djspiewak

Schedulers

As Cats Effect is a runtime system, it ultimately must deal with the problem of how best to execute the programs which are defined using its concrete implementation (IO). Fibers are an incredibly powerful model, but they don't map 1:1 or even 1:n with any JVM or JavaScript construct, which means that some interpretation is required. The fashion in which this is achieved has a profound impact on the performance and elasticity of programs written using IO.

This is true across both the JVM and JavaScript, and while it seems intuitive that JavaScript scheduling would be a simpler problem (due to its single-threaded nature), there are still some significant subtleties which become relevant in real-world applications.

JVM

IO programs and fibers are ultimately executed on JVM threads, which are themselves mapped directly to kernel threads and, ultimately (when scheduled), to processors. Determining the optimal method of mapping a real-world, concurrent application down to kernel-level thr

smola

#!/bin/bash
set -e

if [[ -z ${K8S_JVM_POD} ]]; then
    echo "K8S_JVM_POD not defined"
    exit 1
fi

EXEC="kubectl exec ${K8S_JVM_POD}"
CP="kubectl cp ${K8S_JVM_POD}"

djspiewak

Thread Pools

Thread pools on the JVM should usually be divided into the following three categories:

1. CPU-bound
2. Blocking IO
3. Non-blocking IO polling

Each of these categories has a different optimal configuration and usage pattern.

PurpleBooth

Project Title

One Paragraph of project description goes here

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes. See deployment for notes on how to deploy the project on a live system.

Prerequisites

psayre23

Below are the Big O performance of common functions of different Java Collections.


List                 | Add  | Remove | Get  | Contains | Next | Data Structure
---------------------|------|--------|------|----------|------|---------------
ArrayList            | O(1) |  O(n)  | O(1) |   O(n)   | O(1) | Array
LinkedList           | O(1) |  O(1)  | O(n) |   O(n)   | O(1) | Linked List
CopyOnWriteArrayList | O(n) |  O(n)  | O(1) |   O(n)   | O(1) | Array