jutememo

public class Cons<A> implements IList<A> {

    /**
     * リストの先頭要素
     */
    private A x;
    /**
     * リストの残りの要素
     */
    private IList<A> xs;           // 型変数を忘れないように!

szegedi

Table of names of MemoryManagerMXBean and MemoryPoolMXBean instances under
different GC algorithms in Oracle HotSpot VM. Memory managers list the pools
they manage in square brackets; memory pools show their maximum sizes for -Xmx200M setting.

$ java -version
java version "1.6.0_24"
Java(TM) SE Runtime Environment (build 1.6.0_24-b07)
Java HotSpot(TM) 64-Bit Server VM (build 19.1-b02, mixed mode)

SerialGC:

bonifaido

// The MIT License (MIT)
//
// Copyright (c) 2015 Nandor Kracser
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:

jettro

package wsapp;

import org.apache.catalina.websocket.MessageInbound;
import org.apache.catalina.websocket.WsOutbound;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;

/**

thaJeztah

Commit, clone a container

To 'clone' a container, you'll have to make an image of that container first, you can do so by "committing" the container. Docker will (by default) pause all processes running in the container during commit to preserve data-consistency.

For example;

docker commit --message="Snapshot of my container" my_container my_container_snapshot:yymmdd

apangin

_hashCode                               java/lang/Object.hashCode()I
_getClass                               java/lang/Object.getClass()Ljava/lang/Class;
_clone                                  java/lang/Object.clone()Ljava/lang/Object;
_dabs                                   java/lang/Math.abs(D)D
_dsin                                   java/lang/Math.sin(D)D
_dcos                                   java/lang/Math.cos(D)D
_dtan                                   java/lang/Math.tan(D)D
_datan2                                 java/lang/Math.atan2(DD)D
_dsqrt                                  java/lang/Math.sqrt(D)D
_dlog                                   java/lang/Math.log(D)D

0x263b

Random color from string in javascript

Consider a list of strings you need to permanently assign a random color.

First you should turn the string into a hash.

var string = "string"
var hash = 0

mosheeshel

import java.io.IOException;
import java.util.Vector;

/**
 * Created by moshee
 * on: 07/06/17
 * to compile in place: `javac ConsumeHeap.java`
 * Execute: `java -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=/var/log/app-`date +%s`-pid$$.hprof -XX:OnOutOfMemoryError=/opt/app/bin/upload_dump_s3.sh -Xmx2m ConsumeHeap`
 * HeapDumpOnOutOfMemoryError specifies to automatically create a dump when OOM occures
 * HeapDumpPath supplies a path to put that file

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.

miguno

Notes

• Good: very quick snapshotting even for large heap spaces (e.g. works if your JVM process would otherwise timeout and die)
• Bad: such a memory snapshot contains significantly less useful information than YourKit's "enhanced" memory snapshots.

Usage

# 1. Find the relevant JVM pid on the target machine
$ ps ...