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enocom / Execution time
Created March 2, 2019 16:16 — forked from ericnormand/00_script.clj
Boilerplate for running Clojure as a shebang script
$ cp script.clj ~/bin/cljtest2
# ~/bin is on my $PATH
$ chmod +x ~/bin/cljtest2
$ time cljtest2 "Yo" "Hey" 1 3 4 - -ff
Hello!
"2019-03-01T17:22:43.564Z"
("Yo" "Hey" "1" "3" "4" "-" "-ff")
268435456
real 0m2.073s

I'm planning on either writing this up in detail or maybe doing a screencast about screencasting, but I'll give a short version here.

On sound quality:

This matters a lot. In decreasing order of importance:

  1. Remove echo. You have to hear this to understand. Set up a mic in front of your mouth and record a sentence. Then, put a thick comforter over you and the mic and say it again at the same distance. Listen to

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

Sharing files using netcat

The receiver

nc -l 5566 > data-dump.sql

Listen on port 5566 and redirect output to data-dump.sql

The sender