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hiboma id:hiboma

linuxã«é–¢ã™ã‚‹hibomaã®ãƒ–ãƒƒã‚¯ãƒžãƒ¼ã‚¯ (659)

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ãƒˆãƒ©ãƒ–ãƒ«ã‚·ãƒ¥ãƒ¼ãƒ†ã‚£ãƒ³ã‚°ã‹ã‚‰Linuxã‚«ãƒ¼ãƒãƒ«ã«æ½œã‚Šè¾¼ã‚€ â€ å®Ÿéš›ã®ã‚µãƒ¼ãƒ“ã‚¹é‹ç”¨ã§æ·±ã‚ãŸã‚«ãƒ¼ãƒãƒ«ã¸ã®ç†è§£
æœ¬è¨˜äº‹ã¯ã€TechFeed Experts Night#19 ã€œ é”äººã«èžãã€Linuxã‚«ãƒ¼ãƒãƒ«ã‚³ãƒ¼ãƒ‰ã®æ©ãæ–¹ã®ã‚»ãƒƒã‚·ãƒ§ãƒ³æ›¸ãèµ·ã“ã—è¨˜äº‹ã«ãªã‚Šã¾ã™ã€‚ ã‚¤ãƒ™ãƒ³ãƒˆãƒšãƒ¼ã‚¸ã®ã‚¿ã‚¤ãƒ ãƒ†ãƒ¼ãƒ–ãƒ«ã‹ã‚‰ã€ãã®ä»–ã®ã‚»ãƒƒã‚·ãƒ§ãƒ³ã«é–¢ã™ã‚‹è¨˜äº‹ã‚‚ãŠèªã¿é ‚ã‘ã¾ã™ã®ã§ã€ä¸€åº¦ã‚¢ã‚¯ã‚»ã‚¹ã—ã¦ã¿ã¦ãã ã•ã„ã€‚ æœ¬ã‚»ãƒƒã‚·ãƒ§ãƒ³ã®ç™»å£‡è€… ã‚»ãƒƒã‚·ãƒ§ãƒ³å‹•ç”» GMOãƒšãƒ‘ãƒœã®ä¼Šè—¤æ´‹ä¹Ÿã§ã™ã€‚2007å¹´ã‹ã‚‰GMOãƒšãƒ‘ãƒœã«ã¦å‹¤å‹™ã—ã¦ãŠã‚Šã€ãƒ›ã‚¹ãƒ†ã‚£ãƒ³ã‚°ã‚µãƒ¼ãƒ“ã‚¹ã‚„æŠ€è¡“åŸºç›¤ãƒãƒ¼ãƒ ã‚’çµŒã¦ç¾åœ¨ã¯ã‚»ã‚ãƒ¥ãƒªãƒ†ã‚£å¯¾ç–å®¤ã«æ‰€å±žã—ã¦ãŠã‚Šã¾ã™ã€‚ã‚ªãƒ³ãƒ©ã‚¤ãƒ³ã§ã¯TwitterãŠã‚ˆã³Githubã®ã‚¢ã‚«ã‚¦ãƒ³ãƒˆã¨ãƒ–ãƒã‚°ã§æ´»å‹•ã—ã¦ã„ã¾ã™ã€‚ä»Šå›žã¯å®Ÿéš›ã®ã‚µãƒ¼ãƒ“ã‚¹ç’°å¢ƒã§ã®Linuxã‚«ãƒ¼ãƒãƒ«ã®ãƒˆãƒ©ãƒ–ãƒ«ã‚·ãƒ¥ãƒ¼ãƒ†ã‚£ãƒ³ã‚°äº‹ä¾‹ã¨ã¨ã‚‚ã«ã€ã‚«ãƒ¼ãƒãƒ«ã®è©³ç´°èª¿æŸ»ã‚„ã‚³ãƒ¼ãƒ‰ãƒªãƒ¼ãƒ‡ã‚£ãƒ³ã‚°ã®æ–¹æ³•ã‚’ã”ç´¹ä»‹ã—ã¾ã™ã€‚ ç§ã¯Linuxã‚«ãƒ¼ãƒãƒ«ã®ã‚³ãƒŸãƒƒã‚¿ãƒ¼ã‚’ã—ã¦ã„ã‚‹ã‚ã‘ã§ã¯ãªãã€ã¾ãŸLinuxã‚«ãƒ¼ãƒãƒ«ã®é–‹ç™ºæ¥å‹™ã‚‚ã•ã»ã©è¡Œã£ã¦
hiboma 2023/07/26
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Linux

kernel
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ãµã¤ã†ã®Linuxãƒ—ãƒã‚°ãƒ©ãƒŸãƒ³ã‚°-ãƒ—ãƒã‚»ã‚¹ã¨ãƒãƒ¼ãƒ‰ã‚¦ã‚§ã‚¢
ç ”ç©¶ä¼šã®è¼ªè¬›ã§ã‚„ã£ãŸã‚„ã¤ï¼Žå¤šå°‘ãŒã‚“ã°ã£ãŸ&è©•ä¾¡ã‚‚é«˜ã‚ã ã£ãŸã—ä½¿ã„ã¾ã‚ã›ãã†ãªã®ã§ä¸Šã’ã¦ãŠãï¼Ž
hiboma 2020/06/15
linux
ãƒªãƒ³ã‚¯
oss-sec: Linux kernel: FS_IOC_FSSETXATTR will lead to EXT4-fs shut down
hiboma 2018/08/28
linux
ãƒªãƒ³ã‚¯
GitHub - mihic/linux-intel-undervolt: Guide to linux undervolting for Haswell and never Intel CPUs
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hiboma 2018/06/14
wrmsr 0x150 8000001c00000000 ã®ãƒã‚°

kernel

linux
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driver-core: devtmpfs - driver core maintained /dev tmpfs [LWN.net]
[PATCH] driver-core: devtmpfs - driver core maintained /dev tmpfs From: Kay Sievers <kay.sievers@vrfy.org> Subject: driver-core: devtmpfs - driver core maintained /dev tmpfs Devtmpfs lets the kernel create a tmpfs very early at kernel initialization, before any driver core device is registered. Every device with a major/minor will have a device node created in this tmpfs instance. After the rootfs
hiboma 2016/03/16
devtmpfs

linux

kernel
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Limit Linux background flush (dirty pages)
Background flushing on Linux happens when either too much written data is pending (adjustable via /proc/sys/vm/dirty_background_ratio) or a timeout for pending writes is reached (/proc/sys/vm/dirty_expire_centisecs). Unless another limit is being hit (/proc/sys/vm/dirty_ratio), more written data may be cached. Further writes will block. In theory, this should create a background process writing ou
hiboma 2016/02/12
linux

kernel
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https://events.static.linuxfound.org/images/stories/pdf/lcjp2012_wu.pdf
hiboma 2016/02/12
No-I/O dirty throttling

linux

kernel
ãƒªãƒ³ã‚¯
No-I/O dirty throttling [LWN.net]
This article brought to you by LWN subscribersSubscribers to LWN.net made this article â€” and everything that surrounds it â€” possible. If you appreciate our content, please buy a subscription and make the next set of articles possible. "Writeback" is the process of writing dirty pages back to persistent storage, allowing those pages to be reclaimed for other uses. Making writeback work properly has
hiboma 2016/02/12
linux

kernel
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Linux ftrace TCP Retransmit Tracing
Recent posts: 29 Oct 2024 Â» AI Flame Graphs 22 Jul 2024 Â» No More Blue Fridays 24 Mar 2024 Â» Linux Crisis Tools 17 Mar 2024 Â» The Return of the Frame Pointers 10 Mar 2024 Â» eBPF Documentary 28 Apr 2023 Â» eBPF Observability Tools Are Not Security Tools 01 Mar 2023 Â» USENIX SREcon APAC 2022: Computing Performance: What's on the Horizon 17 Feb 2023 Â» USENIX SREcon APAC 2023: CFP 02 May 2022 Â» Brendan
hiboma 2015/11/10
TCP Retransmit

linux

network
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Netstat -s showing (and growing) "packets pruned from receive queue" and "packets collapsed in receive queue"
we are seeing the following: [root@primary data]# netstat -s | grep buffer ; sleep 10 ; netstat -s | grep buffer 20560 packets pruned from receive queue because of socket buffer overrun 997586 packets collapsed in receive queue due to low socket buffer 20587 packets pruned from receive queue because of socket buffer overrun 998646 packets collapsed in receive queue due to low socket buffer [root@p
hiboma 2015/11/10
packets pruned from receive queue

linux

network
ãƒªãƒ³ã‚¯
Riak, Elasticsearch and numad walk into a Red Hat
What starts like a joke is really a serious post about large distributed systems. This is what we run at meltwater - and while there is a lot of fun designing and administering these systems, we run into odd probl ems from time to time. In this case: some well-meant Red Hat memory optimisations interfering with Riak performance. There is a lot of talk around â€œBig Dataâ€ in the industry - and here at
hiboma 2015/09/04
linux

kernel
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é©å‘½ã®æ—¥ã€…ï¼ RHEL6 S390ç”¨ãƒãƒ¥ãƒ¼ãƒ‹ãƒ³ã‚°ãƒ‘ãƒ©ãƒ¡ã‚¿æŽ¨å¥¨å€¤è§£èª¬
RHEL6ã®ãƒ‰ã‚ãƒ¥ãƒ¡ãƒ³ãƒˆãƒšãƒ¼ã‚¸ï¼ˆâ€»ï¼‰ã¿ã¦ãŸã®ã ã‘ã© â€» http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/ Technical Notes: http://docs.redhat.com/docs/en-US/Red_Hat_Enterprise_Linux/6/html-single/Technical_Notes/index.html ã«é¢ç™½ã„ãƒãƒ¥ãƒ¼ãƒ‹ãƒ³ã‚°ãƒ‘ãƒ©ãƒ¡ã‚¿ã®è¨˜è¿°ã‚’ã¿ã¤ã‘ãŸã®ã§è§£èª¬ã—ã¦ã¿ã‚‹ã€‚S390å‘ã‘ã®ãƒãƒ¥ãƒ¼ãƒ‹ãƒ³ã‚°æŽ¨å¥¨å€¤ã®éƒ¨åˆ†ã ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ãƒ¼ System z Performance Some of the default tunables in Red Hat Enterprise Linux 6 are curr
hiboma 2015/09/04
linux

kernel
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Why do forked processes sometimes appear with brackets [] around their name in ps?
On a Linux system a C process is started on boot, which creates a fork of itself. It is not a kernal process or something. In most cases a ps -ef show both processes as expecxted, but sometimes it looks like the following: 1258 root 0:00 myproc 1259 root 0:00 [myproc] i.e. one of the processes surrounded by brackets. According to ps: If the arguments cannot be located (usually because it has not b
hiboma 2015/05/26
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linux
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ãƒ¦ãƒ¼ã‚¶IDã‚’å¤‰æ›´ã™ã‚‹ãƒ—ãƒã‚°ãƒ©ãƒ ã®coreãƒ€ãƒ³ãƒ— - Journal InTime(2014-02-11)
_ ãƒ¦ãƒ¼ã‚¶IDã‚’å¤‰æ›´ã™ã‚‹ãƒ—ãƒã‚°ãƒ©ãƒ ã®coreãƒ€ãƒ³ãƒ— Unixãƒ©ã‚¤ã‚¯ãªOSã§ã¯ã€ãƒ¦ãƒ¼ã‚¶IDã‚’å¤‰æ›´ã™ã‚‹ãƒ—ãƒã‚°ãƒ©ãƒ ã§SEGVãŒç™ºç”Ÿã—ãŸå ´åˆã€ulimitãªã©ã§coreã‚’åãã‚ˆã†ã«è¨å®šã—ã¦ã„ã¦ã‚‚coreãŒåã‹ã‚Œãªã„ã“ã¨ãŒã‚ã‚‹ã€‚ ã“ã‚Œã¯ã‚»ã‚ãƒ¥ãƒªãƒ†ã‚£ä¸Šã®ç†ç”±ã§ã€ä¾‹ãˆã°setuidãƒ—ãƒã‚°ãƒ©ãƒ ã§ã¯ã€ä¸€èˆ¬ãƒ¦ãƒ¼ã‚¶ã«è¦‹ã‚‰ã‚Œã¦ã¯ã¾ãšã„æƒ…å ±ãŒcoreãƒ•ã‚¡ã‚¤ãƒ«ã‹ã‚‰æ¼æ´©ã—ãŸã‚Šã€rootæ¨©é™ã®ãƒ•ã‚¡ã‚¤ãƒ«ã‚’ä¸Šæ›¸ãã—ã¦ã—ã¾ã†ã¨ã„ã£ãŸå•é¡ŒãŒã‚ã‚‹ã®ã§ã€å˜ç´”ã«rootæ¨©é™ã§coreãƒ•ã‚¡ã‚¤ãƒ«ã‚’ä½œæˆã—ã¦ã—ã¾ã†ã“ã¨ã¯å¥½ã¾ã—ããªã„ã€‚ ã“ã®ãŸã‚ã€setuidãƒ—ãƒã‚°ãƒ©ãƒ ã‚„ã€seteuid(2)ãªã©ã§ãƒ¦ãƒ¼ã‚¶ID/ã‚°ãƒ«ãƒ¼ãƒ—IDã‚’å¤‰æ›´ã™ã‚‹ãƒ—ãƒã‚°ãƒ©ãƒ ã¯ã€ãƒ‡ãƒ•ã‚©ãƒ«ãƒˆã§ã¯coreã‚’åã‹ãªã„ã‚ˆã†ã«ãªã£ã¦ã„ã‚‹ã€‚ ã“ã®å‹•ä½œã¯é€šå¸¸ã¯å•é¡Œãªã„ãŒã€ãƒ‡ãƒãƒƒã‚°ã®éš›ã«ä¸ä¾¿ãªã®ã§ã€Linuxãªã©ã§ã¯è¨å®šã§å‹•ä½œã‚’å¤‰ãˆã‚‰ã‚Œã‚‹ã‚ˆã†ã«ãªã£ã¦ã„ã‚‹ã€‚ ã‚°ãƒãƒ¼ãƒãƒ«ãªè¨å®š Linuxã®å ´åˆã¯
hiboma 2015/04/02
fs.suid_dumpable

linux
ãƒªãƒ³ã‚¯
KMC Staff Blog:ç°¡å˜ãªLinuxã‚«ãƒ¼ãƒãƒ«ã®ãƒ—ãƒãƒ•ã‚¡ã‚¤ãƒ« (readprofile)
2011å¹´10æœˆ19æ—¥ ç°¡å˜ãªLinuxã‚«ãƒ¼ãƒãƒ«ã®ãƒ—ãƒãƒ•ã‚¡ã‚¤ãƒ« (readprofile) Linuxã‚«ãƒ¼ãƒãƒ«ã®ã‚¿ã‚¤ãƒžãƒ¼å‰²ã‚Šè¾¼ã¿ã®ã¨ã“ã‚ã®ã‚½ãƒ¼ã‚¹ã‚’è¦‹ã¦ã„ãŸã‚‰ã€ç°¡å˜ãªã—ãã¿ã®ãƒ—ãƒãƒ•ã‚¡ã‚¤ãƒ©ãŒçµ„ã¿è¾¼ã¾ã‚Œã¦ã„ã‚‹ã®ã‚’è¦‹ã¤ã‘ã¾ã—ãŸã€‚ã“ã‚Œã¯ã‚¿ã‚¤ãƒžãƒ¼å‰²ã‚Šè¾¼ã¿ã®ã¨ã“ã‚ã§ãƒ—ãƒã‚°ãƒ©ãƒ ã‚«ã‚¦ãƒ³ã‚¿ãŒã©ã“ã‚’æŒ‡ã—ã¦ã„ãŸã‹ã‚’ç´¯è¨ˆã—ã¦ã„ãã€readprofileã¨ã„ã†ãƒ„ãƒ¼ãƒ«ã§ãã®çµæžœã‚’è¦‹ã‚‹ã“ã¨ãŒã§ãã¾ã™ã€‚ ã“ã®ãƒ—ãƒãƒ•ã‚¡ã‚¤ãƒ©ã¯CONFIG_PROFILING=y ã§ã‚«ãƒ¼ãƒãƒ«ã‚’ãƒ“ãƒ«ãƒ‰ã™ã‚‹ã ã‘ã§ä½¿ã†ã“ã¨ãŒã§ãã¾ã™ã€‚ Ubuntu 10.04 (x86_64)ã®ã‚«ãƒ¼ãƒãƒ«ã¯ãã®æ¡ä»¶ã§ãƒ“ãƒ«ãƒ‰ã•ã‚Œã¦ã„ã‚‹ã®ã§ã™ãã«è©¦ã™ã“ã¨ãŒã§ãã¾ã—ãŸã€‚ ãƒ—ãƒãƒ•ã‚¡ã‚¤ãƒ©ã®æº–å‚™ rootã§ # echo 2 > /sys/kernel/profiling ã¾ãŸã¯ $ sudo sh -c "echo 2 > /sys/kernel/profiling" (ã“ã®'
hiboma 2015/03/18
linux

kernel
ãƒªãƒ³ã‚¯
nss-myhostnameã§ã€è‡ªãƒ›ã‚¹ãƒˆåã‚’å¸¸ã«å¼•ã‘ã‚‹ã‚ˆã†ã«ã™ã‚‹ - ãƒ–ãƒã‚° - ãƒ¯ãƒ«ãƒ–ãƒªãƒƒã‚¯ã‚¹æ ªå¼ä¼šç¤¾
ã“ã®è¨˜äº‹ã¯ STBBS.NET BLOGã‹ã‚‰ç§»å‹•ã•ã‚ŒãŸã‚‚ã®ã§ã™ Javaã§è‡ªãƒ›ã‚¹ãƒˆã®åå‰ã‚’èª¿ã¹ã‚ˆã†ã¨ã—ãŸã‚‰ã€ä¸‹è¨˜ã®ã‚ˆã†ã«ãªã‚‹ã€‚ java.net.InetAddress.getLocalHost().getHostName() ã®ã ãŒã€getLocalHost()ã®å‘¼ã³å‡ºã—æ™‚ç‚¹ã§ UnknownHostException ãŒå‡ºã¦ã—ã¾ã†å ´åˆãŒã‚ã‚‹ã€‚ Javaãƒ©ãƒ³ã‚¿ã‚¤ãƒ ã¯ getLocalHost()ã®ä¸ã§ã¾ãšè‡ªãƒ›ã‚¹ãƒˆåã‚’èª¿ã¹ãŸå¾Œã«ãã®IPã‚¢ãƒ‰ãƒ¬ã‚¹ã‚’è§£æ±ºã—ã‚ˆã†ã¨ã™ã‚‹ã®ã ãŒã€ã™ã‚‹ã¨ãƒ›ã‚¹ãƒˆåã‹ã‚‰IPã‚¢ãƒ‰ãƒ¬ã‚¹ã‚’è§£æ±ºã§ããªã„å ´åˆã«ã¯å½“ç„¶ã“ã®ä¾‹å¤–ãŒé€å‡ºã•ã‚Œã‚‹ã“ã¨ã«ãªã‚‹ã€‚ ãƒ›ã‚¹ãƒˆåã‹ã‚‰IPã‚¢ãƒ‰ãƒ¬ã‚¹ã‚’å¼•ã‘ãªã„ç†ç”±ã‚’ã„ã‚ã„ã‚ç«¯æŠ˜ã£ã¦ä¸€è¨€ã§ã„ã†ã¨ã€/etc/hosts ã«è¼‰ã£ã¦ã„ãªã„ã‹ã‚‰ã ã€‚ OSã®ã‚¤ãƒ³ã‚¹ãƒˆãƒ¼ãƒ©ãŒæ°—ã‚’åˆ©ã‹ã›ã¦ /etc/hostsã«ãƒ›ã‚¹ãƒˆåã‚’è¿½è¨˜ã—ã¦ãã‚Œã¦ã„ã‚Œã°ã“ã†ã„ã†å•é¡Œã¯èµ·ã“ã‚‰ãªã„ã®ã ãŒã€ã
hiboma 2015/02/12
ã¸ãƒ¼

linux
ãƒªãƒ³ã‚¯
CentOS/SSD - maruko2 Note.
CentOS/SSD æä¾›ï¼šmaruko2 Note. < CentOS ç§»å‹•ï¼š æ¡ˆå†…, æ¤œç´¢ RHEL 6 (CentOS 6) ã¯ã€ext4 ãƒ•ã‚¡ã‚¤ãƒ«ã‚·ã‚¹ãƒ†ãƒ ã§ discard ã‚’ã‚µãƒãƒ¼ãƒˆã—ã¦ã„ã‚‹ã€‚ãŸã ã—ã€æœ‰åŠ¹ã«ãªã£ã¦ã„ãªã„ã®ã§ãƒžã‚¦ãƒ³ãƒˆã‚ªãƒ—ã‚·ãƒ§ãƒ³ã¨ã—ã¦ discard ã‚’æŒ‡å®šã™ã‚‹å¿…è¦ãŒã‚ã‚‹ã€‚ At present, ext4 is the only fully-supported file system that supports discard. To enable discard commands on a device, use the mount option discard. For example, to mount /dev/sda2 to /mnt with discard enabled, run: mount -t ext4 -o discard /dev/sda2
hiboma 2014/12/10
"Linux swap ã¯ discard ã‚’æœ‰åŠ¹ã«ã—ã¦ã„ã‚‹ãƒ‡ãƒã‚¤ã‚¹ã§ã€discard ã‚³ãƒžãƒ³ãƒ‰ã‚’åˆ©ç”¨ã—ã¾ã™ã€‚swap ã« discard ã‚’æœ‰åŠ¹ã«ã™ã‚‹ã‚ˆã†ãªã‚ªãƒ—ã‚·ãƒ§ãƒ³ã¯ã‚ã‚Šã¾ã›ã‚“ã€‚"

linux
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ãƒ—ãƒãƒ•ã‚¡ã‚¤ãƒ©ã®ã—ãã¿ steps to phantasien t(2007-08-23)
UNIX åå‘æ–‡æ›¸ artu ã®ä¸ã§ "Measure Before Optimizing" ã¨èª¬ã Raymond ã¯, åŒæ™‚ã«ãƒ—ãƒãƒ•ã‚¡ã‚¤ãƒ©ã®è¨ˆæ¸¬æ©Ÿæ§‹ (instrumentation) ãŒã‚‚ãŸã‚‰ã™ãƒŽã‚¤ã‚ºã«ã¤ã„ã¦æ³¨æ„ã‚’ä¿ƒã—ã¦ã„ã‚‹. ç§ã®ãƒ—ãƒãƒ•ã‚¡ã‚¤ãƒ©ä¿¡ä»°ã«ä¸å®‰ãŒç¿³ã‚’è½ã¨ã™. gprof ãƒŽã‚¤ã‚ºã¯ã•ã¦ãŠã, ãã‚‚ãã‚‚ãƒ—ãƒãƒ•ã‚¡ã‚¤ãƒ©ã¯ã©ã‚“ãªä»•çµ„ã¿ã§é€Ÿåº¦ã‚’æ¸¬ã£ã¦ã„ã‚‹ã‚“ã ã‚ã†. gprof ã®ãƒžãƒ‹ãƒ¥ã‚¢ãƒ« ã«ã‚ˆã‚‹ã¨, GNU ä¸€æ—ã®ãƒ—ãƒãƒ•ã‚¡ã‚¤ãƒ©ã¯æ¬¡ã®ã‚ˆã†ã«å®Ÿè£…ã•ã‚Œã¦ã„ã‚‹: ã¾ãš "-pg" ã‚ªãƒ—ã‚·ãƒ§ãƒ³ã¤ãã® gcc ã§ã‚½ãƒ¼ã‚¹ã‚’ã‚³ãƒ³ãƒ‘ã‚¤ãƒ«ã™ã‚‹. ã“ã®æŒ‡ç¤ºã‚’å—ã‘ãŸã‚³ãƒ³ãƒ‘ã‚¤ãƒ©ã¯å„é–¢æ•°ã®å†’é ã« "mcount" ã¨ã„ã†åå‰ã®é–¢æ•°å‘¼å‡ºã—ã‚’åŠ ãˆã‚‹. ãƒªãƒ³ã‚¯ã™ã‚‹ C ã®ãƒ©ãƒ³ã‚¿ã‚¤ãƒ ã‚‚å°‚ç”¨ãƒãƒ¼ã‚¸ãƒ§ãƒ³ (gcrt0.o) ã«å·®ã—æ›¿ã‚ã‚‹. ã“ã®ãƒ©ãƒ³ã‚¿ã‚¤ãƒ ã¯è£ã§ profil() é–¢æ•°ã‚’ä½¿ã„ã‚¿ã‚¤ãƒžã‚’ä»•æŽ›ã‘ã‚‹. ãã®ã‚¿ã‚¤ãƒžã¯ç™º
hiboma 2014/10/28
linux
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ftraceã«ã¤ã„ã¦èª¿ã¹ã‚‹(å‰å›žã‹ã‚‰ã®ç¶šã) - akachochinã®æ—¥è¨˜
ftraceã®ä»•çµ„ã¿ã‚’èª¿ã¹ã‚‹ãŸã‚ã«ã‚°ã‚°ã£ã¦ã„ãŸã‚‰ã€http://bit.ly/9cGM9dã€€ã¨ã„ã†è«–æ–‡ã‚’ç™ºè¦‹ã€‚ æ—©é€Ÿèªã‚“ã§ã¿ã‚‹ã€‚ ftraceã¯gcc ã® -pgã‚ªãƒ—ã‚·ãƒ§ãƒ³ã‚’åˆ©ç”¨ã—ã¦ã€é–¢æ•°ã®å…¥ã‚Šå£ã§mcount()ã¨ã„ã†é–¢æ•°ã‚’ã‚³ãƒ¼ãƒ«ã™ã‚‹ã‚ˆã†ã«ã—ã¦ã„ã‚‹ã€‚ (-pgã¯ãƒ—ãƒãƒ•ã‚¡ã‚¤ãƒ©ãªã©ã®ãŸã‚ã«ç”¨æ„ã•ã‚ŒãŸã‚ªãƒ—ã‚·ãƒ§ãƒ³ã§ã€ã“ã®ã‚ªãƒ—ã‚·ãƒ§ãƒ³ã§ã‚³ãƒ³ãƒ‘ã‚¤ãƒ«ã•ã‚ŒãŸé–¢æ•°ã¯å…¥ã‚Šå£ã§mcount()ã¨ã„ã†é–¢æ•°ã‚’å‘¼ã¶ã‚ˆã†ã«ãªã‚‹ã‚‰ã—ã„) ãã—ã¦ã€å„CPUã‚¢ãƒ¼ã‚ãƒ†ã‚¯ãƒãƒ£ã”ã¨ã«å®šç¾©ã•ã‚ŒãŸmcount()ã®ä¸ã§ã‚¹ã‚¿ãƒƒã‚¯ã‚’å¼„ã‚Šã€mcount()å‘¼ã³å‡ºã—å…ƒã®é–¢æ•°ãŒçµ‚äº†ã—ãŸæ™‚ã«æˆ»ã‚‹ã¹ããƒªã‚¿ãƒ¼ãƒ³ã‚¢ãƒ‰ãƒ¬ã‚¹ã‚’æ›¸ãæ›ãˆã¦ãŠãã€‚ ã“ã‚Œã«ã‚ˆã‚Šã€é–¢æ•°çµ‚äº†æ™‚ã«åˆ¥é€”æ¸¬å®šç”¨ã®é–¢æ•°ãŒã‚³ãƒ¼ãƒ«ã•ã‚Œã‚‹ã“ã¨ã«ãªã‚‹ã€‚ æ—©é€Ÿä»•çµ„ã¿ã‚’å®Ÿè£…ã§è¿½ã„ã‹ã‘ã‚‹ã¹ãã€mipsã‚¢ãƒ¼ã‚ãƒ†ã‚¯ãƒãƒ£ã‚’é¸ã‚“ã§èªã‚“ã§è¦‹ãŸã€‚ 98 NESTED(_mcount, PT_SIZE, ra) 99
hiboma 2014/10/28
ftrace, -pg, mcount

linux

gcc

kernel
ãƒªãƒ³ã‚¯
Quotes of the week [LWN.net]
hiboma 2014/10/09
EINVAL -> __LINE__

linux

kernel
ãƒªãƒ³ã‚¯
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