Norimasa Nabeta NorimasaNabeta

Overview

Some notes about:

Explaining why current day Linux memory swap thrashing still happens (as of 2016).
Mitigating "stop the world" type thrashing issues on a Linux workstation when it's under high memory pressure and where responsiveness is more important than process completion.
Prioritizing and limiting memory use.
Older ulimit versus newer CGroup options.

These notes assume some basic background knowledge about memory management, ulimits and cgroups.

This guide now lives at https://github.com/joyeusenoelle/GuideToMastodon/ - please check there for updates, and feel free to submit a PR if you have suggestions or want to submit a translation!

	@startuml
	' uncomment the line below if you're using computer with a retina display
	' skinparam dpi 300
	!define Table(name,desc) class name as "desc" << (T,#FFAAAA) >>
	' we use bold for primary key
	' green color for unique
	' and underscore for not_null
	!define primary_key(x) <b>x</b>
	!define unique(x) <color:green>x</color>
	!define not_null(x) <u>x</u>

	#include <time.h> // Robert Nystrom
	#include <stdio.h> // @munificentbob
	#include <stdlib.h> // for Ginny
	#define r return // 2008-2019
	#define l(a, b, c, d) for (i y=a;y\
	<b; y++) for (int x = c; x < d; x++)
	typedef int i;const i H=40;const i W
	=80;i m[40][80];i g(i x){r rand()%x;
	}void cave(i s){i w=g(10)+5;i h=g(6)
	+3;i t=g(W-w-2)+1;i u=g(H-h-2)+1;l(u