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
Swift warm up NSUUID
Search
Johnlin
September 04, 2018
Programming
0
110
Swift warm up NSUUID
Johnlin
September 04, 2018
Tweet
Share
More Decks by Johnlin
See All by Johnlin
用 MLIR 實作 一個 Ruby IR (intermediate representation)
johnlinvc
0
150
Unearth Ruby builtin Gems 發掘 Ruby 的內建 Gems
johnlinvc
0
270
Ruby 型別檢查工具簡介
johnlinvc
0
490
Swift Actor 實作探索
johnlinvc
0
160
用 mruby 來寫跨平台工具
johnlinvc
0
82
Actor model 簡介
johnlinvc
0
190
一起玩 Helm 3
johnlinvc
1
120
為什麼 App 卡卡的
johnlinvc
2
1.2k
如何使用 byebug 來除錯 Ruby 程式
johnlinvc
0
210
Other Decks in Programming
See All in Programming
私の後悔をAWS DMSで解決した話
hiramax
4
210
GitHubとGitLabとAWS CodePipelineでCI/CDを組み比べてみた
satoshi256kbyte
4
220
Android 16 × Jetpack Composeで縦書きテキストエディタを作ろう / Vertical Text Editor with Compose on Android 16
cc4966
1
200
Android端末で実現するオンデバイスLLM 2025
masayukisuda
1
150
個人軟體時代
ethanhuang13
0
320
JSONataを使ってみよう Step Functionsが楽しくなる実践テクニック #devio2025
dafujii
1
530
Ruby Parser progress report 2025
yui_knk
1
440
MCPでVibe Working。そして、結局はContext Eng(略)/ Working with Vibe on MCP And Context Eng
rkaga
5
2.3k
テストカバレッジ100%を10年続けて得られた学びと品質
mottyzzz
2
590
Deep Dive into Kotlin Flow
jmatsu
1
330
Vue・React マルチプロダクト開発を支える Vite
andpad
0
110
為你自己學 Python - 冷知識篇
eddie
1
350
Featured
See All Featured
Building Better People: How to give real-time feedback that sticks.
wjessup
368
19k
Fireside Chat
paigeccino
39
3.6k
Practical Tips for Bootstrapping Information Extraction Pipelines
honnibal
PRO
23
1.4k
BBQ
matthewcrist
89
9.8k
Build your cross-platform service in a week with App Engine
jlugia
231
18k
VelocityConf: Rendering Performance Case Studies
addyosmani
332
24k
We Have a Design System, Now What?
morganepeng
53
7.8k
実際に使うSQLの書き方 徹底解説 / pgcon21j-tutorial
soudai
PRO
188
55k
The Invisible Side of Design
smashingmag
301
51k
The World Runs on Bad Software
bkeepers
PRO
70
11k
[RailsConf 2023] Rails as a piece of cake
palkan
57
5.8k
The Language of Interfaces
destraynor
161
25k
Transcript
Swift ఔࣜখ NSUUID John Lin
ॄኄੋ UUID • ௨༻།Ұࣝผᛰ(Universally Unique Identifier) • 550e8400-e29b-41d4-a716-446655440000 • 32
ݸ16 ਐҐᏐ= 16byte = 128 bitɼ༗ 3.4 * 10 ^ 38 छ߹
UUID ֨ࣜ • xxxxxxxx-xxxx-Mxxx-Nxxx-xxxxxxxxxxxx • ࣈᏐత֨ࣜੋ 8-4-4-4-12 • ଖதၷݸํੋ༻ိදࣔ൛ຊతɻ
UUID ൛ຊ • લ༗ޒݸ൛ຊɼၷछᏓᱪɻ • ࠷ৗ༻తੋ 1 4
UUID1 • timestamp (60 bit) + clock_seq(14bit) + version(6bit) +
MAC address(48bit) = 128bit • ࣌ؒੋኺ 1582/10/15T00:00 ։࢝ࢉʢެ㑕։࢝)ɼ 㑌100 ns ࢉҰݸᄸҐ
UUID 䉰 • timestamp (60 bit) + clock_seq(14bit) + version(6bit)
+ MAC address(48bit) = 128bit • ࡏಉҰػث্ɼ100 ಸඵ㚎ᬋػతൣᅴ༗ 14 bit ༗త࣌ީ။㗞ੜҰᒬతUUIDɼҝ䉰
ੜዬ • Ұݸ൝্༗ࡾेݸਓɼ༗ࢸগၷݸਓಉҰఱੜతػ ੋଟগ䏆ʁ • (1/365)^30 ?
ੜዬ • Ұݸ൝্༗ࡾेݸਓɼ༗ࢸগၷݸਓಉҰఱੜతػ ੋଟগ䏆ʁ • ਖ਼֬తࢉ๏ੋ༻ 1 ݮᎃશᔒ༗ॏෳతػɻब ੋ •
ࡏ 30 ݸਓతگԼେੋ 70 %
UUID1 䉰 • timestamp (60 bit) + clock_seq(14bit) + version(6bit)
+ MAC address(48bit) = 128bit • ࡏಉҰػث্ɼ100 ಸඵ㚎ᬋػతൣᅴ༗ 14 bit ༗త࣌ީ။㗞ੜҰᒬతUUIDɼҝ䉰 • ༻ੜዬɼ100 ಸඵ㚎㗞ੜ 18 ݸ UUID ब༗ 1 % తػ။䉰ɼෆଠద߹շ༻
UUID4 • Swift 㚎ݐత NSUUID & UUID ༗ UUID4 •
random (122 bit) + version (6bit) = 128 bit • 䉰తػখଟ • 㗞ੜ 103 ஹݸ UUID4 ။༗ 10ԯ೭Ұతػ။䉰
NSUUID
UUID • ޭೳ NSUUID Ұᒬɼෆաੋ Struct ൛తɻ • ݐٞ༻Ṝݸൺֱ҆શɻ
݁ • UUID 4 䉰తػᕝత • ༗धཁᘐಛ ID త࣌ީब༻㠧ɼൺࣗݾrandom ؆
ᄸɻ
Q&A
፮ᐔػ • http://slot.miario.com/machines/150067