karmanov

# download: remote -> local
scp user@remote_host:remote_file local_file 

# upload: local -> remote
scp local_file user@remote_host:remote_file

karmanov

Latency Comparison Numbers
--------------------------
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
Send 1K bytes over 1 Gbps network        10,000   ns    0.01 ms
Read 4K randomly from SSD*              150,000   ns    0.15 ms

karmanov

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

karmanov

# Path to your oh-my-zsh installation.
export ZSH=/Users/karmanov/.oh-my-zsh
export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk1.8.0_65.jdk/Contents/Home

# Set name of the theme to load.
# Look in ~/.oh-my-zsh/themes/
# Optionally, if you set this to "random", it'll load a random theme each
# time that oh-my-zsh is loaded.
#ZSH_THEME="robbyrussell"
ZSH_THEME="maran"

karmanov

Clean OSX setup:
0. Common:
	0.1 Show hidden file: defaults write com.apple.finder AppleShowAllFiles YES / NO
	0.2 Homebrew
1. Java 
	1.1 https://docs.oracle.com/javase/8/docs/technotes/guides/install/mac_jdk.html
	
2. Сделайте сброс SMC
Сброс настроек контроллера, отвечающего за работу внутренних компонентов MacBook, 
был и остается действенным способом устранения различного рода неполадок. 

karmanov

With a custom Collector:


import java.util.Map;
import java.util.stream.Collector;
import javax.json.Json;
import javax.json.JsonObject;
import javax.json.JsonObjectBuilder;

karmanov

private RSAPrivateKey readPrivateKey() throws Exception {
        BufferedReader rdr = new BufferedReader(new StringReader(privateKeyString));
        String pkcs8Pem = rdr.lines().collect(Collectors.joining());
        pkcs8Pem = pkcs8Pem
                .replace("-----BEGIN PRIVATE KEY-----", "")
                .replace("-----END PRIVATE KEY-----", "")
                .replaceAll("\\s+", "");

        byte[] pkcs8EncodedBytes = Base64.decode(pkcs8Pem);

karmanov

#!/bin/sh

COUNTER=0
while true
do
  TIME=`gdate +%s.%N`

  # if [ $((COUNTER%10)) -eq 0 ];
  # then
  #   # every tenth invocation will be more than a minute old