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@jboner
jboner / latency.txt
Last active May 9, 2024 06:01
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
@kconragan
kconragan / keyrepeat.shell
Last active December 4, 2023 03:40
Enable key repeat in Apple Lion for Sublime Text in Vim mode
# Mac OS X Lion introduced a new, iOS-like context menu when you press and hold a key
# that enables you to choose a character from a menu of options. If you are on Lion
# try it by pressing and holding down 'e' in any app that uses the default NSTextField
# for input.
#
# It's a nice feature and continues the blending of Mac OS X and iOS features. However,
# it's a nightmare to deal with in Sublime Text if you're running Vintage (Vim) mode,
# as it means you cannot press and hold h/j/k/l to move through your file. You have
# to repeatedly press the keys to navigate.
@saetia
saetia / gist:1623487
Last active May 1, 2024 19:55
Clean Install – OS X 10.11 El Capitan

OS X Preferences


most of these require logout/restart to take effect

# Enable character repeat on keydown
defaults write -g ApplePressAndHoldEnabled -bool false

# Set a shorter Delay until key repeat
@doctyper
doctyper / gist:1411283
Created November 30, 2011 22:11
Add latency to localhost
# enable
sudo ipfw pipe 1 config bw 50KBytes/s delay 100ms
sudo ipfw add 1 pipe 1 src-port 80
sudo ipfw add 2 pipe 1 dst-port 80
# disable
sudo ipfw delete 1
sudo ipfw delete 2