{"id":431,"date":"2025-05-19T23:39:49","date_gmt":"2025-05-19T23:39:49","guid":{"rendered":"https:\/\/boochlin.com\/?p=431"},"modified":"2025-06-10T08:06:37","modified_gmt":"2025-06-10T08:06:37","slug":"android-%e7%88%9b%e8%a3%9d%e7%bd%ae%e6%83%b3%e8%b7%91%e4%ba%ba%e8%87%89%e8%be%a8%e8%ad%984-%e8%a8%98%e6%86%b6%e9%ab%94%e6%8e%a7%e5%a0%b4%e5%b8%ablmkd","status":"publish","type":"post","link":"https:\/\/boochlin.com\/?p=431","title":{"rendered":"Android \u721b\u88dd\u7f6e\u60f3\u8dd1\u4eba\u81c9\u8fa8\u8b584-\u8a18\u61b6\u9ad4\u63a7\u5834\u5e2bLMKD"},"content":{"rendered":"\n<p><img decoding=\"async\" width=\"960px;\" height=\"494px;\" src=\"https:\/\/lh7-rt.googleusercontent.com\/slidesz\/AGV_vUdzDPdHhBDxfveZWnWNdlOd01rnkLSEOUMWG5FCqNdT0xGepYZQHGsSdij1EP-tTi-6zjlgN4EgxsAioP-j5SVhVvSUdKm8i2Q3Cbba-S8mSj1StVmP5vSNwXn2RD4GeudUztTmzTXH6rLyW_mtIbx6B7o3_PY=s2048?key=Te3C0G-QmQixACYoDXXiOg\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u300a\u6bba\u7684\u4e0d\u662f Process\uff0c\u662f\u6211\u7684\u5e79\u8a71\u6642\u9593\u300b<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">\u3010\u4f60\u4ee5\u70ba\u95dc\u6389\u5e7e\u500b\u6c92\u7528\u7684 system service \u5c31\u89e3\u6c7a\u4e86\uff1f\u3011<\/h3>\n\n\n\n<p>Android \u672c\u4f86\u5c31\u6709\u4e00\u5957\u300c\u5feb\u7206\u4e86\u6211\u4f86\u6bba\u4eba\u300d\u7684\u5167\u5efa\u6a5f\u5236\uff0c\u540d\u70ba\uff1a<\/p>\n\n\n\n<p class=\"has-large-font-size\"><strong>Low-Memory Killer Daemon<\/strong><\/p>\n\n\n\n<p>\u6211\u5011\u628a\u9019\u5e7e\u500b\u5b57\u5206\u958b\u4f86\u770b\uff0c Low- Memory \uff0cKiller\uff0cDaemon<\/p>\n\n\n\n<p><strong>Low-Memory \u4f4e\u8a18\u61b6\u9ad4<\/strong>\uff0c\u9996\u5148\u6211\u5011\u8981\u5b9a\u7fa9\uff0c\u5565\u7c73\u662f\u4f4e\u8a18\u61b6\u9ad4\uff0c\u600e\u6a23\u7684\u60c5\u6cc1\u53eb\u505a\u4f4e\u8a18\u61b6\u9ad4\uff0c\u8981\u591a\u4f4e\u624d\u7b97\uff0c\u6709\u6c92\u6709\u9ad8\u6548\u7684\u8a0a\u865f\u53ef\u4ee5\u77e5\u9053\u73fe\u5728\u7684\u72c0\u6cc1\uff0c\u5982\u679c\u6709\uff0c\u90a3\u80fd\u5373\u6642\u76e3\u6e2c\u55ce\uff1f\u6703\u8017\u8cc7\u6e90\u55ce\uff1f<\/p>\n\n\n\n<p><strong>Killer \u6bba\u624b<\/strong>\uff0c\u6bba\u624b\u8981\u6bba\u8ab0\uff0c\u4e5f\u5c31\u662f\u8981 kill process\uff0c\u90a3\u8ab0\u8a72\u88ab\u6bba\uff0c\u6709\u6c92\u6709\u4e00\u500b\u660e\u78ba\u6307\u6a19\uff0c\u5982\u679c\u6bba\u4e00\u500b\u4e0d\u5920\uff0c\u90a3\u8981\u6bba\u5e7e\u500b\uff1f\u6709\u6c92\u6709\u9806\u5e8f\uff1f\u600e\u9ebc\u6bba\uff1f\u7232\u4f55\u8981\u6bba\uff1f<\/p>\n\n\n\n<p><strong>Daemon\uff0c\u5b88\u8b77\u795e<\/strong>\u3001\u60e1\u9b54\uff1f\u5176\u5be6\u9019\u500b\u6c92\u5fc5\u8981\u53bb\u6df1\u7a76\uff0c\u6211\u53ea\u662f\u60f3\u8981\u5206\u4eab\u9ce5\u54e5\u8aaa\u7684<\/p>\n\n\n\n<blockquote class=\"wp-block-quote\">\n<p>\u4f60\u4e0d\u5fc5\u53bb\u5340\u5206\u4ec0\u9ebc\u662f daemon \u8207 service \uff01\u4e8b\u5be6\u4e0a\uff0c\u4f60\u53ef\u4ee5\u5c07\u9019\u5169\u8005\u8996\u70ba\u76f8\u540c\uff01\u56e0\u70ba\u9054\u6210\u67d0\u500b\u670d\u52d9\u662f\u9700\u8981\u4e00\u652f daemon \u5728\u80cc\u666f\u4e2d\u904b\u4f5c\uff0c \u6c92\u6709\u9019\u652f daemon \u5c31\u4e0d\u6703\u6709 service \uff01\u6240\u4ee5\u4e0d\u9700\u8981\u5206\u7684\u592a\u6e05\u695a\u5566\uff01<\/p>\n<\/blockquote>\n\n\n\n<p>\u4e0a\u9762\u5e7e\u500b\u554f\u984c\uff0c\u90fd\u662f\u5e0c\u671b\u5f97\u5230\u4e00\u500b\u6548\u679c\uff0c\u5c31\u662f\u6c92\u6709\u8a18\u61b6\u9ad4\u7684\u6642\u5f8c\uff0c\u6211\u5011\u8981\u5f9e\u54ea\u6316\u51fa\u4e00\u4e9b\u8a18\u61b6\u9ad4\u53ef\u4ee5\u7528\uff1f<\/p>\n\n\n\n<!--more-->\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e00\u822c\u624b\u6a5f\u600e\u9ebc\u8655\u7406\u8a18\u61b6\u9ad4\uff1f<\/h2>\n\n\n\n<p>\u7c21\u55ae\u8b1b\uff1a\u76e1\u91cf\u4e0d\u6bba\uff0c\u80cc\u666f\u591a\u7559\u9ede\uff0c\u5207 App \u9806\u4e00\u9ede\uff0c\u7528\u6236\u9ad4\u9a57\u6bd4\u8f03\u597d\u3002<\/p>\n\n\n\n<p><strong>\u4f46\u8a18\u5f97\u6211\u5011\u524d\u9762\u63d0\u5230\u7684\uff0c\u4efb\u4f55\u7684\u8abf\u6559\u90fd\u9700\u8981\u57fa\u65bc\u4f7f\u7528\u60c5\u5883\uff0c\u6211\u5011\u8a18\u61b6\u9ad4\u4e0d\u5920\uff0c\u4f46\u6211\u5011\u4e0d\u662f\u624b\u6a5f\uff0c\u6211\u5011\u662f\u4e00\u53f0\u4eba\u81c9\u8fa8\u8b58\u6a5f\uff0c\u6211\u5011\u53ea\u9700\u8981\u8dd1\u9019\u500b\u524d\u53f0\u7684\u7a0b\u5f0f\uff0c\u4e0d\u7528\u5207\u63db APP\uff0c<\/strong><\/p>\n\n\n\n<p>\u4e0a\u9762\u9019\u6bb5\u662f\u4e00\u500b\u91cd\u9ede\uff0c\u4f46\u6211\u5148\u56de\u5230 LMKD \u7684\u7b2c\u4e00\u500b\u91cd\u9ede \u201c<strong>\u76e3\u63a7\u8a18\u61b6\u9ad4\u8cc7\u6e90<\/strong>\u201d\uff0c\u5169\u500b\u8981\u6c42<\/p>\n\n\n\n<ol>\n<li>\u6b63\u78ba\uff0c\u964d\u4f4e\u8aa4\u5831<\/li>\n\n\n\n<li>\u5373\u6642\u4f46\u4e0d\u5403\u8cc7\u6e90<\/li>\n<\/ol>\n\n\n\n<p>\u7b2c\u4e8c\u500b\u91cd\u9ede\u662f\u201c\u6c7a\u5b9a\u6bba\u8ab0\uff1f\u201d<\/p>\n\n\n\n<ol>\n<li>\u914d\u7f6e\u5f48\u6027<\/li>\n\n\n\n<li>\u66f4\u9069\u5408 Android \u88dd\u7f6e<\/li>\n<\/ol>\n\n\n\n<p>\u6211\u9019\u908a\u7a0d\u5fae\u5e36\u9ede\u6b77\u53f2\uff0c\u56e0\u70ba\u5728\u6211\u904e\u53bb\u5927\u90e8\u5206\u7684\u5c08\u6848\u90fd\u6709\u770b\u5230\u9019\u5169\u7a2e\u76f8\u4f3c\u7684\u8a18\u61b6\u9ad4\u7ba1\u7406\u5de5\u5177\uff0c\u751a\u81f3\u6211\u5728\u8655\u7406android 10\u7684\u6642\u5019\u9084\u6709\u770b\u5230\uff0c\u8b93\u6211\u975e\u5e38\u6df7\u4e82\uff0c\u6700\u65e9\u6211\u4ee5\u70ba\u662f\u540c\u4e00\u6642\u9593\u53ea\u6703\u6709\u4e00\u7a2e\uff0c\u4f46\u5176\u5be6\u5e38\u5e38\u6709\u4f75\u7528\u7684\u60c5\u6cc1<\/p>\n\n\n\n<ol>\n<li>In-kernel Low Memory Killer<\/li>\n\n\n\n<li>Userspace LMKd\uff08Low Memory Killer daemon\uff09<\/li>\n<\/ol>\n\n\n\n<p>\u773e\u6240\u9031\u77e5\uff0cAndroid base on Linux\uff0c\u90a3\u9019\u7a2e\u8a18\u61b6\u9ad4\u4e0d\u8db3\u7684\u554f\u984c\uff0c\u600e\u9ebc\u53ef\u80fdLinux\u6c92\u6709\u5c08\u9580\u8655\u7406\u7684\u55ae\u4f4d\uff0c\u751a\u81f3\u540d\u7a31\u76f8\u7576\u76f4\u767d <\/p>\n\n\n\n<ul>\n<li>0. <strong>OOM Killer\uff08Out-of-Memory Killer\uff09<\/strong><\/li>\n<\/ul>\n\n\n\n<p>\u90a3\u70ba\u4f55 android \u537b\u4e0d\u7e7c\u7e8c\u6cbf\u7528\u5462\uff1f<\/p>\n\n\n\n<p>\u7c21\u55ae\u4f86\u8aaa \u624b\u6a5f\u7b49 Edge device \u901a\u5e38\u8a18\u61b6\u9ad4\u90fd\u76f8\u5c0d\u5c11\u5f88\u591a\uff0c\u66f4\u4f55\u6cc1\u65e9\u671f\u751a\u81f3\u90fd\u4e0d\u5230 512 mb \uff0c\u800c OOM Killer \u7684\u76e3\u63a7\u8a18\u61b6\u9ad4\u8cc7\u6e90\u662f\u76f4\u63a5\u6839\u64da\u751a\u65bc\u591a\u5c11\u53ef\u7528\u8a18\u61b6\u9ad4\uff0c\u555f\u52d5\uff0c\u9019\u6a23\u7684\u65b9\u5f0f\u6703\u8b93\u4f4e\u8a18\u61b6\u9ad4\u88dd\u7f6e\u4f86\u4e0d\u53ca\u53cd\u61c9\uff0c\u57fa\u672c\u4e0a\u5c31\u6703\u9032\u5165\u5d29\u6f70\u4e86\uff0c\u9019\u500b\u57fa\u672c\u4e0a\u5c31\u4e0d\u7b26\u5408\u7b2c\u4e8c\u9ede <strong>\u300e\u5373\u6642\u300f<\/strong>\uff0c\u52a0\u4e0a\u5c0d\u65bc\u8981 kill \u7684\u5c0d\u8c61\u914d\u7f6e\u4e0a\u4e5f\u4e0d\u5920\u5f48\u6027\uff0c\u662f\u63a1\u7528\u901a\u7528\u7684 <strong>oom_score<\/strong> \uff0c\u9019\u500b\u5206\u6578\u662f\u8003\u616e\u7cfb\u7d71\u7a69\u5b9a\u5ea6\u70ba\u4e3b\u7684\uff0c\u4e26\u975e\u6839\u64da\u4f7f\u7528\u8005\u9ad4\u9a57\u3002<\/p>\n\n\n\n<figure class=\"wp-block-pullquote\"><blockquote><p><a href=\"https:\/\/blog.csdn.net\/u010278923\/article\/details\/105688107\">https:\/\/blog.csdn.net\/u010278923\/article\/details\/105688107<\/a><br>oom_score = (RSS + Page tables + Swap)\/ physical + Swap <\/p><cite>\u57fa\u672c\u4e0a\u8ab0\u5403\u5f97\u5f97\u591a\u5c31\u6bba\u8ab0<\/cite><\/blockquote><\/figure>\n\n\n\n<p>\u524d\u50b3\u7d42\u65bc\u7d50\u675f\u4e86\uff0cOOM killer \u660e\u986f\u7684\u4e0d\u8db3\uff0c Android \u6700\u65e9\u5c31\u8a2d\u8a08\u51fa\u4e86 In-kernel LMK\uff0c\u9996\u5148\u60f3\u6539\u5584\u7684\u5c31\u662f oom_score \u56e0\u6b64\u63d0\u51fa &nbsp;<a href=\"https:\/\/android.googlesource.com\/platform\/system\/memory\/lmkd\/+\/master\/README.md\">oom_adj_score<\/a> \u503c\u8f03\u4f4e\u7684\u7a0b\u5f0f\u5177\u6709\u8f03\u9ad8\u7684\u512a\u5148\u9806\u5e8f\uff0c\u4e26\u4e14\u4e0d\u592a\u53ef\u80fd\u88ab\u7d42\u6b62\uff0c\u4e26\u63d0\u51fa\u4e86\u524d\u666f\u3001\u53ef\u898b\u3001\u670d\u52d9\u3001\u80cc\u666f\u3001\u7a7a \u4e94\u7a2e\u60c5\u6cc1\u66f4\u9069\u5408 Edge device \u7684\u4f7f\u7528\u9019\u60c5\u5883\uff0c\u5728\u914d\u7f6e\u4e0a\u4e5f\u63d0\u51fa minfree \u65b9\u4fbf\u4fee\u6539\u512a\u5148\u7d1a<\/p>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><a href=\"https:\/\/boochlin.com\/wp-content\/uploads\/2025\/05\/image.png\"><img fetchpriority=\"high\" decoding=\"async\" width=\"971\" height=\"1024\" src=\"https:\/\/boochlin.com\/wp-content\/uploads\/2025\/05\/image-971x1024.png\" alt=\"\" class=\"wp-image-495\" style=\"width:336px;height:auto\" srcset=\"https:\/\/boochlin.com\/wp-content\/uploads\/2025\/05\/image-971x1024.png 971w, https:\/\/boochlin.com\/wp-content\/uploads\/2025\/05\/image-285x300.png 285w, https:\/\/boochlin.com\/wp-content\/uploads\/2025\/05\/image-768x810.png 768w, https:\/\/boochlin.com\/wp-content\/uploads\/2025\/05\/image.png 1142w\" sizes=\"(max-width: 971px) 100vw, 971px\" \/><\/a><\/figure><\/div>\n\n\n<p>\u4f46\u662f\u9019\u500b\u7248\u672c\u9084\u662f\u6709\u8a31\u591a\u5148\u5929\u9650\u5236<\/p>\n\n\n\n<ol>\n<li><strong>\u4f4e RAM \u88dd\u7f6e\u7684\u6548\u80fd\u554f\u984c<\/strong>\uff1a\n<ul>\n<li>\u5373\u4f7f\u5728\u4f4e\u8a18\u61b6\u9ad4\u88dd\u7f6e\u4e0a\u9032\u884c\u7a4d\u6975\u7684 LMK \u8a2d\u5b9a\u8abf\u6574\uff0c\u7576\u8655\u7406\u5305\u542b\u5927\u578b\u6a94\u6848\u652f\u63f4\u7684\u6709\u6548\u9801\u9762\u5feb\u53d6\u7684\u5de5\u4f5c\u8ca0\u8f09\u6642\uff0c\u7cfb\u7d71\u4ecd\u53ef\u80fd\u8868\u73fe\u4e0d\u4f73\uff0c\u5c0e\u81f4\u6548\u80fd\u4e0b\u964d\u4e14\u7121\u6cd5\u6709\u6548\u7d42\u6b62\u9032\u7a0b\u3002\u200b\uff08\u4e0d\u7b26\u5408\u5373\u6642\u4e14\u6e96\u78ba\u8981\u4ef6\uff0c\u800c\u4e14\u641e\u8d85\u4e45\uff09<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u8a2d\u8a08\u50f5\u786c\u5c0e\u81f4\u5ba2\u88fd\u5316\u9700\u6c42<\/strong>\uff1a\n<ul>\n<li>\u7531\u65bc LMK \u7684\u8a2d\u8a08\u8f03\u70ba\u50f5\u786c\uff0c\u88dd\u7f6e\u88fd\u9020\u5546\u901a\u5e38\u9700\u8981\u81ea\u8a02\u9a45\u52d5\u7a0b\u5f0f\u4ee5\u9069\u61c9\u7279\u5b9a\u7684\u786c\u9ad4\u548c\u8edf\u9ad4\u914d\u7f6e\uff0c\u589e\u52a0\u4e86\u958b\u767c\u548c\u7dad\u8b77\u7684\u8907\u96dc\u6027\u3002\u200b\uff08\u4e0d\u7b26\u5408\u5f48\u6027\u914d\u7f6e\uff09<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>\u8207 Slab Shrinker API \u7684\u6574\u5408\u6548\u7387\u4f4e\u4e0b<\/strong>\uff1a\n<ul>\n<li>LMK \u9a45\u52d5\u7a0b\u5f0f\u9023\u7d50\u81f3 Slab Shrinker API\uff0c\u4f46\u8a72 API \u4e26\u975e\u8a2d\u8a08\u7528\u65bc\u57f7\u884c\u5982\u641c\u5c0b\u548c\u7d42\u6b62\u9032\u7a0b\u7b49\u91cd\u5ea6\u4f5c\u696d\uff0c\u9019\u53ef\u80fd\u5c0e\u81f4 <code>vmscan<\/code> \u7a0b\u5e8f\u7684\u901f\u5ea6\u8b8a\u6162\uff0c\u5f71\u97ff\u6574\u9ad4\u7cfb\u7d71\u6548\u80fd\u3002\uff08\u4e0d\u7b26\u5408\u5373\u6642\u4e14\u6e96\u78ba\u8981\u4ef6\uff09<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n<p>\u597d\u5566\uff0c\u6211\u626f\u5230\u9019\u908a\u4e5f\u662f\u6709\u9ede\u7d2f\u4e86\uff0cIn-kernel LMK \u6bd4\u8d77OOM killer\u6709\u660e\u986f\u7684\u9032\u6b65\uff0c\u4f46\u9084\u662f\u4e0d\u5920\uff0c\u4e0d\u7b26\u5408\u4e0a\u9762\u63d0\u5230\u7684\u91cd\u9ede 1. \u6b63\u78ba\u4e14\u5373\u6642(vmscan \u642d\u914d slab shrinker \u4e0d\u5920\u529b)\uff0c\u4ee5\u53ca\u4e0d\u5920\u5f48\u6027\u7684\u914d\u7f6e\uff08\u56e0\u70ba\u9084\u662f\u4f9d\u8cf4\u5e7e\u4e4e\u5beb\u6b7b\u7684kernel driver\uff09<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Userspace LMKD \u767b\u5834\uff1a\u7b56\u7565\u8207\u6a5f\u5236\u5206\u5bb6<\/h2>\n\n\n\n<p>\u65e2\u7136 Kernel \u7b28\u53c8\u96e3\u8abf\uff0c\u90a3\u6211\u5011\u5c31\u8b93 User Space \u4f86\u6c7a\u5b9a\u7b56\u7565\uff0cKernel \u5c08\u5fc3\u57f7\u884c\u6307\u4ee4\u3002\u9019\u5c31\u662f <strong>Userspace LMKD<\/strong> \u7684\u8a95\u751f\u3002<\/p>\n\n\n\n<p>\u4f46\u7b49\u7b49\uff0c\u8981\u8b93 User Space \u638c\u63a7\u72c0\u6cc1\uff0c\u7e3d\u8981\u6709\u8fa6\u6cd5\u5f97\u77e5\u300c\u73fe\u5728\u58d3\u529b\u591a\u5927\u300d\u5427\uff1f<\/p>\n\n\n\n<p>LMKD \u5c0d\u6b64\u53c8\u5206\u6210\u5169\u500b\u968e\u6bb5\uff0c\u90fd\u7b26\u5408 User space \u80fd\u8b80\u53d6\u5230\u7684\u9019\u500b\u689d\u4ef6<\/p>\n\n\n\n<ol>\n<li><strong>Vmpressure<\/strong> \u662f Linux kernel \u63d0\u4f9b\u7684\u4e00\u7a2e <strong>\u5167\u90e8\u901a\u77e5\u6a5f\u5236<\/strong>\uff0c\u8b93\u7528\u6236\u7a7a\u9593\uff08userspace\uff09\u80fd\u5373\u6642\u77e5\u9053\u76ee\u524d\u8a18\u61b6\u9ad4\u662f\u5426\u300c\u5403\u7dca\u300d\uff0c\u4f46\u5b83\u4e0d\u662f\u900f\u904e\u89c0\u5bdf\u300cfree memory\u300d\u9019\u7a2e\u975c\u614b\u6307\u6a19\uff0c\u800c\u662f\u900f\u904e\u89c0\u5bdf\u300ckernel \u5728 reclaim \u9801\u9762\u6642\u767c\u51fa\u7684 event\u300d\u4f86\u63a8\u4f30\u3002<\/li>\n<\/ol>\n\n\n<div class=\"wp-block-image\">\n<figure class=\"aligncenter size-large is-resized\"><a href=\"https:\/\/boochlin.com\/wp-content\/uploads\/2025\/05\/image-1.png\"><img decoding=\"async\" width=\"1024\" height=\"550\" src=\"https:\/\/boochlin.com\/wp-content\/uploads\/2025\/05\/image-1-1024x550.png\" alt=\"\" class=\"wp-image-497\" style=\"width:499px;height:auto\" srcset=\"https:\/\/boochlin.com\/wp-content\/uploads\/2025\/05\/image-1-1024x550.png 1024w, https:\/\/boochlin.com\/wp-content\/uploads\/2025\/05\/image-1-300x161.png 300w, https:\/\/boochlin.com\/wp-content\/uploads\/2025\/05\/image-1-768x413.png 768w, https:\/\/boochlin.com\/wp-content\/uploads\/2025\/05\/image-1.png 1314w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/a><\/figure><\/div>\n\n\n<ul>\n<li>PSI\uff08Pressure Stall Information\uff09\u900f\u904e\u8ffd\u8e64\u4efb\u52d9\u56e0\u8cc7\u6e90\u4e0d\u8db3\uff08<code>psi_memstall_enter<\/code> \u548c <code>psi_memstall_leave<\/code> \u51fd\u6578\u8a18\u9304\u7684\u8a18\u61b6\u9ad4\u505c\u6eef\u6642\u9593\u6700\u521d\u4ee5\u6bcf\u500b CPU \u7684\u8a08\u6578\u5668\u5f62\u5f0f\u7dad\u8b77 \uff09\u800c\u88ab\u5ef6\u9072\u7684\u6642\u9593\uff0c\u63d0\u4f9b\u4e86\u66f4\u6e96\u78ba\u7684\u58d3\u529b\u6307\u6a19\u3002\u9019\u4e9b\u5ef6\u9072\u76f4\u63a5\u5f71\u97ff\u4f7f\u7528\u8005\u9ad4\u9a57\uff0c\u56e0\u6b64 PSI \u80fd\u5920\u66f4\u771f\u5be6\u5730\u53cd\u6620\u7cfb\u7d71\u7684\u58d3\u529b\u72c0\u6cc1\u3002<\/li>\n\n\n\n<li>\u63d0\u4f9b\u4e86 <code>some<\/code> \u548c <code>full<\/code> \u5169\u7a2e\u58d3\u529b\u6307\u6a19\uff1a\n<ul>\n<li><strong>some<\/strong>\uff1a\u8868\u793a\u81f3\u5c11\u6709\u4e00\u500b\u4efb\u52d9\u56e0\u8cc7\u6e90\u4e0d\u8db3\u800c\u88ab\u5ef6\u9072\u7684\u6642\u9593\u6bd4\u4f8b\u3002<\/li>\n\n\n\n<li><strong>full<\/strong>\uff1a\u8868\u793a\u6240\u6709\u975e\u9592\u7f6e\u4efb\u52d9\u540c\u6642\u56e0\u8cc7\u6e90\u4e0d\u8db3\u800c\u88ab\u5ef6\u9072\u7684\u6642\u9593\u6bd4\u4f8b<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<blockquote class=\"wp-block-quote\">\n<p>\u5404\u4f4d\u6709\u6c92\u6709\u611f\u89ba\u660e\u986f Vmpressure \u4e0d\u5920\u7cbe\u6e96\uff0c\u6709\u9ede\u4e8b\u5f8c\u8af8\u845b\u7684\u65b9\u5f0f\u4f86\u53cd\u63a8\u8a18\u61b6\u9ad4\u58d3\u529b\uff0c\u80af\u5b9a\u6703\u6709\u5ef6\u9072\uff0c\u537b\u662f\u65e9\u671f android \u5148\u5c0e\u5165\u7684\u5c0d\u8c61\uff0c\u6c92\u932f\uff0c\u6211\u4e5f\u89ba\u7684\u5f88\u5947\u602a\uff0c\u4f46\u539f\u56e0\u597d\u50cf\u883b\u7c21\u55ae\u7684<\/p>\n<\/blockquote>\n\n\n\n<p>\u5c31\u662f<\/p>\n\n\n\n<blockquote class=\"wp-block-quote\">\n<p><code>vmpressure<\/code> \u662f\u5f9e Linux kernel 3.14 \u5c31\u958b\u59cb\u6709\u7684<\/p>\n\n\n\n<p><code>PSI<\/code>\uff08Pressure Stall Information\uff09\u5247\u662f <strong>kernel 4.20<\/strong> \u624d\u88ab\u5f15\u5165<\/p>\n<\/blockquote>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>\u5c0d\u7576\u6642\u7684\u4f7f\u7528\u5834\u666f\u4e5f\u5df2\u8db3\u5920<\/strong><\/h3>\n\n\n\n<ul>\n<li>\u65e9\u671f Android \u8ffd\u6c42\u7684\u662f\u591a\u5de5\u9ad4\u9a57\uff08\u5207 app\u3001\u5feb\u56de\u61c9\uff09\uff0c\u56e0\u6b64\u53ea\u8981\u77e5\u9053\u300c\u8a18\u61b6\u9ad4\u58d3\u529b\u4f86\u4e86\u300d\u5c31\u5920\u7528\u3002<\/li>\n\n\n\n<li><code>vmpressure<\/code> \u80fd\u5728 page reclaim \u7121\u6548\u6642\u767c\u51fa\u300c\u5feb\u7206\u4e86\u300d\u7684\u901a\u77e5\uff0c\u5920\u61c9\u4ed8\u65e9\u671f\u300c\u6bba\u5f8c\u53f0 app \u4fdd\u524d\u53f0 smooth\u300d\u7684\u9700\u6c42\u3002<\/li>\n<\/ul>\n\n\n\n<p>\u5230\u4e86\u9019\u908a\uff0c\u662f\u4e0d\u662f\u89ba\u5f97\u8b1b\u7684\u592a\u591a\uff0c\u6574\u500b\u6545\u4e8b\u7dda\u90fd\u63d0\u5b8c\u4e86<\/p>\n\n\n\n<p>\u8a18\u4f4f \u6211\u5011\u662f\u5e0c\u671b\u6253\u9020\u51fa\u9069\u5408\u6211\u5011\u7684 AI \u4eba\u81c9\u8fa8\u8b58\u88dd\u7f6e\uff0c\u800c\u4e0d\u662f Android \u88dd\u7f6e\u6240\u8ffd\u6c42\u7684 \u5feb\u901f\u5207\u63db\uff0c\u7d72\u6ed1\u64cd\u4f5c\u552f\u4e00\u91cd\u8981\u7684\u300c\u524d\u666f\u61c9\u7528\u7a0b\u5f0f\u300d\u5c31\u662f\u60a8\u958b\u767c\u7684\u4eba\u81c9\u8fa8\u8b58\u7a0b\u5f0f\u3002\u5176\u4ed6\u6240\u6709\u7cfb\u7d71\u670d\u52d9\u3001\u80cc\u666f\u7a0b\u5e8f\uff0c\u53ea\u8981\u4e0d\u662f\u7dad\u6301\u4eba\u81c9\u8fa8\u8b58\u6838\u5fc3\u529f\u80fd\u6240\u5fc5\u9700\u7684\uff0c\u90fd\u61c9\u8a72\u88ab\u8996\u70ba\u53ef\u72a7\u7272\u7684\u8cc7\u6e90\u3002\u6211\u5011\u7684 LMKD \u8abf\u6821\u76ee\u6a19\u662f\uff1a<\/p>\n\n\n\n<ul>\n<li>\u78ba\u4fdd\u4eba\u81c9\u8fa8\u8b58\u61c9\u7528\u7a0b\u5f0f\uff08\u4f5c\u70ba\u524d\u666f\u7a0b\u5e8f\uff09\u5728\u4efb\u4f55\u60c5\u6cc1\u4e0b\u90fd\u4e0d\u6703\u88ab LMKD \u7d42\u6b62\u3002<\/li>\n\n\n\n<li>\u5728\u8a18\u61b6\u9ad4\u58d3\u529b\u5347\u9ad8\u6642\uff0cLMKD \u61c9\u512a\u5148\u4e14\u7a4d\u6975\u5730\u7d42\u6b62\u8207\u4eba\u81c9\u8fa8\u8b58\u7121\u95dc\u7684\u7cfb\u7d71\u670d\u52d9\u6216\u80cc\u666f\u7a0b\u5e8f\u3002<\/li>\n\n\n\n<li>\u5229\u7528 PSI \u63d0\u4f9b\u7684\u7cbe\u78ba\u8a18\u61b6\u9ad4\u58d3\u529b\u8cc7\u8a0a\uff0c\u907f\u514d\u4e0d\u5fc5\u8981\u7684\u7d42\u6b62\uff0c\u540c\u6642\u78ba\u4fdd\u5728\u5fc5\u8981\u6642\u80fd\u53ca\u6642\u4ecb\u5165\u3002<\/li>\n<\/ul>\n\n\n\n<p><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code># Set device as low-RAM\nro.config.low_ram=true\n\n# Use PSI for memory pressure detection (requires kernel support)\nro.lmk.use_psi=true\nro.lmk.use_minfree_levels=false\n\n# Adjust PSI thresholds (start with defaults for low-RAM, may need tuning)\nro.lmk.psi_partial_stall_ms=200\nro.lmk.psi_complete_stall_ms=700\n\u9019\u4e9b\u6578\u5b57\u53ef\u80fd\u9700\u8981\u964d\u4f4e\uff0c\u4f46\u6211\u78ba\u5be6\u6700\u5f8c\u5b9a\u8abf\u5728\u9019\u5169\u6578\u5b57\uff0c\u8d8a\u4f4e\u7684\u8a71\uff0c\u53ef\u4ee5\u8b93 LMKD \u63d0\u65e9\u958b\u59cb\u8655\u7406\u8a18\u61b6\u9ad4\u4e0d\u8db3\u7684\u554f\u984c\uff0c\u4f46\u662f\u592a\u4f4e\u53ef\u80fd\u9020\u6210\u7cfb\u7d71\u4e0d\u6bb5\u958b\u95dc process \uff0c\u53cd\u800c\u66f4\u7cdf\n\n# Adjust oom_adj thresholds for killing (protect foreground, aggressively kill others)\n# Target cached apps (oom_adj 900-1000) at low pressure \u9810\u8a2d\u503c 1001\uff08\u7981\u7528\uff09\u8868\u793a\u5728\u4f4e\u58d3\u529b\u4e0b\u4e0d\u7d42\u6b62\u4efb\u4f55\u7a0b\u5e8f\nro.lmk.low=900\n# Target services (oom_adj 500-800) at medium pressure\nro.lmk.medium=500\n# Critical pressure allows killing any process (oom_adj 0), last resort\nro.lmk.critical=0\n\u524d\u666f\u61c9\u7528\u7a0b\u5f0f\u7684 oom_adj \u662f 0\uff0c\u9019\u662f\u6700\u5f8c\u4e00\u9053\u9632\u7dda\u3002\u4fdd\u6301\u70ba 0 \u662f\u5fc5\u8981\u7684\uff0c\u4f46\u6211\u5011\u7684\u76ee\u6a19\u662f\u900f\u904e\u7a4d\u6975\u7d42\u6b62\u9ad8 oom_adj \u7a0b\u5e8f\u4f86\u907f\u514d\u9054\u5230\u9019\u500b\u72c0\u614b\u3002\n\n# Kill the heaviest eligible task to free memory quickly\nro.lmk.kill_heaviest_task=true\n<\/code><\/pre>\n\n\n\n<p>\u9664\u4e86\u9019\u500b\u90e8\u5206\uff0c\u9084\u6709\u4e00\u500b\u5730\u65b9 Framework \u5c64\u53ef\u4ee5\u4e0b\u624b\u770b\u770b <strong>ActivityManagerService<\/strong>\uff0e<strong>ActivityManagerConstants<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>frameworks_base_services\/java\/com\/android\/server\/am\n\/ProcessList.java<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>CUR_TRIM_EMPTY_PROCESSES\n = computeTrimEmptyApps(rawMaxEmptyProcesses);\nCUR_TRIM_CACHED_PROCESSES =\n               computeTrimCachedApps(rawMaxEmptyProcesses, MAX_CACHED_PROCESSES);\nMAX_CACHED_PROCESSES : <strong>32-&gt;3<\/strong>\n\n\/**\n    * Return the maximum pss size in kb that we consider a process acceptable to\n    * restore from its cached state for running in the background when RAM is low.\n    *\/\n   long getCachedRestoreThresholdKb() {\n       \/\/ heaton\n       Slog.w(TAG, \"getCachedRestoreThresholdKb \"+mCachedRestoreLevel);\n       return mCachedRestoreLevel<strong>\/10;<\/strong>\n   }\n\u4fdd\u75591\/10 \u7684\u4e00\u73edcache memory.\n<\/code><\/pre>\n\n\n\n<p><strong>MAX_CACHED_PROCESSES<\/strong> \u9650\u5236\u7cfb\u7d71\u5728\u8a18\u61b6\u9ad4\u5145\u8db3\u6642\u6700\u591a\u4fdd\u7559\u591a\u5c11\u5feb\u53d6\u7a0b\u5e8f\u7684\u6578\u91cf \uff0c\u4e0d\u9700\u8981\u4fdd\u7559\u5927\u91cf\u5feb\u53d6\u7a0b\u5e8f\u4f86\u5be6\u73fe\u5feb\u901f\u591a\u5de5\u5207\u63db<\/p>\n\n\n\n<p><strong>getCachedRestoreThresholdKb<\/strong> \u964d\u4f4e\u70ba\u539f\u672c\u76841\/10\u6703\u4f7f\u5f97\u8a18\u61b6\u9ad4\u4f7f\u7528\u91cf\u76f8\u5c0d\u8f03\u9ad8\u7684\u5feb\u53d6\u7a0b\u5e8f\u66f4\u5bb9\u6613\u88ab\u7cfb\u7d71\u6e05\u7406<\/p>\n\n\n\n<p>\u9019\u5169\u500b\u53c3\u6578\u5be6\u969b\u4e0a\u4f7f\u7528\u8d77\u4f86\u975e\u5e38\u6709\u6548\uff0c\u5f88\u5feb\u5c31\u53ef\u4ee5\u770b\u5230\u6578\u64da\u7684\u8b8a\u5316\uff0c\u4f46\u662f\u76f4\u63a5\u8abf\u6574\u9019\u4e9b\u6578\u64da\u6709\u53ef\u80fd\u6703\u8ddf low mem\u7684\u90e8\u5206\u53c3\u6578\u8d77\u5230\u885d\u7a81\uff0c\u4ee5\u53ca\u660e\u986f\u6c92\u6709 cache process \u53ef\u80fd\u5e36\u4f86\u7684\u554f\u984c\uff0c\u4e5f\u5c31\u662f\u7576\u771f\u7684\u6709\u7528\u5230\u7684 process \u53ef\u80fd\u56e0\u70ba\u6fc0\u70c8\u7684 kill \u53ca \u91cd\u65b0\u555f\u52d5\u9020\u6210 CPU loading \u63d0\u9ad8\uff0c\u4f8b\u5982\uff0c\u67d0\u4e9b\u770b\u4f3c\u4e0d\u91cd\u8981\u7684\u80cc\u666f\u670d\u52d9\u53ef\u80fd\u5be6\u969b\u4e0a\u70ba\u76f8\u6a5f\u4e32\u6d41\u6216 AI \u63a8\u7406\u63d0\u4f9b\u5e95\u5c64\u652f\u63f4\u3002\u6240\u4ee5\u70ba\u4f55\u524d\u9762\u7684\u7ae0\u7bc0\u6703\u5148\u8981\u6c42 \u5b78\u6703 \u201c<strong>\u8a55\u4f30<\/strong>\u201d<\/p>\n\n\n\n<figure class=\"wp-block-pullquote\"><blockquote><p>\u9019\u4e9b\u8abf\u6821\u90fd\u9700\u8981\u5728\u60a8\u7684\u88dd\u7f6e\u4e0a\u9032\u884c\u4ed4\u7d30\u7684\u6e2c\u8a66\u548c\u76e3\u63a7\uff0c\u4ee5\u78ba\u4fdd\u5728\u7a4d\u6975\u91cb\u653e\u8a18\u61b6\u9ad4\u7684\u540c\u6642\uff0c\u4e0d\u6703\u5f71\u97ff\u5230\u6838\u5fc3\u7684\u4eba\u81c9\u8fa8\u8b58\u61c9\u7528\u7a0b\u5f0f\u7684\u7a69\u5b9a\u904b\u884c\u3002<\/p><\/blockquote><\/figure>\n\n\n\n<p>\u591a\u500b\u5c0f\u6545\u4e8b\uff0c\u91dd\u5c0d LMKD\uff0c\u7d50\u8ad6\u4f86\u8aaa\u6211\u5011\u6703\u5e0c\u671b\u662f Userspace LMKD + PSI \uff0e\u7576\u521d\u4f7f\u7528 Android 10 \u7d93\u904e\u4e00\u5806\u8abf\u6574\u5f8c\uff0c\u9084\u662f\u767c\u73fe\u904e\u4e00\u4e9b\u975e\u9810\u671f\u7684\u60c5\u6cc1\uff0c\u5c31\u662f\u4e0d\u77e5\u9053\u70ba\u4f55\u522a\u6389\u9810\u60f3\u5916\u7684 background \uff0c \u6211\u4e00\u76f4\u4ee5\u70ba\u662f LMKD \u641e\u932f\u53c3\u6578\uff0c\u5f8c\u4f86\u770b\u8005\u770b\u8005 Log \u624d\u767c\u73fe lowmemorykiller \u600e\u9ebc\u4e5f\u5728\u904b\u884c\uff0c\u9019\u624d\u7a81\u7834\u6211\u56fa\u5b9a\u7684\u601d\u8003\u6a21\u5f0f\uff0c\u539f\u4f86\u662f\u6709\u53ef\u80fd\u4e00\u5957\u7cfb\u7d71\u4e2d\u6709\u5169\u5957\u8a18\u61b6\u9ad4\u7ba1\u7406\u6a5f\u5236\u5728\u904b\u884c\uff0c\u6975\u6709\u53ef\u80fd\u7576\u6642\u5728porting \u6642\u6c92\u6709\u6ce8\u610f\u5230<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>adb shell ps -A | grep lmkd \n\u8f38\u51fa\u4e2d\u5305\u542b lmkd \u76f8\u95dc\u7684\u884c\uff0c\u8868\u793a LMKD \u6b63\u5728\u904b\u884c\nadb shell getprop ro.lmk.use_psi \ntrue\uff0c\u8868\u793a LMKD \u88ab\u914d\u7f6e\u70ba\u4f7f\u7528 PSI \u9032\u884c\u8a18\u61b6\u9ad4\u58d3\u529b\u5075\u6e2c \u3002\nfalse \u6216\u6c92\u6709\u8f38\u51fa\uff0c\u5247\u53ef\u80fd\u8868\u793a\u4f7f\u7528 vmpressure \u6216\u50b3\u7d71\u6a21\u5f0f\u3002\n\nadb shell logcat | grep lowmemorykiller\nadb shell logcat | grep lmkd\nUsing psi monitors for memory pressure detection \uff1a\u9019\u660e\u78ba\u8868\u793a LMKD \u6b63\u5728\u4f7f\u7528 PSI\u3002 \nUsing vmpressure for memory pressure detection \uff1a\u8868\u793a\u4f7f\u7528\u8f03\u820a\u7684 vmpressure \u6a5f\u5236\u3002&nbsp; \nadb shell ls \/proc\/pressure\/\n\u5982\u679c\u8f38\u51fa\u5305\u542b cpu, io, memory \u7b49\u6a94\u6848\uff0c\u8868\u793a\u6838\u5fc3\u652f\u63f4 PSI.\n\n\u5e95\u4e0b\u9019\u6bb5\u8a2d\u7f6e\u53ef\u4ee5\u8a66\u8a66\u770b\uff0c\u78ba\u4fdd\u6211\u5011\u8981\u4f7f\u7528\u7684 lmkd \u6a21\u5f0f<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>CONFIG_ANDROID_LOW_MEMORY_KILLER=n \u7981\u7528\u50b3\u7d71\u7684\u6838\u5fc3\u5167\u5efa\u4f4e\u8a18\u61b6\u9ad4\u7d42\u6b62\u5668 (in-kernel LMK) \u9a45\u52d5\u7a0b\u5f0f\nCONFIG_MEMCG=y \u555f\u7528\u4e86 Linux \u6838\u5fc3\u7684\u8a18\u61b6\u9ad4\u63a7\u5236\u7fa4\u7d44 (Memory Cgroups) \u529f\u80fd\nCONFIG_MEMCG_SWAP=y \u555f\u7528\u4e86\u8a18\u61b6\u9ad4 cgroup \u7684\u4ea4\u63db (Swap) \u5e33\u6236\u529f\u80fd\n\n<\/code><\/pre>\n\n\n\n<p>\u6700\u5f8c\u5c55\u793a\u4e00\u4e0b\u7d50\u679c<\/p>\n\n\n\n<p>before<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>Total RAM: 1,909,104K (status normal)\n Free RAM:   456,339K (  140,995K cached pss +   251,112K cached kernel +    64,232K free)\n Used RAM: 1,503,496K (1,301,496K used pss +   202,000K kernel)\n Lost RAM:   125,250K\n     ZRAM:    44,240K physical used for   225,168K in swap (  524,284K total swap)\n      KSM:    26,640K saved from shared       828K              20,964K unshared;     6,096K\n\n\nfinal\n\nTotal RAM: 1,909,104K (status normal)\n Free RAM: 1,135,724K (   56,072K cached pss +   609,924K cached kernel +   469,728K free)\n Used RAM:   804,931K (  641,123K used pss +   163,808K kernel)\n Lost RAM:   137,107K\n     ZRAM:    39,672K physical used for   212,468K in swap (  262,140K total swap)\n      KSM:     2,872K saved from shared        72K              14,204K unshared;       572K volatile\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>\u300a\u6bba\u7684\u4e0d\u662f Process\uff0c\u662f\u6211\u7684\u5e79\u8a71\u6642\u9593\u300b<\/p>\n<p>\u3010\u4f60\u4ee5\u70ba\u95dc\u6389\u5e7e\u500b\u6c92\u7528\u7684 system service \u5c31\u89e3\u6c7a\u4e86\uff1f\u3011<\/p>\n<p>\u5225\u5929\u771f\u4e86\uff0cAndroid \u672c\u4f86\u5c31\u6709\u4e00\u5957\u300c\u5feb\u7206\u4e86\u6211\u4f86\u6bba\u4eba\u300d\u7684\u5167\u5efa\u6a5f\u5236\uff0c\u540d\u70ba\uff1a<\/p>\n<p>Low-Memory Killer Daemon<\/p>\n","protected":false},"author":1,"featured_media":559,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[80],"tags":[],"_links":{"self":[{"href":"https:\/\/boochlin.com\/index.php?rest_route=\/wp\/v2\/posts\/431"}],"collection":[{"href":"https:\/\/boochlin.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/boochlin.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/boochlin.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/boochlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=431"}],"version-history":[{"count":23,"href":"https:\/\/boochlin.com\/index.php?rest_route=\/wp\/v2\/posts\/431\/revisions"}],"predecessor-version":[{"id":605,"href":"https:\/\/boochlin.com\/index.php?rest_route=\/wp\/v2\/posts\/431\/revisions\/605"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/boochlin.com\/index.php?rest_route=\/wp\/v2\/media\/559"}],"wp:attachment":[{"href":"https:\/\/boochlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=431"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/boochlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=431"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/boochlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=431"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}