y-lu’s gists

y-lu / latency.txt

Created October 27, 2018 04:52 — forked from jboner/latency.txt

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

y-lu / ResilienceReferences.md

Created October 27, 2018 04:49 — forked from jboner/ResilienceReferences.md

References from my talk 'Without Resilience, Nothing Else Matters'.

References from my talk 'Without Resilience, Nothing Else Matters'

y-lu / eps2.R

Created June 20, 2017 19:10

R functions to generate and display plots directly on iTerm2 (requires two of my shell scripts on gist: imgcat2 and iterm2-dl2).

	.eps = c()
	eps2 = function(fn, code, width=10, height=10) {
	if(is.na(fn) \|\| fn=="") {
	fn = tempfile("plot-",getwd(),".eps")
	}
	if(length(.eps)==0 \|\| .eps[length(.eps)] != fn) {
	.eps <<- c(.eps, fn)
	}
	setEPS()
	postscript(fn,height=height,width=width)

y-lu / iterm-dl2.sh

Created June 20, 2017 19:06

Script to download file directly from within two nested tmux sessions on iTerm2. Another feature is the script would strip the leading path of the filename.

	#!/bin/bash
	if [ $# -lt 1 ]; then
	echo "Usage: $(basename $0) file ..."
	exit 1
	fi
	for fn in "$@"
	do
	if [ -r "$fn" ] ; then
	[ -d "$fn" ] && { echo "$fn is a directory"; continue; }
	#printf '\033]1337;File=name='`echo -n "$fn" \| base64`";"

y-lu / imgcat2.sh

Created June 20, 2017 19:04

Display image from nested tmux session on iTerm2. This script adds extra escape sequence to make it work within exactly two nested tmux sessions.

	#!/bin/bash

	# tmux requires unrecognized OSC sequences to be wrapped with DCS tmux;
	# <sequence> ST, and for all ESCs in <sequence> to be replaced with ESC ESC. It
	# only accepts ESC backslash for ST.
	function print_osc() {
	#if [[ $TERM == screen* ]] ; then
	# if [[ .$TMUX != . ]] ; then
	#printf "\033Ptmux;\033\033]"
	echo -ne '\033Ptmux;\033\033Ptmux;\033\033\033\033]'