Nishanth Shanmugham nishanths

Think twice before abandoning X11. Wayland breaks everything!

Wayland breaks everything! It is binary incompatible, provides no clear transition path with 1:1 replacements for everything in X11, and is even philosophically incompatible with X11. Hence, if you are interested in existing applications to "just work" without the need for adjustments, then you may be better off avoiding Wayland.

Wayland solves no issues I have but breaks almost everything I need. Even the most basic, most simple things (like xkill) - in this case with no obvious replacement. And usually it stays broken, because the Wayland folks mostly seem to care about Automotive, Gnome, maybe KDE - and alienating everyone else (e.g., people using just an X11 window manager or something like GNUstep) in the process.

Feature comparison

Foldl vs Foldr

I like to call foldr as "fold from the right", while foldl is "fold from the left".

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

	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

	# 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.