June 4, 2024 12:30
Make one large blocklist from the bluetack lists on iblocklist.com
#!/usr/bin/env sh
# Download lists, unpack and filter, write to stdout
curl -s https://www.iblocklist.com/lists.php \
| sed -n "s/.*value='\(http:.*=bt_.*\)'.*/\1/p" \
| xargs wget -O - \
| gunzip \
| egrep -v '^#'
@jboner
jboner / latency.txt
Last active September 24, 2024 06:30
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