大è¦æ¨¡ã‚·ã‚¹ãƒ†ãƒ ã§ã® Linux ã®ãƒ¡ãƒ¢ãƒªç®¡ç†
(This post is also available in English.) ã“ã®è¨˜äº‹ã¯ Linux memory management at scale ã‚’ 著者㮠Chris Down ã•ã‚“ã®è¨±å¯ を得㦠Hiroaki Nakamura ãŒæ—¥æœ¬èªžã«ç¿»è¨³ã—ãŸã‚‚ã®ã§ã™ã€‚ 原文ã®ãƒ©ã‚¤ã‚»ãƒ³ã‚¹ 㯠CC BY-SA 4.0 ã§ã‚ã‚Šã€ç¿»è¨³ã®ãƒ©ã‚¤ã‚»ãƒ³ã‚¹ã‚‚åŒã˜ã CC BY 4.0 ã¨ã—ã¾ã™ã€‚ cgroup2 プãƒã‚¸ã‚§ã‚¯ãƒˆã§ã®ç§ã®ä»•äº‹ã®ä¸€éƒ¨ã¨ã—㦠Linux システムã®ãƒªã‚½ãƒ¼ã‚¹ç®¡ç†ã«ã¤ã„ã¦ã‚¨ãƒ³ã‚¸ãƒ‹ã‚¢ã¨è©±ã™ã“ã¨ã«å¤šãã®æ™‚é–“ã‚’ã‹ã‘ã¦ãã¾ã—ãŸã€‚ ã“れらã®ä¼šè©±ã‚’通ã˜ã¦ã©ã‚“ã©ã‚“明らã‹ã«ãªã£ã¦ã㟠1 ã¤ã®äº‹å®Ÿã¯å¤šãã®ã‚¨ãƒ³ã‚¸ãƒ‹ã‚¢ã¯ã€ã‚·ãƒ‹ã‚¢ SRE ãŸã¡ã§ã•ãˆã‚‚〠Linux ã®ãƒ¡ãƒ¢ãƒªç®¡ç†ã«ã¤ã„ã¦ã„ãã¤ã‹ã®ã‚ˆãã‚る誤解をæŒã£ã¦ã„ã¦ã€ãã—ã¦ãã‚ŒãŒå½¼ã‚‰ãŒã‚µãƒãƒ¼ãƒˆã™ã‚‹ã‚µãƒ¼ãƒ“スやシステムãŒæœ¬æ¥ç¢ºå®Ÿã«ç¨¼åƒã—ãŸã‚ŠåŠ¹çŽ‡çš„
スワップã®å¼è·ï¼šã‚ˆãã‚る誤解を解ã
(This post is also available in English.) ã“ã®è¨˜äº‹ã¯ In defence of swap: common misconceptions ã‚’ 著者㮠Chris Down ã•ã‚“ã®è¨±å¯ を得㦠Hiroaki Nakamura ãŒæ—¥æœ¬èªžã«ç¿»è¨³ã—ãŸã‚‚ã®ã§ã™ã€‚ 原文ã®ãƒ©ã‚¤ã‚»ãƒ³ã‚¹ 㯠CC BY-SA 4.0 ã§ã‚ã‚Šã€ç¿»è¨³ã®ãƒ©ã‚¤ã‚»ãƒ³ã‚¹ã‚‚åŒã˜ã CC BY 4.0 ã¨ã—ã¾ã™ã€‚ 長文をèªã¿ãŸããªã„æ–¹ã¸ã®è¦ç´„： スワップをæŒã¤ã“ã¨ã¯æ£ã—ã機能ã™ã‚‹ã‚·ã‚¹ãƒ†ãƒ ã®ã‹ãªã‚Šé‡è¦ãªãƒã‚¤ãƒ³ãƒˆã§ã™ã€‚ スワップãŒç„¡ã‘ã‚Œã°ã€ã¾ã¨ã‚‚ãªãƒ¡ãƒ¢ãƒªç®¡ç†ã‚’実ç¾ã™ã‚‹ã“ã¨ã¯é›£ã—ããªã‚Šã¾ã™ã€‚ スワップã¯ä¸€èˆ¬çš„ã«ç·Šæ€¥äº‹æ…‹ç”¨ã®ãƒ¡ãƒ¢ãƒªã‚’å–å¾—ã™ã‚‹ãŸã‚ã®ã‚‚ã®ã§ã¯ãªãã€ãƒ¡ãƒ¢ãƒªã®å›žåŽã‚’å¹³ç‰ã«åŠ¹çŽ‡çš„ã«è¡Œã†ãŸã‚ã®ã‚‚ã®ã§ã™ã€‚ 実ã®ã¨ã“ã‚「緊急事態用ã®ãƒ¡ãƒ¢ãƒªã€ã¯ä¸€èˆ¬çš„ã«ç››å¤§ã«æ‚ªå½±éŸ¿ã‚’åŠã¼ã—ã¾ã™ã€‚ スワップを無効ã«ã™ã‚‹ã“ã¨ã¯
Linux Profiling at Netflix
This talk discusses Linux profiling using perf_events (also called "perf") based on Netflix's use of it. It covers how to use perf to get CPU profiling working and overcome common issues. The speaker will give a tour of perf_events features and show how Netflix uses it to analyze performance across their massive Amazon EC2 Linux cloud. They rely on tools like perf for customer satisfaction, cost o
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Ethernetã®å—信処ç†
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多人数ã«ã‚ˆã‚Šæ—¥ã€…改善ãŒåŠ ãˆã‚‰ã‚Œã‚‹Linuxカーãƒãƒ«ã§ã™ãŒã€ãã®ä¸ã«ã¯ã¾ã£ãŸãæ–°ã—ã„機能もã‚ã‚Œã°ã€æ—¢å˜æ©Ÿèƒ½ã‚’æ‹¡å¼µã—ãŸã‚‚ã®ã‚‚ã‚ã‚Šã¾ã™ã€‚本記事ã§ã¯open(2)ã«åŠ ãˆã‚‰ã‚ŒãŸæ–°ãƒ•ãƒ©ã‚°ã«ã¤ã„ã¦å–り上ã’ã¾ã™ã€‚ O_TMPFILEフラグ ---- linux-3.11 2014å¹´9月ã«ãƒªãƒªãƒ¼ã‚¹ã•ã‚ŒãŸlinux-3.11ã§ã¯ã€ãƒ•ã‚¡ã‚¤ãƒ«ã‚ªãƒ¼ãƒ—ン時ã«æŒ‡å®šå¯èƒ½ãªO_TMPFILEフラグãŒè¿½åŠ ã•ã‚Œã¾ã—ãŸã€‚目的ã¯å¾“æ¥ã®mkstemp(3)ã€tmpfile(3)ã¨åŒæ§˜ã§ã™ãŒã€ã‚«ãƒ¼ãƒãƒ«ãƒ¬ãƒ™ãƒ«ã§å¯¾å¿œã™ã‚‹ãŸã‚ã€åŠ¹çŽ‡ã¨ã‚¢ãƒˆãƒŸãƒƒã‚¯æ€§ãŒå¼·åŒ–ã•ã‚Œã¾ã™ã€‚glibcã§ã¯2014å¹´2月ã«ãƒªãƒªãƒ¼ã‚¹ã•ã‚ŒãŸv2.19ã§O_TMPFILEã«å¯¾å¿œã—ã¾ã—ãŸã€‚ 従æ¥ã®mkstemp(3)ファミリã€tmpfile(3)を用ã„ã‚‹å ´åˆã§ã¯ã€ 一æ„ãªï¼ˆã¨æœŸå¾…ã§ãる）ファイルåã®ç”Ÿæˆ ãã®ãƒ•ã‚¡ã‚¤ãƒ«åã§ãƒ•ã‚¡ã‚¤ãƒ«ã‚’作æˆ/オープン ã¨ã„ã†æ‰‹é †ã‚’è¸ã¿ã¾ã™ãŒã€ä¸€æ„性をä¿
Etsukata blog: Docker を支ãˆã‚‹ Linux Kernel ã®æ©Ÿèƒ½ (概è¦ç·¨)
ã¯ã˜ã‚ã« Docker ã¯ã‚³ãƒ³ãƒ†ãƒŠåž‹ä»®æƒ³åŒ–技術を使ã£ã¦OSレベル仮想化を実ç¾ã™ã‚‹ã‚³ãƒ³ãƒ†ãƒŠç®¡ç†ã‚½ãƒ•ãƒˆã‚¦ã‚§ã‚¢ã§ã™ã€‚é¡žä¼¼ã®ã‚³ãƒ³ãƒ†ãƒŠç®¡ç†ã‚½ãƒ•ãƒˆã¨ã—ã¦ã¯ã€Docker ã®ä»–ã«ã‚‚ libvirt〠lxc-tools ãªã©ãŒã‚ã‚Šã¾ã™ãŒã€ Docker ã«ã¯ä»¥ä¸‹ã®å¤§ããªç‰¹å¾´ãŒã‚ã‚Šã¾ã™ã€‚ Infrastructure as Code ã®æ€æƒ³ã«åŸºã¥ãã€ã‚³ãƒ³ãƒ†ãƒŠã‚’コード(Dockerfile) ã§ç®¡ç†ã§ãã‚‹ docker index ã§ã€ã‚³ãƒ³ãƒ†ãƒŠã‚¤ãƒ¡ãƒ¼ã‚¸ã‚’手軽ã«å–å¾—ã€å…±æœ‰ã§ãã‚‹ Docker ã¯ä¸Šè¨˜ã®ã‚ˆã†ãªç‰¹å¾´ã‚’æŒã¤ãŸã‚ã€ã‚¢ãƒ—リケーションã®ãƒãƒ¼ã‚¿ãƒ“リティを大ããå‘上ã•ã›ã‚‹ã“ã¨ãŒã§ãã‚‹ã¨æœŸå¾…ã•ã‚Œã¦ã„ã¾ã™ã€‚ å‚考：Naoya Ito æ° "Dockerアプリケーションã®ãƒãƒ¼ã‚¿ãƒ“リティを考ãˆã‚‹" 大変便利㪠Docker ã§ã™ãŒã€Docker ã«ã‚ˆã‚‹ã‚³ãƒ³ãƒ†ãƒŠç®¡ç†ã¯ã€å®Ÿã¯æ•°å¤šãã® Linux Kernel ã®æ©Ÿèƒ½ã«
Printk Times - eLinux.org
Introduction "Printk-times" is a simple technology which adds some code to the standard kernel printk routine, to output timing data with each message. While crude, this can be used to get an overview of the areas of kernel initialization which take a relatively long time. This feature is used by the Bootup Time Working Group to identify areas of the Linux kernel requiring work to improve bootup t
相手ãŒã„ãªã„ã®ã« ESTABLISHED ã«ãªã£ã¦ã‚‹ TCP ãƒãƒ¼ãƒˆ - tmtms ã®ãƒ¡ãƒ¢
最近 ParallelServer ã¨ã„ã†ãƒ©ã‚¤ãƒ–ラリを作ã£ãŸã®ã§ã™ãŒã€ãã®æœ€ä¸ã«å¥‡å¦™ãªçŠ¶æ…‹ã«ãªã£ã¦ã‚‹ TCP ãƒãƒ¼ãƒˆã‚’見ã¤ã‘ãŸã®ã§ã€ãƒ¡ãƒ¢ã£ã¦ãŠãã¾ã™ã€‚ Ruby ã§ã¯ TCP サーãƒãƒ¼ã¯æ¬¡ã®ã‚ˆã†ãªæ„Ÿã˜ã§ä½œã‚‹ã“ã¨ãŒã§ãã¾ã™ã€‚ãŠæ‰‹è»½ã§ã™ã。 require 'socket' Socket.tcp_server_loop(12345) do |socket, client_addr| socket.puts "Your IP address: #{client_addr.ip_address}" name = socket.gets socket.puts "Hello, #{name}" socket.close end ã“れ㯠12345 ãƒãƒ¼ãƒˆã§ã‚¯ãƒ©ã‚¤ã‚¢ãƒ³ãƒˆã‹ã‚‰ã®æŽ¥ç¶šã‚’å¾…ã¡ã€æŽ¥ç¶šã•ã‚ŒãŸã‚‰ã‚¯ãƒ©ã‚¤ã‚¢ãƒ³ãƒˆã®IPアドレスã¨ã‚¯ãƒ©ã‚¤ã‚¢ãƒ³ãƒˆã‹ã‚‰ã®å…¥åŠ›ã‚’クライアントã«é€ä¿¡ã—ã¦åˆ‡æ–ã™ã‚‹ã ã‘ã®ç°¡å˜ãªãƒ—ãƒã‚°ãƒ©ãƒ
Linuxã§TCP_DEFER_ACCEPTãŒæœ‰åŠ¹ã§ã‚‚accept後readã§ããªã„ç†ç”±
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OOM relation to vm.swappiness=0 in new kernel
I have recently been involved in diagnosing the reasons behind OOM invocation that would kill the MySQL server process. Of course these servers were primarily running MySQL. As such the MySQL server process was the one with the largest amount of memory allocated. But the strange thing was that in all the cases, there was no swapping activity seen and there were enough pages in the page cache. Iron
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CRIU
Welcome to CRIU, a project to implement checkpoint/restore functionality for Linux. Checkpoint/Restore In Userspace, or CRIU (pronounced kree-oo, IPA: /krɪʊ/, Russian: криу), is a Linux software. It can freeze a running container (or an individual application) and checkpoint its state to disk. The data saved can be used to restore the application and run it exactly as it was during the time of the
実行ä¸ãƒ—ãƒã‚»ã‚¹ã® ulimit/rlimit を変更ã™ã‚‹ - Qiita
（bash ã®ã‚³ãƒžãƒ³ãƒ‰ã 㨠ulimit ã ã‘ã©ã‚·ã‚¹ãƒ†ãƒ コールã 㨠get/setrlimit ã ã—ã€ulimit？ rlimit？ ã©ã£ã¡ï¼Ÿï¼‰ ã¯ã˜ã‚ã« ã“ã“↓ã«ã‚る通りã§ã™ãŒã€ã‚«ãƒ¼ãƒãƒ« 2.6.36 以é™ãªã‚‰ prlimit(1) ã§ç°¡å˜ã«ã§ãã¾ã™ï¼ˆprlimit ãŒä½¿ãˆã‚‹ç’°å¢ƒãŒæ‰‹å…ƒã«ãªã‹ã£ãŸã®ã§è©¦ã—ã¦ã„ã¾ã›ã‚“ãŒï¼‰ã€‚ ãれ以å‰ã®ã‚«ãƒ¼ãƒãƒ«ï¼ˆã‚ã‚‹ã„㯠Linux 以外）ãªã‚‰ gdb ã§ã‚¢ã‚¿ãƒƒãƒã—ã¦å¯¾è±¡ãƒ—ãƒã‚»ã‚¹ã§ setrlimit ã‚’ç„¡ç†ã‚„り呼ã³å‡ºã—ã¾ã™ã€‚ debug - setting ulimit on a running process - Super User 手元㫠prlimit ãŒä½¿ãˆã‚‹ç’°å¢ƒãŒãªã‹ã£ãŸã®ã§ gdb を使ã„ã¾ã™ã€‚ ãƒãƒƒãƒã‚’ä½œæˆ gdb ã§ã‚¢ã‚¿ãƒƒãƒã—ãŸçž¬é–“ã«ãƒ—ãƒã‚»ã‚¹ãŒåœæ¢ã—ã¦ã—ã¾ã†ãŸã‚ gdb ã®ã‚³ãƒžãƒ³ãƒ‰ã¯æ‰‹æ‰“ã¡ã›ãšã€åœæ¢æ™‚é–“ã‚’çŸãã™ã‚‹ãŸã‚ã« gdb ã®ã‚³ãƒžãƒ³ãƒ‰ã‚’
Linux Network Namespace ã§éŠã‚“ã§ã¿ã‚‹
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Historical trends in the usage of Linux versions - W3Techs
https://www.static.linuxfound.org/jp_uploads/seminar20070710/LinuxFaultInjection-2.pdf
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