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@jboner
jboner / latency.txt
Last active May 5, 2024 03:12
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
@pbrisbin
pbrisbin / headache.md
Created October 27, 2014 18:55
ZSH startup file headaches

Default behavior dictates the following order for ZSH startup files:

  • /etc/zshenv
  • ~/.zshenv
  • /etc/zprofile (if login shell)
  • ~/.zprofile (if login shell)
  • /etc/zshrc (if interactive)
  • ~/.zshrc (if interactive)
  • /etc/zlogin (if login shell)
  • ~/.zlogin (if login shell)
@moschlar
moschlar / make.conf
Last active February 5, 2024 10:00
Run Gentoo Portage in a cpu cgroup
PORTAGE_IONICE_COMMAND="/usr/local/sbin/portage-cgroup \${PID}"
@dearing
dearing / docker-nftables.conf
Created February 25, 2016 14:26
nftables with docker
# /etc/systemd/system/docker.service.d/docker-nftables.conf
# disable iptables in docker, allowing nftables to do work
[Service]
ExecStart=
ExecStart=/usr/bin/docker daemon -H fd:// --iptables=false
@baetheus
baetheus / README.md
Last active December 17, 2023 14:28
SmartOS Single IP with NAT using VLAN

WARNING

These intructions might work, but they need a bit of attention. I've been reading through ipf and smf documentation and have found a few ways to improve this process. When I have time I'll add that information here, until then, be sure to look into the ipf settings if you're having issues with routing. Good luck!

Foreword

This is a modified version of sjorge's instructions for Single IP with NAT. Those instructions can be found here: https://docu.blackdot.be/snipets/solaris/smartos-nat

The primary difference is that this version does not rely on etherstubs for internal switching, but instead uses a vlan configuration. The benefits of this method over using etherstubs are:

  1. Project Fifo (project-fifo.net) can create vms and zones with vlans, but does not currently have etherstub support.
  2. Vlan switching is supposedly more efficient than creating an etherstub to handle switching. I have not tested this statement.
@ndarville
ndarville / webm.md
Last active September 30, 2023 18:56
4chan’s guide to converting GIF to WebM - https://boards.4chan.org/g/res/41212767

Grab ffmpeg from https://www.ffmpeg.org/download.html

It's a command line tool which means you will have to type things with your keyboard instead of clicking on buttons.

The most trivial operation would be converting gifs:

ffmpeg -i your_gif.gif -c:v libvpx -crf 12 -b:v 500K output.webm
  • -crf values can go from 4 to 63. Lower values mean better quality.
  • -b:v is the maximum allowed bitrate. Higher means better quality.
@return1
return1 / trim_enabler.txt
Last active August 25, 2023 02:59
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/
@izabera
izabera / ircsed
Last active June 21, 2023 14:49
a simple irc bot written in sed
#!/bin/bash
owner=izabera nick=sedirc network=irc.freenode.net
echo "
# send bot data
1 {
s/.*/nick $nick/p
s/.*/user $nick $nick $nick :$nick/p
s/.*/cat factoids 2>\/dev\/null/e; H
b
@twneale
twneale / gist:5245670
Last active April 19, 2023 11:08
.pythonrc file that adds command history and tab completion to my python shell.
'''
Save this file and add the following line to your ~/.bashrc"
export PYTHONSTARTUP="$HOME/.pythonrc"
'''
import os
import readline
import rlcompleter
import atexit
@gmasse
gmasse / gist:4b0c34be3d797cd729d2
Last active February 22, 2022 16:00
OVH custom iPXE boot (dedicated server)