Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Garbage Collection of Oracle JDK6
Search
Kengo TODA
June 13, 2012
Technology
1
150
Garbage Collection of Oracle JDK6
A simple introduction for GC, mainly about Oracle JDK6.
Kengo TODA
June 13, 2012
Tweet
Share
More Decks by Kengo TODA
See All by Kengo TODA
JavaとGroovyで書かれたGradleプラグインをKotlinで書き直した話 / Converted a Gradle plugin from Groovy&Java to Kotlin
eller86
0
1k
ヒューマンスキル / The Humanskills
eller86
0
520
医療機関向けシステムの信頼性 / Reliability of systems for medical institutions
eller86
0
290
Server-side Kotlinを使うスタートアップでどんなDetektルールが育ったか / Detekt rules made in start-up working with Server-side Kotlin
eller86
0
1.3k
Java開発者向けのKotlin Gradleビルドスクリプト入門 / Gradle Build Script in Kotlin 101
eller86
1
1.4k
Goodbye JSR305, Hello JSpecify!
eller86
2
4.7k
Java8〜16におけるバイトコード生成の変化 / Changes of Bytecode Generation from Java 8 to 16
eller86
4
4.2k
Javaプログラミングの体験向上に関する活動 / DX enhancement around Java programming
eller86
0
3.7k
静的解析ツールで生産性向上
eller86
1
880
Other Decks in Technology
See All in Technology
塩野義製薬様のAWS統合管理戦略:Organizations設計と運用の具体例
tkikuchi
0
220
地域DXにおけるGrafana活用事例
wacky
0
260
Graph Database と Generative AI の素敵な関係
oracle4engineer
PRO
15
2.5k
組織デバイスのための効率的なアプリケーション更新戦略
kenchan0130
0
360
Oracle Database 23ai 新機能#4 Application Continuity
oracle4engineer
PRO
0
130
コード✕AIーソフトウェア開発者のための生成AI実践入門~
yuhattor
4
880
Oracle Database 23ai 新機能#4 Real Application Clusters
oracle4engineer
PRO
0
170
Semantic Kernel の Agent 機能試してみた!
okazuki
1
180
Vespaを利用したテクいベクトル検索
szdr
2
200
LeSSはスクラムではない!?LeSSにおけるスクラムマスターの振る舞い方とは / Scrum Master Behavior in LeSS
toma_sm
0
210
Product Utilization of Large Language Models Starting Today
ymatsuwitter
3
1.6k
I tried the newly introduced certification "Applied Skills" on Microsoft Learn
mappie_kochi
0
270
Featured
See All Featured
GraphQLとの向き合い方2022年版
quramy
43
13k
4 Signs Your Business is Dying
shpigford
180
21k
Making the Leap to Tech Lead
cromwellryan
131
8.9k
Testing 201, or: Great Expectations
jmmastey
38
7k
The Art of Delivering Value - GDevCon NA Keynote
reverentgeek
4
120
Design and Strategy: How to Deal with People Who Don’t "Get" Design
morganepeng
126
18k
Infographics Made Easy
chrislema
239
18k
Bash Introduction
62gerente
608
210k
Templates, Plugins, & Blocks: Oh My! Creating the theme that thinks of everything
marktimemedia
26
2k
The Straight Up "How To Draw Better" Workshop
denniskardys
232
130k
Into the Great Unknown - MozCon
thekraken
31
1.4k
Fight the Zombie Pattern Library - RWD Summit 2016
marcelosomers
231
17k
Transcript
GarbageCollection Don’t you need to pay attention for memory? Kengo
TODA 2012/June/13 126݄12Ր༵
Summary for previous Object size = size of header +
Σ (field). Array requires contiguous space to store. Why we have to care? 126݄12Ր༵
Answer: Generational Garbage Collection cannot handle too long contiguous space
effectively 126݄12Ր༵
What’s GC? Memory management algorithm The reason why we don’t
have to `free` in Java 126݄12Ր༵
Type of GC Mark and sweep garbage collection Copying garbage
collection Generational garbage collection Garbage first garbage collection (G1GC) etc. 126݄12Ր༵
Currently we use... Generational garbage collection with copying GC for
new generation with mark & sweep GC for old generation 126݄12Ր༵
What is Generation? Divide heap into 4 areas Tenured area
is ‘old generation’ and others belongs to ‘new generation’ Survivor 1 Survivor 2 Eden Tenured new old 126݄12Ր༵
What is Generation? All data are stored in Eden area
at 1st Data is moved by GC Survivor 1 Survivor 2 Eden Tenured new old 126݄12Ր༵
What is Generation? Object data cannot span border If there
is no space to put data in specified area, we have to boot GC to keep space Survivor 1 Survivor 2 Eden Tenured new old NG OK OK 126݄12Ր༵
key point Long contiguous space is danger because Throw OOME
if it’s longer than heap area (not whole heap size) Boot GC and slow JVM 126݄12Ր༵
References The Java™ Virtual Machine Specification Sensible Sanitation -- Understanding
the IBM Java Garbage Collector 126݄12Ր༵