sholokhov

package pro.sholokhov

// deps
//"org.typelevel" %% "cats-effect" % "3.3.13"
//"org.typelevel" %% "cats-effect-kernel" % "3.1.1"
//"org.typelevel" %% "cats-effect-std" % "3.1.1"
//"com.github.fd4s" %% "fs2-kafka" % "3.0.0-M9"

import cats.effect.{Clock, IO, IOApp}
import fs2.Stream

sholokhov

Advanced Functional Programming with Scala - Notes

Copyright © 2016-2017 Fantasyland Institute of Learning. All rights reserved.

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x

sholokhov

# increase stack size
-Xmx2G
-Xss16M

sholokhov

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        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

sholokhov

You need kernel version at least 2.6.32-431 or higher (check it with uname -r command).

curl -O -sSL https://get.docker.com/rpm/1.7.1/centos-6/RPMS/x86_64/docker-engine-1.7.1-1.el6.x86_64.rpm

Then install package via yum:

yum localinstall --nogpgcheck docker-engine-1.7.1-1.el6.x86_64.rpm

Try to run it:

sholokhov

//
// simple least recently used cache
//

import java.util.LinkedHashMap;
import java.util.*;

class LruCache {

  private LinkedHashMap cache = new LinkedHashMap<String, String>() {