{"id":7326,"date":"2022-08-30T11:07:48","date_gmt":"2022-08-30T03:07:48","guid":{"rendered":"https:\/\/egonlin.com\/?p=7326"},"modified":"2022-08-30T17:09:46","modified_gmt":"2022-08-30T09:09:46","slug":"03-%e5%ae%b9%e5%99%a8%e7%9a%84%e9%95%9c%e5%83%8f%e4%b8%8eunionfs","status":"publish","type":"post","link":"https:\/\/egonlin.com\/?p=7326","title":{"rendered":"03 \u5bb9\u5668\u7684\u955c\u50cf\u4e0eUnionFS"},"content":{"rendered":"<p>\u5bb9\u5668\u7684\u955c\u50cf\u6784\u6210\u76f4\u63a5\u5173\u7cfb\u5230\u4f60\u5bf9\u542f\u52a8\u4e00\u4e2a\u5bb9\u5668\u7684\u7406\u89e3 \uff0c\u975e\u5e38\u91cd\u8981<\/p>\n<h1>\u4e00 \u5f15\u5165\u95ee\u9898<\/h1>\n<p>\u6bcf\u542f\u52a8\u4e00\u4e2a\u5bb9\u5668\uff0c\u5728\u5bb9\u5668\u5185\u90fd\u6709\u4e00\u4e2a\u64cd\u4f5c\u7cfb\u7edf\uff0c\u8fd9\u91cc\u6709\u4e24\u4e2a\u95ee\u9898\u6211\u4eec\u9700\u8981\u641e\u6e05\u695a<\/p>\n<p>\uff081\uff09\u5bb9\u5668\u7684\u64cd\u4f5c\u7cfb\u7edf\u6765\u6e90\u4e8e\u4ec0\u4e48\uff1f<\/p>\n<p>\uff082\uff09\u6211\u4eec\u662f\u5982\u4f55\u628a\u64cd\u4f5c\u7cfb\u7edf\u5b89\u88c5\u5230\u5bb9\u5668\u91cc\u7684\uff1f<\/p>\n<h1>\u4e8c \u5bb9\u5668\u7684\u64cd\u4f5c\u7cfb\u7edf\u6765\u6e90<\/h1>\n<h2>2.1 \u64cd\u4f5c\u7cfb\u7edf\u7684\u6765\u6e90<\/h2>\n<p>\u4f60\u4e00\u5b9a\u4e3a\u7269\u7406\u673a\/\u865a\u62df\u673a\u5b89\u88c5\u8fc7\u64cd\u4f5c\u7cfb\u7edf\uff0c\u5177\u4f53\u4f60\u662f\u5148\u4e0b\u8f7d\u4e86\u4e00\u4e2a\u7cfb\u7edf\u955c\u50cf\u6587\u4ef6\uff0c\u7136\u540e\u628a\u8be5\u955c\u50cf\u5199\u5230\u4e86u\u76d8\u6216\u5149\u76d8\u91cc\u79f0\u4e4b\u4e3a\u542f\u52a8\u76d8\uff0c\u7136\u540e\u7528\u6765\u4e3a\u673a\u5668\u5b89\u88c5\u64cd\u4f5c\u7cfb\u7edf\u3002\u4e5f\u5c31\u8bf4\u4e00\u53f0\u673a\u5668\u7684\u64cd\u4f5c\u7cfb\u7edf\u6765\u81ea\u4e8e\u4e00\u4e2a\u955c\u50cf\u6587\u4ef6\uff0c\u6211\u4eec\u79f0\u4e4b\u4e3a\u7cfb\u7edf\u955c\u50cf\u3002<\/p>\n<p>\u4e00\u4e2a\u5bb9\u5668\u5c31\u76f8\u5f53\u4e8e\u4e00\u53f0\u201c\u865a\u62df\u673a\u201d\uff0c\u65e2\u7136\u865a\u62df\u673a\u7684\u64cd\u4f5c\u7cfb\u7edf\u6765\u6e90\u4e8e\u955c\u50cf\uff0c\u90a3\u4e48\u5bb9\u5668\u5185\u7684\u64cd\u4f5c\u7cfb\u7edf\u5fc5\u7136\u4e5f\u6765\u6e90\u4e8e\u955c\u50cf\u4e86\uff1f\u5b8c\u5168\u6b63\u786e<\/p>\n<p>\u4f46\u56e0\u4e3a\u5bb9\u5668\u8981\u505a\u5230\u5168\u65b9\u4f4d\u7684\u8f7b\u91cf\u7ea7\uff0c\u6240\u4ee5\u5bb9\u5668\u7684\u64cd\u4f5c\u7cfb\u7edf\u955c\u50cf\u5fc5\u7136\u4e5f\u8981\u662f\u5728\u4e00\u4e2a\u5b8c\u6574\u64cd\u4f5c\u7cfb\u7edf\u955c\u50cf\u7684\u57fa\u7840\u4e0a\u505a\u7cbe\u7b80\uff0c\u5177\u4f53\u5982\u4f55\u5b9e\u73b0\u7684\u5462\uff1f\u6211\u4eec\u6765\u4e00\u4e00\u89e3\u6790<\/p>\n<h2>2.2 \u5b8c\u6574\u64cd\u4f5c\u7cfb\u7edf\u7684\u955c\u50cf<\/h2>\n<p>\u955c\u50cf\u7684\u672c\u8d28\u5c31\u662f\u4e00\u4e2aiso\u683c\u5f0f\u7684\u538b\u7f29\u5305\uff0c\u64cd\u4f5c\u7cfb\u7edf\u955c\u50cf\u91cc\u9762\u5b58\u653e\u4e86\u8be5\u7cfb\u7edf\u6240\u6709\u7684\u5185\u5bb9\uff0c\u5177\u4f53\u6765\u8bf4\u5206\u4e3a\u4e24\u5927\u90e8\u5206<\/p>\n<p>\u4e00\u4e2a\u5178\u578b\u7684 Linux \u6587\u4ef6\u7cfb\u7edf\u7531 bootfs \u548c rootfs \u4e24\u90e8\u5206\u7ec4\u6210<\/p>\n<ul>\n<li>1\u3001bootfs(boot file system) \u4e3b\u8981\u5305\u542b bootloader \u548c kernel\uff0cbootloader \u4e3b\u8981\u7528\u4e8e\u5f15\u5bfc\u52a0\u8f7d kernel\uff0c\u5f53 kernel \u88ab\u52a0\u8f7d\u5230\u5185\u5b58\u4e2d\u540e bootfs \u4f1a\u88ab umount \u6389\uff0c\u4ece\u800c\u91ca\u653e\u5185\u5b58\uff0c\u540c\u6837\u7684\u5185\u6838\u7248\u672c\u4e0d\u540cLinux\u53d1\u884c\u7248\uff0c\u5176bootfs\u90fd\u662f\u4e00\u81f4\u7684\u3002 <\/li>\n<li>2\u3001rootfs (root file system) \u5305\u542b\u7684\u5c31\u662f\u5178\u578b Linux \u7cfb\u7edf\u4e2d\u7684\/dev\uff0c\/proc\uff0c\/bin\uff0c\/etc \u7b49\u6807\u51c6\u76ee\u5f55\u548c\u6587\u4ef6\u3002Linux\u7cfb\u7edf\u5728\u542f\u52a8\u65f6\uff0crootfs\u9996\u5148\u4f1a\u88ab\u6302\u8f7d\u4e3a\u53ea\u8bfb\u6a21\u5f0f\uff0c\u7136\u540e\u5728\u542f\u52a8\u5b8c\u6210\u540e\u88ab\u4fee\u6539\u4e3a\u8bfb\u5199\u6a21\u5f0f\uff0c\u968f\u540e\u5b83\u4eec\u5c31\u53ef\u4ee5\u88ab\u4fee\u6539\u4e86\u3002\u4e0d\u540c\u7684 linux \u53d1\u884c\u7248\uff08\u5982 ubuntu \u548c CentOS ) \u5728 rootfs \u8fd9\u4e00\u5c42\u4f1a\u6709\u6240\u533a\u522b\uff0c\u4f53\u73b0\u53d1\u884c\u7248\u672c\u7684\u5dee\u5f02\u6027\u3002<\/li>\n<\/ul>\n<h2>2.3 docker image\u662f\u4ec0\u4e48\uff1f\u5982\u4f55\u6784\u6210\u7684<\/h2>\n<p>\u4e0a\u4e00\u5c0f\u8282\u63d0\u5230\uff0c\u4e00\u4e2a\u5b8c\u6574\u7684\u6587\u4ef6\u7cfb\u7edf\u662f\u7531bootfs+rootfs\u7ec4\u6210\u7684<\/p>\n<p>\u800c\u5bb9\u5668image\u955c\u50cf\u5176\u5b9e\u5c31\u662f\u628arootfs\u6253\u5305\u5230\u4e00\u8d77\uff08\u955c\u50cf\u7684\u672c\u8d28\u5c31\u662f\u4e00\u79cd\u538b\u7f29\u5305\uff09\uff0c\u8fd9\u4e2arootfs\u7cfb\u7edf\u91cc\u5305\u542b\u4e86\u5404\u79cd\u4f9d\u8d56\u6587\u4ef6\uff0c\u4ee5\u53ca\u4f60\u7684\u5e94\u7528\u7a0b\u5e8f\u6587\u4ef6\u90fd\u5728\u4e00\u8d77\u3002<\/p>\n<p>\u4e5f\u5c31\u8bf4\u4e16\u754c\u4e0a\u7b2c\u4e00\u4e2a\u955c\u50cf\u662f\u600e\u4e48\u4ea7\u751f\u7684\u5462\uff1f<\/p>\n<p>\u5c31\u662f\u67d0\u4eba\u5728\u4e00\u53f0\u7269\u7406\u673a\u4e0a\u5b89\u88c5\u4e86\u4e00\u4e2alinux\u64cd\u4f5c\u7cfb\u7edf\uff0c\u5305\u62ecbootfs\uff0c\u4e5f\u5305\u62ecrootfs\uff0c\u7136\u540e\u4ed6\u5728rootfs\u91cc\u5b89\u88c5\u4e86\u5404\u79cd\u4f9d\u8d56\u5305\uff0c\u505a\u597d\u4e86\u8f6f\u4ef6\u542f\u52a8\u7684\u4e00\u5207\u914d\u7f6e\uff0c\u7136\u540e\u4ed6\u628a\u8fd9\u4e2arootfs\uff08\u8bd1\uff1a\u6839\u6587\u4ef6\u7cfb\u7edf\uff09\u6253\u5305\u538b\u7f29\u6210\u4e86\u4e00\u4e2a\u6587\u4ef6\uff0c\u8fd9\u4e2a\u6587\u4ef6\u5c31\u79f0\u4e4b\u4e3adocker\u7684image\uff0c\u4e5f\u5c31\u662f\u955c\u50cf\u3002<\/p>\n<p>\u6211\u4eec\u542f\u52a8\u4e00\u4e2a\u5bb9\u5668\uff0c\u5fc5\u987b\u6307\u5b9a\u4e00\u4e2a\u955c\u50cf\uff0c\u955c\u50cf\u91cc\u5305\u542b\u7684\u662frootfs\uff0c\u76ee\u7684\u5c31\u662f\u628a\u955c\u50cf\u6587\u4ef6\u5171\u4eab\u7ed9\u4e86\u5bb9\u5668\u7684\u540d\u79f0\u7a7a\u95f4\u91cc\uff0c\u5728\u5bb9\u5668\u5185\uff0c\u53ef\u4ee5\u770b\u5230\u5b8c\u5168\u72ec\u7acb\u7684\u6587\u4ef6\u7cfb\u7edf\uff0c\u67e5\u770b\u5bb9\u5668\u4e2d\u7684\u6839\u6587\u4ef6\u7cfb\u7edf (rootfs)\u3002\u7136\u540e\uff0c\u4f60\u4f1a\u53d1\u73b0\uff0c\u5b83\u548c\u5bbf\u4e3b\u673a\u4e0a\u7684\u6839\u6587\u4ef6\u7cfb\u7edf\u4e5f\u662f\u4e0d\u4e00\u6837\u7684\u3002\u6240\u4ee5\u6b64\u65f6\u4f60\u5e94\u8be5\u77e5\u9053\u4e86\uff0c\u5728\u5bb9\u5668\u91cc\u770b\u5230\u7684\u6839\u6587\u4ef6\u7cfb\u7edf\uff0c\u5c31\u662f\u955c\u50cf\u91cc\u7684\u4e1c\u897f\u3002\u4e0b\u56fedocker image \u4e2d\u6700\u57fa\u7840\u7684\u4e24\u5c42\u7ed3\u6784\uff0c\u4e0d\u540c\u7684 linux \u53d1\u884c\u7248\uff08\u5982 ubuntu \u548c CentOS ) \u5728 rootfs \u8fd9\u4e00\u5c42\u4f1a\u6709\u6240\u533a\u522b\uff0c\u4f53\u73b0\u53d1\u884c\u7248\u672c\u7684\u5dee\u5f02\u6027\u3002<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/2.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/2.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u9700\u8981\u518d\u6b21\u5f3a\u8c03\u7684\u4e00\u70b9\u5c31\u662f\uff0c\u5bb9\u5668\u672c\u8d28\u662f\u6ca1\u6709\u5185\u6838\u7684\u3001\u5b83\u53ea\u6709rootfs\uff0c\u81f3\u4e8e\u4e0b\u5c42\u7684bootfs\u5185\u6838\u90e8\u5206\u662f\u5171\u4eab\u81ea\u7269\u7406\u673a\u7684\uff0c\u5e76\u4e14\u6240\u6709\u5bb9\u5668\u5171\u4eab\u7684\u90fd\u662f\u7269\u7406\u4e3b\u673a\u4e0a\u7684\u8fd0\u884c\u7cfb\u7edf\u7684\u5185\u6838\u5373bootfs\u76f8\u5173\u5185\u5bb9\u3002<\/p>\n<p>ps\uff1a\u7269\u7406\u673a\u8fd0\u884c\u7684\u6587\u4ef6\u7cfb\u7edf\u5185\u6838\u5982\u679c\u6709\u6f0f\u6d1e\uff0c\u90a3\u4e48\u5fc5\u7136\u4f1a\u5f71\u54cd\u5230\u5bb9\u5668\u3002<\/p>\n<h1>\u4e09 \u5982\u4f55\u4e3a\u5bb9\u5668\u5b89\u88c5\u64cd\u4f5c\u7cfb\u7edf<\/h1>\n<h2>3.1 UnionFS\uff08\u8054\u5408\u6587\u4ef6\u7cfb\u7edf\uff09\u7684\u7531\u6765<\/h2>\n<p>\u5bb9\u5668\u5c31\u76f8\u5f53\u4e8e\u4e00\u53f0\u865a\u62df\u673a\u561b\uff0c\u6240\u4ee5\u6211\u4eec\u8fd8\u662f\u5bf9\u6bd4\u7740\u6765\u770b\u3002<\/p>\n<p>\u5b89\u88c5\u64cd\u4f5c\u7cfb\u7edf\u7684\u539f\u7406\u672c\u8d28\u5f88\u7b80\u5355\uff0c\u64cd\u4f5c\u7cfb\u7edf\u7684\u5f00\u53d1\u8005\u5728\u4ed6\u4eec\u81ea\u5df1\u7684\u673a\u5668\u4e0a\u628a\u64cd\u4f5c\u7cfb\u7edf\u4ee3\u7801\u5199\u597d\u4e86\u4e4b\u540e\uff0c\u8981\u7ed9\u6211\u4eec\u7528\u3001\u8981\u653e\u5230\u6211\u4eec\u7684\u673a\u5668\u4e0a\u8dd1\u8d77\u6765\uff0c\u600e\u4e48\u505a\uff1f<\/p>\n<ul>\n<li>\n<p>\u7b2c\u4e00\u6b65\uff1a\u64cd\u4f5c\u7cfb\u7edf\u7684\u5f00\u53d1\u8005\u4eec\u4f1a\u628a\u81ea\u5df1\u7f16\u5199\u7684\u64cd\u4f5c\u7cfb\u7edf\u4ee3\u7801\u6253\u5305\u6210\u4e00\u4e2a\u538b\u7f29\u5305\uff0c\u683c\u5f0f\u4e3aiso\uff0c\u79f0\u4e4b\u4e3a\u7cfb\u7edf\u955c\u50cf\uff0c\u955c\u50cf\u987e\u540d\u601d\u4e49\uff0c\u4f60\u53bb\u7167\u955c\u5b50\uff0c\u955c\u5b50\u91cc\u7684\u50cf\u7ed9\u4f60\u662f\u5b8c\u5168\u4e00\u6837\u7684\uff0c\u6240\u4ee5\u7cfb\u7edf\u955c\u50cf\u7684\u610f\u601d\u5c31\u662f\u8bf4\uff0c\u8be5\u6587\u4ef6\u5c31\u662f\u5b8c\u5168\u62f7\u8d1d\u4e86\u5f00\u53d1\u8005\u4eec\u5f00\u53d1\u7684\u64cd\u4f5c\u7cfb\u7edf\u4ee3\u7801\u6587\u4ef6\uff0c\u4e00\u6a21\u4e00\u6837\u3002<\/p>\n<\/li>\n<li>\n<p>\u7b2c\u4e8c\u6b65\uff1a\u628aiso\u6587\u4ef6\u201c\u91ca\u653e\/\u89e3\u538b\u201d\u5230\u76ee\u6807\u4e3b\u673a\uff0c\u8fd9\u5c31\u662f\u5b89\u88c5\u64cd\u4f5c\u7cfb\u7edf\u3002\u5982\u4f55\u91ca\u653e\u5462\uff1f\u5982\u679c\u76ee\u6807\u4f4d\u7f6e\u662f\u4e00\u5757\u88f8\u76d8\uff0c\u90a3\u5c31\u9700\u8981\u501f\u52a9\u4e00\u4e2a\u4f20\u8f93\u4ecb\u8d28\uff0c\u4e5f\u5c31\u662f\u6211\u4eec\u8bf4\u7684U\u542f\u3001\u7cfb\u7edf\u5149\u76d8\u7b49\u4f20\u8f93\u4ecb\u8d28<\/p>\n<\/li>\n<\/ul>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/39.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/39.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u90a3\u5982\u4f55\u4e3a\u5bb9\u5668\u5b89\u88c5\u64cd\u4f5c\u7cfb\u7edf\u5462\uff1f\u539f\u7406\u90fd\u662f\u4e00\u6837\u7684\uff0c\u4f46\u5bf9\u4e8e\u5bb9\u5668\u6765\u8bf4\uff0c\u6211\u4eec\u662f\u60f3\u5728\u5bbf\u4e3b\u673a\u4e0a\u542f\u52a8\u591a\u4e2a\u5bb9\u5668\uff0c\u8ba9\u5b83\u4eec\u62e5\u6709\u64cd\u4f5c\u7cfb\u7edf\uff0c\u6240\u4ee5\u5bbf\u4e3b\u673a\u5c31\u662f\u6211\u4eec\u7684\u4f20\u8f93\u4ecb\u8d28\uff0c\u76ee\u6807\u4f4d\u7f6e\u5c31\u662f\u5bb9\u5668\uff0c\u6211\u4eec\u9700\u8981\u505a\u7684\u5c31\u662f\u628a\u5bb9\u5668\u7684\u955c\u50cf\u4e0b\u8f7d\u5230\u5bbf\u4e3b\u673a\u5c31\u53ef\u4ee5\uff0c\u8ba9\u628a\u5bb9\u5668\u7684\u955c\u50cf\u6587\u4ef6\u5173\u8054\u7ed9\u6bcf\u4e2a\u5bb9\u56681\u5c31\u884c\uff0c\u5982\u679c\u4f60\u60f3\u8ba9\u5bb9\u5668\u6709\u4e0d\u540c\u7684\u7cfb\u7edf\uff0c\u90a3\u5c31\u5173\u8054\u4e0d\u540c\u7684\u955c\u50cf\u5c31\u53ef\u4ee5\uff0c\u4e0d\u540c\u7684\u955c\u50cf\u5c31\u662f\u4e0d\u540c\u7684\u7cfb\u7edf\u561b<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/image-202208161145095581.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/image-202208161145095581.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u4f46\u8bf4\u5230\u8fd9\u91cc\uff0c\u6211\u4eec\u5c31\u9700\u8981\u601d\u8003\u4e00\u4e2a\u95ee\u9898\uff0c\u5bf9\u4e8e\u865a\u62df\u673a\u6765\u8bf4\uff0c\u5b83\u5f88\u7b28\u91cd\uff0c\u6bcf\u4e2a\u865a\u62df\u673a\u8981\u60f3\u62e5\u6709\u81ea\u5df1\u7684\u64cd\u4f5c\u7cfb\u7edf\uff0c\u6211\u4eec\u90fd\u9700\u8981\u628a\u4e00\u4efd\u64cd\u4f5c\u7cfb\u7edf\u955c\u50cf\u7684\u5185\u5b58\u5b8c\u6574\u5730\u62f7\u8d1d\u7ed9\u5b83\uff0c\u5982\u679c\u4e00\u4e2a\u955c\u50cf\u4e3a1G\uff0c\u90e8\u7f72\u4e8610\u53f0\u865a\u62df\u673a\uff0c\u5c31\u9700\u8981\u8017\u8d3910G\u7684\u7a7a\u95f4\uff0c\u800c\u8fd910G\u7684\u5185\u5bb9\u90fd\u662f\u5197\u4f59\u7684\uff0c<\/p>\n<p>\u6240\u4ee5\u5bf9\u4e8e\u5bb9\u5668\u6765\u8bf4\uff0c\u5177\u4f53\u505a\u6cd5\u5e76\u4e0d\u662f\u628a\u5bb9\u5668\u955c\u50cf\u76f4\u63a5\u62f7\u8d1d\u7ed9\u6bcf\u4e2a\u5bb9\u5668\u7684\u540d\u79f0\u7a7a\u95f4\uff0c\u800c\u662f\u901a\u8fc7\u6302\u8f7d\u7684\u65b9\u5f0f\u5b8c\u6210\u7684\uff0c\u800c\u4e14\u662f\u4ee5\u53ea\u8bfb\u7684\u65b9\u5f0f\u6302\u8f7d\u7684\uff0c\u81f3\u4e8e\u5bb9\u5668\u5185\u53ea\u8d1f\u8d23\u5b58\u81ea\u5df1\u65b0\u589e\u7684\u6539\u52a8\u5c31\u53ef\u4ee5\uff0c\u4e0d\u5f71\u54cd\u5176\u4ed6\u5bb9\u5668\uff0c\u8fd9\u5c31\u7528\u5230\u4e86UnionFS\uff08\u8054\u5408\u6587\u4ef6\u7cfb\u7edf\uff09\u6280\u672f\uff0c<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/40.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/40.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>UnionFS\uff08\u8054\u5408\u6587\u4ef6\u7cfb\u7edf\uff09\u8be6\u89e3\u5982\u4e0b<\/p>\n<h2>3.2 \u603b\u7ed3\u540c\u4e00\u4e2a\u955c\u50cf\u542f\u52a8\u591a\u4e2a\u5bb9\u5668\u7684\u672c\u8d28<\/h2>\n<p>\u5bb9\u5668\u7684\u955c\u50cf\u7684\u672c\u8d28\u5c31\u662frootfs\uff0c\u542f\u52a8\u5bb9\u5668\uff0c\u6307\u5b9a\u955c\u50cf\u7684\u610f\u4e49\uff0c\u5c31\u662f\u4e3a\u4e86\u628arootfs\u5171\u4eab\u7ed9\u5bb9\u5668\u7684\u540d\u79f0\u7a7a\u95f4\uff0c\u8fd9\u5c31\u5982\u540c\u7ed9\u5bb9\u5668\u5b89\u88c5\u4e86\u4e00\u4e2a\u64cd\u4f5c\u7cfb\u7edf\u4e00\u6837\u3002\u4f46\u662f\u7b49\u4e00\u7b49\uff0c\u4e3a\u4f55\u6211\u8fd9\u91cc\u7528\u7684\u662f\u5171\u4eab\u8fd9\u4e2a\u8bcd\u5462\uff1f\u955c\u50cf\u7684\u672c\u8d28\u5c31\u662f\u628arootfs\u6253\u5305\u538b\u7f29\u5f97\u5230\u4e00\u4e2a\u538b\u7f29\u5305\uff0c\u90a3\u4e48\u542f\u52a8\u5bb9\u5668\u4e0d\u5e94\u8be5\u662f\u628a\u8be5\u538b\u7f29\u5305\u89e3\u538b\u5230\u8be5\u5bb9\u5668\u7684\u540d\u79f0\u7a7a\u95f4\u5185\u5417\uff1f<\/p>\n<p>\u601d\u8def\u5b8c\u5168\u6b63\u786e\uff0c\u4f46\u5177\u4f53\u64cd\u4f5c\u4e0d\u662f\u8fd9\u6837\u7684\uff01<\/p>\n<p>\u5982\u679c\u771f\u7684\u8fd9\u4e48\u505a\uff0c\u90a3\u5047\u8bbe\u6211\u4eec\u4e00\u4e2a\u955c\u50cf10G\uff0c\u90a3\u4e48\u6211\u4eec\u7528\u8fd9\u540c\u4e00\u4e2a\u955c\u50cf\u542f\u52a810\u4e2a\u5bb9\u5668\uff0c\u5c82\u4e0d\u662f\u8981\u89e3\u538b10\u6b21\uff0c\u6570\u636e\u5197\u4f59\u8fbe\u5230\u4e8650G\uff0c\u592a\u6d6a\u8d39\u4e86\u3002<\/p>\n<p>\u90a3\u5982\u4f55\u89e3\u51b3\u8be5\u95ee\u9898\u5462\uff1f<\/p>\n<p>\u5148\u8bf4\u7b54\u6848\uff1a\u6211\u4e4b\u524d\u63d0\u5230\u7684\u5171\u4eab\u4e00\u6b21\u7684\u610f\u601d\u6307\u7684\u5c31\u662f\uff0c\u6211\u4eec\u7528\u4e00\u4e2a\u955c\u50cf\u542f\u52a8\u5bb9\u5668\uff0c\u5176\u5b9e\u662f\u628a\u8be5\u955c\u50cf\u91cc\u7684\u76ee\u5f55\u90fdmount\u6302\u8f7d\u5230\u4e86\u5bb9\u5668\u540d\u79f0\u7a7a\u95f4\u5185\uff0c\u5e76\u4e14\u8bbe\u7f6e\u4e3a\u53ea\u8bfb\uff08\u5982\u4f55\u5199\u5165\uff0c\u540e\u7eed\u5728\u4ecb\u7ecd\uff09\uff0c\u4e5f\u5c31\u8bf4\uff0c\u6211\u4eec\u7528\u540c\u4e00\u4e2a\u955c\u50cf\u542f\u52a8\u4e8610\u4e2a\u5bb9\u5668\uff0c\u5176\u5b9e\u672c\u8d28\u5c31\u662f\u628a\u8fd9\u4e2a\u955c\u50cf\u91cc\u7684\u76ee\u5f55mount\u7ed9\u4e8610\u4e2a\u5bb9\u5668\u540d\u79f0\u7a7a\u95f4\u800c\u5df2\uff0c\u56e0\u6b64\u5927\u5bb6\u662f\u5171\u4eab\u955c\u50cf\u7684\u3002<\/p>\n<p>ps\uff1a\u4e0enamespace\u8054\u5408\u5728\u4e00\u8d77\u601d\u8003\uff0cnamespace\u4e2d\u9694\u79bb\u7684\u8bf8\u591a\u8d44\u6e90\u4e2d\u5c31\u5305\u62ecmount\u6302\u8f7d\uff0c\u5982\u6b64\uff0c\u54ea\u6015\u662f\u540c\u4e00\u4e2a\u955c\u50cf\uff0cmount\u5230\u4e86\u4e0d\u540c\u7684\u5bb9\u5668\u6216\u8005\u8bf4\u540d\u79f0\u7a7a\u95f4\u91cc\uff0c\u80af\u5b9a\u662f\u4e0e\u5176\u4ed6\u5bb9\u5668\/\u540d\u79f0\u7a7a\u95f4\u9694\u79bb\u7684<\/p>\n<h2>3.3 \u5bb9\u5668\u5185\u5982\u4f55\u5199\u5165\u6570\u636e<\/h2>\n<p>\u4e0a\u4e00\u5c0f\u8282\u63d0\u5230\u591a\u4e2a\u5bb9\u5668\u7528\u4e00\u4e2a\u955c\u50cf\u542f\u52a8\uff0c\u672c\u8d28\u662f\u4ee5<strong>\u53ea\u8bfb\u65b9\u5f0f<\/strong>\u628a\u955c\u50cf\u76ee\u5f55\u90fdmount\u5230\u4e86\u6bcf\u4e2a\u5bb9\u5668\u7684\u540d\u79f0\u7a7a\u95f4\u91cc\u3002\u90a3\u5bb9\u5668\u5185\u5c82\u4e0d\u662f\u90fd\u65e0\u6cd5\u5199\u5165\u6570\u636e\u4e86\uff0c\u4f46\u662f\u6211\u4eec\u660e\u660e\u662f\u53ef\u4ee5\u5728\u5bb9\u5668\u5185\u5199\u5165\u6570\u636e\u7684\u554a\uff1f\u96be\u9053\u8bf4\u4ee5\u53ea\u8bfb\u65b9\u5f0f\u6302\u5728\u955c\u50cf\u662f\u9519\u8bef\u7684\uff1f\u8fd9\u80af\u5b9a\u662f\u6ca1\u9519\u7684\uff0c\u8981\u60f3\u7406\u89e3\u660e\u660e\u542f\u52a8\u5bb9\u5668\u662f\u4ee5\u53ea\u8bfb\u65b9\u5f0f\u628arootfs\u91cc\u5305\u542b\u7684\u76ee\u5f55\u6302\u8f7d\u5230\u5bb9\u5668\u91cc\uff0c\u4f46\u662f\u5374\u53ef\u4ee5\u5728\u5bb9\u5668\u91cc\u6267\u884c\u589e\u5220\u6539\u67e5\u64cd\u4f5c\uff0c\u90a3\u5c31\u9700\u8981\u4e86\u89e3\u4e00\u4e0bUnionFS\u8054\u5408\u6587\u4ef6\u7cfb\u7edf\u3002<\/p>\n<p>\u4ec0\u4e48\u662f\u8054\u5408\u6587\u4ef6\u7cfb\u7edf\uff0c\u5148\u8bf4\u7b54\u6848\uff1a<\/p>\n<p>\u5bb9\u5668\u5185\u7684rootfs\u6839\u6587\u4ef6\u7cfb\u7edf\u7c7b\u578b\uff0c\u5e76\u4e0d\u662f\u5927\u5728\u666e\u901alinux\u8282\u70b9\u4e0a\u770b\u5230\u7684Ext4\u6216\u8005XFS\u4e4b\u7c7b\u7684\u5e38\u89c1\u6587\u4ef6\u7cfb\u7edf\uff0c\u800c\u662fOverlay\uff0c<strong>Overlay\u662f\u4e00\u79cd\u8054\u5408\u6587\u4ef6\u7cfb\u7edfUnionFS\uff08OverlayFS\u7b80\u79f0overlay \u662f UnionFS \u7684\u4e00\u79cd\u5177\u4f53\u5b9e\u73b0\uff0c\u66f4\u591a\u5b9e\u73b0\u8be6\u89e33.8\u5c0f\u8282\uff09<\/strong>\uff0c\u8054\u5408\u6587\u4ef6\u7cfb\u7edf\u987e\u540d\u601d\u4e49\uff0c\u53ef\u4ee5\u628a\u6587\u4ef6\u7cfb\u7edf\u4e0a\u591a\u4e2a\u76ee\u5f55(\u5206\u652f)\u5185\u5bb9\u8054\u5408\u6302\u8f7d\u5230\u540c\u4e00\u4e2a\u76ee\u5f55\u4e0b\uff0c\u4f7f\u7528\u8005\u4e5f\u5c31\u662f\u5bb9\u5668\u770b\u8d77\u6765\u8ba4\u4e3a\u662f\u4e00\u4e2a\u76ee\u5f55\uff0c\u800c\u5b9e\u9645\u4e0a\u5728\u7269\u7406\u673a\u91cc\u662f\u7531\u591a\u4e2a\u76ee\u5f55\u6784\u6210\u7684\u3002<\/p>\n<p>OverlayFS\u4f7f\u7528\u4e24\u4e2a\u76ee\u5f55\uff0c\u628a\u4e00\u4e2a\u76ee\u5f55\u7f6e\u653e\u4e8e\u53e6\u4e00\u4e2a\u4e4b\u4e0a\uff0c\u5e76\u4e14\u5bf9\u5916\u63d0\u4f9b\u5355\u4e2a\u7edf\u4e00\u7684\u89c6\u89d2\u3002\u8fd9\u4e24\u4e2a\u76ee\u5f55\u901a\u5e38\u88ab\u79f0\u4f5c\u5c42\uff0c\u8fd9\u4e2a\u5206\u5c42\u7684\u6280\u672f\u88ab\u79f0\u4f5cunion mount\u3002\u672f\u8bed\u4e0a\uff0c\u4e0b\u5c42\u7684\u76ee\u5f55\u53eb\u505alowerdir\uff0c\u4e0a\u5c42\u7684\u53eb\u505aupperdir\u3002\u5bf9\u5916\u5c55\u793a\u7684\u7edf\u4e00\u89c6\u56fe\u79f0\u4f5cmerged<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/3.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/08\/3.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>lowerdir&#8212;&gt;\u955c\u50cf\u5c42\uff0c\u53ea\u8bfb<\/p>\n<p>upperdir&#8212;-&gt;\u5bb9\u5668\u5c42\uff0c\u4fee\u6539\u76f8\u5173\u7684\u5185\u5bb9\u90fd\u5728\u8fd9\u91cc\u653e\u7740<\/p>\n<p>merged&#8212;-&gt;\u5bb9\u5668\u6620\u5c04\u5c42\uff0c\u6211\u4eec\u5728\u5bb9\u5668\u91cc\u770b\u5230\u7684\u5c31\u662f\u8fd9\u4e00\u5c42\uff0c\u6240\u4ee5\u8be5\u5c42\u4e5f\u53ef\u4ee5\u79f0\u4e4b\u4e3a\u5c55\u73b0\u5c42\u3002<\/p>\n<p>\u9488\u5bf9\u8fd9\u4e09\u5c42\uff0c\u6211\u4eec\u4ece\u4e0b\u5f80\u4e0b\u770b\uff0c\u770b\u5230\u7684merged\u91cc\u7684\u5185\u5bb9\u6765\u81ea\u4e0eupperdir\u4e0elowdir\uff0cupperdir\u91cc\u7684\u5185\u5bb9\u4f1a\u906e\u6321\u4f4flowerdir\u91cc\u7684\u5185\u5bb9\u3002<\/p>\n<p>\u4e86\u89e3<\/p>\n<pre><code>image \u91cc\u9762\u662f\u4e00\u5c42\u5c42\u6587\u4ef6\u7cfb\u7edf\uff0c\u53eb\u505a Union FS\uff08\u8054\u5408\u6587\u4ef6\u7cfb\u7edf\uff09\u3002\u8054\u5408\u6587\u4ef6\u7cfb\u7edf\uff0c\u53ef\u4ee5\u5c06\u51e0\u5c42\u76ee\u5f55\u6302\u8f7d\u5230\u4e00\u8d77\uff0c\u5f62\u6210\u4e00\u4e2a\u865a\u62df\u6587\u4ef6\u7cfb\u7edf\u3002\u865a\u62df\u6587\u4ef6\u7cfb\u7edf\u7684\u76ee\u5f55\u7ed3\u6784\u5c31\u50cf\u666e\u901a linux \u7684\u76ee\u5f55\u7ed3\u6784\u4e00\u6837\uff0cdocker \u901a\u8fc7\u8fd9\u4e9b\u6587\u4ef6\u518d\u52a0\u4e0a\u5bbf\u4e3b\u673a\u7684\u5185\u6838\u63d0\u4f9b\u4e86\u4e00\u4e2a linux \u7684\u865a\u62df\u73af\u5883\u3002\u6bcf\u4e00\u5c42\u6587\u4ef6\u7cfb\u7edf\u6211\u4eec\u53eb\u505a\u4e00\u5c42 layer\uff0c\u8054\u5408\u6587\u4ef6\u7cfb\u7edf\u53ef\u4ee5\u5bf9\u6bcf\u4e00\u5c42\u6587\u4ef6\u7cfb\u7edf\u8bbe\u7f6e\u4e09\u79cd\u6743\u9650\uff0c\u53ea\u8bfb\uff08readonly\uff09\u3001\u8bfb\u5199\uff08readwrite\uff09\u548c\u5199\u51fa\uff08whiteout-able\uff09\uff0c\u4f46\u662f docker \u955c\u50cf\u4e2d\u6bcf\u4e00\u5c42\u6587\u4ef6\u7cfb\u7edf\u90fd\u662f\u53ea\u8bfb\u7684\u3002\n\nlowerDir\uff1a\u6302\u8f7d\u7684\u662f\u955c\u50cf\u5c42\uff0cinit\u91cc\u653e\u7684\u662f\u4e00\u4e9bhosts\u3001hostname\u3001resolv.conf\u6587\u4ef6\uff0c\u56e0\u4e3a\u6bcf\u4e2a\u5bb9\u5668\u542f\u52a8\n        \u80af\u80fd\u6307\u5b9a\u7684\u7f51\u7edc\uff0c\u8fd8\u6709\u4e3b\u673a\u540d\u90fd\u4e0d\u4e00\u6837\uff0c\u6240\u4ee5\u8fd9\u4e9b\u6587\u4ef6\u4f1a\u5355\u72ec\u6302\u8f7d\uff0cdocker\u5f15\u64ce\u542f\u52a8\u65f6\u5019\u4f1a\u52a8\u6001\u4fee\u6539\u4fdd\u8bc1\u6bcf\u4e2a\u5bb9\u5668\n        \u7684\u4e3b\u673a\u540d\u7b49\u4fe1\u606f\u4e0d\u4e00\u6837,\u540e\u9762\u7684diff\u76ee\u5f55\u5c31\u662f\u955c\u50cf\u7684rootfs\uff0c\u6709\u51e0\u4e2a\u5c31\u662f\u4ee3\u8868\u8fd9\u4e2a\u955c\u50cf\u6709\u51e0\u5c42\uff08\u521d\u59cb\u60c5\u51b5\u5c31\u4e00\u5c42\uff0c\n        \u6709\u53ef\u80fd\u8be5\u955c\u50cf\u662f\u522b\u4eba\u57fa\u4e8e\u57fa\u7840\u7684centos\u955c\u50cfcommit\u4e86\u5f88\u591a\u6b21\uff0c\u5373\u88ab\u5236\u4f5c\u4e86\u5f88\u591a\u6b21\uff0c\u90a3\u4e48\u955c\u50cf\u7684\u5c42\u7ea7\u5c31\u4f1a\u5f88\u591a\uff09\n\nupperdir\uff1a\u662f\u5bb9\u5668\u7684\u53ef\u5199\u5c42\uff0c\u6539\u52a8\u7684\u6587\u4ef6\u90fd\u5728\u8fd9\u91cc\n\nupperdir\u7684\u5185\u5bb9+lowerdir\u7684\u5185\u5bb9\u5171\u540c\u6784\u6210\u4e86merged\u7684\u5185\u5bb9\uff0c\u4e00\u5207\u4ee5upperdir\u4e3a\u51c6\uff0c\u6ca1\u6709\u7684\u53bblowerdir\u4e2d\u8981\n                \u5982\u679c\u662f\u8bfb\uff0cupperdir\u4e2d\u6ca1\u6709\u5219\u76f4\u63a5\u8bfblowerdir\n                \u5982\u679c\u662f\u5199\uff0c\u5219\u5c06\u6587\u4ef6\u4ecelowerdir\u4e2d\u62f7\u8d1d\u5230upperdir\u4e2d\u624d\u80fd\u5199\uff0c\u5199\u5b8c\u540e\uff0c\u4e0b\u6b21\u518d\u5199\u5c31\u76f4\u63a5\u4eceupperdir\u4e2d\u53d6\n\n                \u5982\u679c\u662f\u5220\u9664\uff0c\u5219\u5728upperdir\u4e2d\u5c06\u6587\u4ef6\u8bbe\u7f6e\u4e3a\u9690\u85cf\uff0c\u5e76\u4e0d\u4f1a\u771f\u7684\u5220\u9664\u6389lowerdir\u4e2d\u7684\u6587\u4ef6\n                    \u8be6\u89e3\u5982\u4e0b\uff1a\n                        \u5bb9\u5668\u4f1a\u5728\u955c\u50cf\u5c42\u521b\u5efa\u4e00\u4e2awhiteout\u6587\u4ef6\uff0c\u800c\u955c\u50cf\u5c42\u7684\u6587\u4ef6\u5e76\u6ca1\u6709\u5220\u9664\uff0c\u4f46\u662fwhiteout\u6587\u4ef6\u4f1a\u9690\u85cf\u5b83\u3002\n                        \u5bb9\u5668\u4e2d\u5220\u9664\u4e00\u4e2a\u76ee\u5f55\uff0c\u5bb9\u5668\u5c42\u4f1a\u521b\u5efa\u4e00\u4e2a\u4e0d\u900f\u660e\u76ee\u5f55\uff0c\u8fd9\u548cwhiteout\u6587\u4ef6\u9690\u85cf\u955c\u50cf\u5c42\u7684\u6587\u4ef6\u7c7b\u4f3c\n\n                \u5982\u679c\u662f\u91cd\u547d\u540d\u76ee\u5f55 \u53ea\u6709\u5728\u6e90\u6587\u4ef6\u548c\u76ee\u7684\u8def\u5f84\u90fd\u5728\u9876\u5c42\u5bb9\u5668\u5c42upperdir\u65f6\uff0c\u624d\u5141\u8bb8\u6267\u884crename\u64cd\u4f5c<\/code><\/pre>\n<p><strong>\u5bb9\u5668overlay\u8bfb\u5199<\/strong>\u6709\u4e09\u79cd\u573a\u666f<\/p>\n<p>1\u3001lowerdir\u91cc\u6709\uff0cupperdir\u91cc\u6ca1\u6709<\/p>\n<p>\u5bb9\u5668\u4f1a\u901a\u8fc7overlay\u53ea\u8bfb\u8bbf\u95ee\u6587\u4ef6 \u5bb9\u5668\u5c42\u4e0d\u5b58\u5728\u7684\u6587\u4ef6 \u5982\u679c\u5bb9\u5668\u53ea\u8bfb\u6253\u5f00\u4e00\u4e2a\u6587\u4ef6\uff0c\u4f46\u8be5\u5bb9\u5668\u4e0d\u5728\u5bb9\u5668\u5c42(upperdir)\uff0c\u5c31\u8981\u4ece\u955c\u50cf\u5c42(lowerdir)\u4e2d\u8bfb\u53d6\u3002\u8fd9\u4f1a\u5f15\u8d77\u5f88\u5c0f\u7684\u6027\u80fd\u6d88\u8017\u3002<\/p>\n<p>2\u3001lowerdir\u91cc\u6ca1\u6709\uff0cupperdir\u91cc\u6709<\/p>\n<p>\u53ea\u5b58\u5728\u4e8e\u5bb9\u5668\u5c42\u7684\u6587\u4ef6 \u5982\u679c\u5bb9\u5668\u53ea\u8bfb\u6743\u9650\u6253\u5f00\u4e00\u4e2a\u6587\u4ef6\uff0c\u5e76\u4e14\u5bb9\u5668\u53ea\u5b58\u5728\u4e8e\u5bb9\u5668\u5c42(upperdir)\u800c\u4e0d\u662f\u955c\u50cf\u5c42(lowerdir)\uff0c\u90a3\u4e48\u76f4\u63a5\u4ece\u955c\u50cf\u5c42\u8bfb\u53d6\u6587\u4ef6\uff0c\u65e0\u989d\u5916\u7684\u6027\u80fd\u635f\u8017<\/p>\n<p>3\u3001lowerdir\u91cc\u6709\uff0cupperdir\u91cc\u4e5f\u6709<\/p>\n<p>\u6587\u4ef6\u540c\u65f6\u5b58\u5728\u4e8e\u5bb9\u5668\u5c42\u548c\u955c\u50cf\u5c42 \u90a3\u4e48\u4f1a\u8bfb\u53d6\u5bb9\u5668\u5c42\u7684\u6587\u4ef6\uff0c\u56e0\u4e3a\u5bb9\u5668\u5c42(upperdir)\u9690\u5c42\u4e86\u955c\u50cf\u5c42(lowerdir)\u7684\u540c\u540d\u6587\u4ef6\uff0c\u56e0\u6b64\uff0c\u4e5f\u6ca1\u6709\u989d\u5916\u7684\u6027\u80fd\u635f\u8017<\/p>\n<p>\u603b\u7ed3\u4e00\u53e5\u8bdd\u5c31\u662f\uff0clowerdir\u955c\u50cf\u5c42\u91cc\u7684\u5185\u5bb9\u662f\u53ea\u8bfb\u7684\uff08\u53ef\u4ee5\u901a\u8fc7\u6302\u8f7d\u914d\u7f6e\u53ea\u8bfb\uff09\uff0c\u589e\u5220\u6539\u7684\u6587\u4ef6\u90fd\u5199\u5230upperdir\u91cc\uff0cupperdir\u91cc\u7684\u540c\u540d\u6587\u4ef6\u4f1a\u906e\u6321\u4f4flowdir\u91cc\u7684\u5185\u5bb9\u3001\u4f18\u5148\u7ea7\u66f4\u9ad8\uff0clowerdir+upperdir\u8054\u5408\u6302\u8f7d\u5230\u4e86merged\u91cc<\/p>\n<p>\u81f3\u6b64\uff0c\u4f60\u5e94\u8be5\u660e\u767d\uff0c\u955c\u50cf\u5c42\u91cc\u7684\u5185\u5bb9\u80af\u5b9a\u662f\u53ea\u8bfb\u7684\uff0c\u4f46\u662f\u8bfb\u5199\u7684\u5185\u5bb9\u5176\u5b9e\u90fd\u653e\u5230\u4e86upperdir\u91cc\uff0c\u5e76\u4e14\u56e0\u4e3aupperdir\u5bf9lowerdir\u6709\u906e\u6321\u6548\u679c\uff0c\u5728\u5f53\u524d\u5bb9\u5668\u91cc\uff0c\u53ef\u4ee5\u770b\u5230\u4fee\u6539\uff0c\u5728\u5176\u4ed6\u5bb9\u5668\u91cc\u53ef\u80fd\u6ca1\u6709\u4fee\u6539\u3001\u4e8e\u662f\u5728upperdir\u91cc\u770b\u4e0d\u5230\u4fee\u6539\uff0c\u6ca1\u6709\u906e\u6321\uff0c\u5219\u770b\u5230\u7684\u4ecd\u662flowerdir\u91cc\u7684\u5185\u5bb9<\/p>\n<p>\u4e86\u89e3\uff1a<\/p>\n<pre><code>\u6709\u4ee5\u4e0b\u573a\u666f\u5bb9\u5668\u4fee\u6539\u6587\u4ef6 \u7b2c\u4e00\u6b21\u5199\u4e00\u4e2a\u6587\u4ef6\uff0c\u5bb9\u5668\u7b2c\u4e00\u6b21\u5199\u4e00\u4e2a\u5df2\u7ecf\u5b58\u5728\u7684\u6587\u4ef6\uff0c\u5bb9\u5668\u5c42\u4e0d\u5b58\u5728\u8fd9\u4e2a\u6587\u4ef6\u3002overlay\/overlay2\u9a71\u52a8\u6267\u884ccopy-up\u64cd\u4f5c\uff0c\u5c06\u6587\u4ef6\u4ece\u955c\u50cf\u5c42\u62f7\u8d1d\u5230\u5bb9\u5668\u5c42\u3002\u7136\u540e\u5bb9\u5668\u4fee\u6539\u5bb9\u5668\u5c42\u65b0\u62f7\u8d1d\u7684\u6587\u4ef6\n\ncopy-up \u64cd\u4f5c\u53ea\u53d1\u751f\u5728\u7b2c\u4e00\u6b21\u5199\u6587\u4ef6\u65f6\uff0c\u540e\u7eed\u7684\u5bf9\u540c\u4e00\u4e2a\u6587\u4ef6\u7684\u978b\u64cd\u4f5c\u90fd\u662f\u76f4\u63a5\u9488\u5bf9\u62f7\u8d1d\u5230\u5bb9\u5668\u5c42\u7684\u6587\u4ef6\nOverlayFS\u53ea\u5de5\u4f5c\u5728\u4e24\u5c42\u4e2d\u3002\u8fd9\u6bd4AUFS\u8981\u5728\u591a\u5c42\u955c\u50cf\u4e2d\u67e5\u627e\u65f6\u6027\u80fd\u8981\u597d\n\u5220\u9664\u6587\u4ef6\u548c\u76ee\u5f55 \u5220\u9664\u6587\u4ef6\u65f6\uff0c\u5bb9\u5668\u4f1a\u5728\u955c\u50cf\u5c42\u521b\u5efa\u4e00\u4e2awhiteout\u6587\u4ef6\uff0c\u800c\u955c\u50cf\u5c42\u7684\u6587\u4ef6\u5e76\u6ca1\u6709\u5220\u9664\uff0c\u4f46\u662fwhiteout\u6587\u4ef6\u4f1a\u9690\u85cf\u5b83\u3002\u5bb9\u5668\u4e2d\u5220\u9664\u4e00\u4e2a\u76ee\u5f55\uff0c\u5bb9\u5668\u5c42\u4f1a\u521b\u5efa\u4e00\u4e2a\u4e0d\u900f\u660e\u76ee\u5f55\uff0c\u8fd9\u548cwhiteout\u6587\u4ef6\u9690\u85cf\u955c\u50cf\u5c42\u7684\u6587\u4ef6\u7c7b\u4f3c\n\n\u91cd\u547d\u540d\u76ee\u5f55 \u53ea\u6709\u5728\u6e90\u6587\u4ef6\u548c\u76ee\u7684\u8def\u5f84\u90fd\u5728\u9876\u5c42\u5bb9\u5668\u5c42\u65f6\uff0c\u624d\u5141\u8bb8\u6267\u884crename\u64cd\u4f5c\uff0c\u5426\u5219\u8fd4\u56deEXDEV\u3002\u56e0\u6b64\uff0c\u5e94\u7528\u9700\u8981\u80fd\u591f\u5904\u7406EXDEV\uff0c\u5e76\u4e14\u56de\u6eda\u64cd\u4f5c\uff0c\u6267\u884c\u66ff\u4ee3\u7684\u201d\u62f7\u8d1d\u548c\u5220\u9664\u201d\u7b56\u7565<\/code><\/pre>\n<p>\u4e3a\u4f55\u90e8\u7f72docker\u4e0ek8s\u65f6\u5185\u6838\u5efa\u8bae\u5347\u7ea7\u52304.0\u4ee5\u4e0a\uff1aoverlay\u4e0eoverlay2<\/p>\n<pre><code>overlay\u9a71\u52a8\u53ea\u80fd\u5de5\u4f5c\u5728\u4e24\u5c42\u4e4b\u4e0a\uff0c\u4e5f\u5c31\u662f\u8bf4\u591a\u5c42\u955c\u50cf\u4e0d\u80fd\u7528\u591a\u5c42OverlayFS\u5b9e\u73b0\u3002\u66ff\u4ee3\u7684\uff0c\u6bcf\u4e2a\u955c\u50cf\u5c42\u5728\/var\/lib\/docker\/overlay\u4e2d\u7528\u81ea\u5df1\u7684\u76ee\u5f55\u6765\u5b9e\u73b0\uff0c\u4f7f\u7528\u786c\u94fe\u63a5\u8fd9\u79cd\u6709\u6548\u5229\u7528\u7a7a\u95f4\u7684\u65b9\u6cd5\uff0c\u6765\u5f15\u7528\u5e95\u5c42\u5206\u4eab\u7684\u6570\u636e\u3002\n\n\u6ce8\u610f: Docker1.10\u4e4b\u540e\uff0c\u955c\u50cf\u5c42ID\u548c\/var\/lib\/docker\u4e2d\u7684\u76ee\u5f55\u540d\u4e0d\u518d\u4e00\u4e00\u5bf9\u5e94\n\n\u521b\u5efa\u4e00\u4e2a\u5bb9\u5668\uff0coverlay\u9a71\u52a8\u8054\u5408\u955c\u50cf\u5c42\u548c\u4e00\u4e2a\u65b0\u76ee\u5f55\u7ed9\u5bb9\u5668\u3002\u955c\u50cf\u9876\u5c42\u4e2d\u7684overlay\u662f\u53ea\u8bfblowerdir\uff0c\u5bb9\u5668\u7684\u65b0\u76ee\u5f55\u662f\u53ef\u5199\u7684upperdir\n\nOverlayFS \uff08overlay2\uff09\u955c\u50cf\u5206\u5c42\u4e0e\u5171\u4eaboverlay\u9a71\u52a8\u53ea\u5de5\u4f5c\u5728\u4e00\u4e2alower OverlayFS\u5c42\u4e4b\u4e0a\uff0c\u56e0\u6b64\u9700\u8981\u786c\u94fe\u63a5\u6765\u5b9e\u73b0\u591a\u5c42\u955c\u50cf\uff0c\u4f46overlay2\u9a71\u52a8\u539f\u751f\u5730\u652f\u6301\u591a\u5c42lower OverlayFS\u955c\u50cf(\u6700\u591a128\u5c42)\u3002\u56e0\u6b64overlay2\u9a71\u52a8\u5728\u5408\u5c42\u76f8\u5173\u7684\u547d\u4ee4(\u5982build\u4f55commit)\u4e2d\u63d0\u4f9b\u4e86\u66f4\u597d\u7684\u6027\u80fd\uff0c\u4e0eoverlay\u9a71\u52a8\u5bf9\u6bd4\uff0c\u51cf\u5c11\u4e86inode\u6d88\u8017\n\n\u5728Docker\u4e2d\u914d\u7f6eoverlay2 \u5b58\u50a8\u9a71\u52a8\u4e3a\u4e86\u7ed9Docker\u914d\u7f6eoverlay\u5b58\u50a8\u9a71\u52a8\uff0c\u4f60\u7684Docker host\u5fc5\u987b\u5728Linux kernel3.18\u7248\u672c\u4e4b\u4e0a\uff0c\u5e76\u4e14\u52a0\u8f7d\u4e86overlay\u5185\u6838\u9a71\u52a8\u3002\u5bf9\u4e8eoverlay2\u9a71\u52a8\uff0ckernel\u7248\u672c\u5fc5\u987b\u57284.0\u6216\u4ee5\u4e0a\u3002OverlayFS\u53ef\u4ee5\u8fd0\u884c\u5728\u5927\u591a\u6570Linux\u6587\u4ef6\u7cfb\u7edf\u4e4b\u4e0a\u3002\n\n\u9488\u5bf9overlay2\u5c0f\u7ed3overlay2\u5b58\u50a8\u9a71\u52a8\u5df2\u7ecf\u6210\u4e3a\u4e86Docker\u9996\u9009\u5b58\u50a8\u9a71\u52a8\uff0c\u5e76\u4e14\u6027\u80fd\u4f18\u4e8eAUFS\u548cdevicemapper\u3002\u4e0d\u8fc7\uff0c\u4e5f\u5e26\u6765\u4e86\u4e00\u4e9b\u4e0e\u5176\u4ed6\u6587\u4ef6\u7cfb\u7edf\u4e0d\u517c\u5bb9\u6027\uff0c\u5982\u5bf9open\u548crename\u64cd\u4f5c\u7684\u652f\u6301\uff0c\u53e6\u5916\uff0coverlay\u548coverlay2\u76f8\u6bd4\uff0coverlay2\u652f\u6301\u4e86\u591a\u5c42\u955c\u50cf\uff0c\u4f18\u5316\u4e86inode\u7684\u4f7f\u7528\u3002\n\n\u914d\u7f6edocker\u4f7f\u7528overlay2\n\u5c06\u914d\u7f6e\u6301\u4e45\u5316\u5230\u914d\u7f6e\u6587\u4ef6\/etc\/docker\/daemon.json\u4e2d\n&quot;storage-driver&quot;:&quot;overlay2&quot;\n\n[root@yq01-aip-aikefu19 ~]# docker info |grep overlay\n Storage Driver: overlay2<\/code><\/pre>\n<p>\u63a8\u8350\u9605\u8bfb\uff1a<a href=\"https:\/\/www.cnblogs.com\/linhaifeng\/p\/16443917.html\">https:\/\/www.cnblogs.com\/linhaifeng\/p\/16443917.html<\/a><\/p>\n<h2>3.4 \u8054\u5408\u6587\u4ef6\u7cfb\u7edf\u6302\u8f7d\u5b9e\u9a8c<\/h2>\n<pre><code># 1\u3001\u8054\u5408\u6302\u8f7d\nmkdir -p \/test\/lower1\nmkdir -p \/test\/lower2\nmkdir -p \/test\/lower3\nmkdir -p \/test\/upperdir\nmkdir -p \/test\/work\nmkdir \/test\/merged\n\necho 111 &gt; \/test\/lower1\/1.txt\necho 222 &gt; \/test\/lower2\/2.txt\necho 333 &gt; \/test\/lower3\/3.txt\n\nmount -t overlay overlay -o lowerdir=\/test\/lower1:\/test\/lower2:\/test\/lower3,upperdir=\/test\/upperdir,workdir=\/test\/work \/test\/merged\n\n# 2\u3001\u67e5\u770b\u6302\u8f7d\n[root@yq01-aip-aikefu19 ~]# df\noverlay         94465716  81721684  12727648  87% \/test\/merged\n\n# 3\u3001\u67e5\u770bmerge\u76ee\u5f55\n[root@yq01-aip-aikefu19 ~]# ls \/test\/merged\/\n1.txt  2.txt  3.txt\n\n# 4\u3001\u4fee\u6539\n[root@yq01-aip-aikefu19 ~]# cd \/test\/merged\/\n[root@yq01-aip-aikefu19 merged]# echo 666 &gt; 1.txt \n[root@yq01-aip-aikefu19 merged]# cat 1.txt \n666\n\n# \u7136\u540e\u6211\u4eec\u53bb\u67e5\u770blowerdir\uff0c\u731c\u4e00\u4e0b\uff0c1.txt\u6539\u4e86\u6ca1\u6709\uff0c\u80af\u5b9a\u6ca1\u6539\u554a\n[root@yq01-aip-aikefu19 merged]# cat \/test\/lower1\/1.txt \n111\n# \u4fee\u6539\u7684\u5185\u5bb9\u90fd\u5728upperdir\u91cc\n[root@yq01-aip-aikefu19 merged]# cat \/test\/upperdir\/1.txt \n666\n\n# \u6211\u4eec\u5728merged\u76ee\u5f55\u4e0b\u65b0\u589e\u6587\u4ef6\uff0c\u672c\u8d28\u4e5f\u90fd\u662f\u5efa\u7acb\u5230\u4e86upperdir\u91cc\n[root@yq01-aip-aikefu19 merged]# cd \/test\/merged\/\n[root@yq01-aip-aikefu19 merged]# echo 444 &gt; 4.txt\n[root@yq01-aip-aikefu19 merged]# ls\n1.txt  2.txt  3.txt  4.txt\n[root@yq01-aip-aikefu19 merged]# ls \/test\/upperdir\/\n1.txt  4.txt\n[root@yq01-aip-aikefu19 merged]# \n[root@yq01-aip-aikefu19 merged]# ls \/test\/lower1\/\n1.txt\n[root@yq01-aip-aikefu19 merged]# ls \/test\/lower2\/\n2.txt\n[root@yq01-aip-aikefu19 merged]# ls \/test\/lower3\/\n3.txt\n\n# \u5728merge\u76ee\u5f55\u4e0b\u5220\u9664\u6587\u4ef6\n[root@yq01-aip-aikefu19 merged]# rm -rf 2.txt \n[root@yq01-aip-aikefu19 merged]# \n[root@yq01-aip-aikefu19 merged]# ls -l \/test\/upperdir\/\ntotal 8\n-rw-r--r-- 1 root root    4 Jun 28 15:47 1.txt\nc--------- 1 root root 0, 0 Jun 28 15:50 2.txt  # \u5728upperdir\u91cc\u65b0\u5efa\u4e00\u4e2a\u7279\u6b8a\u6587\u4ef6\u6765\u544a\u8bc9OverlayFS\u8fd9\u4e2a\u6587\u4ef6\u4e0d\u80fd\u51fa\u73b0\u5728merged\u91cc\uff0c\u5373\u4ee3\u8868\u5b83\u5df2\u7ecf\u88ab\u5220\u9664\u4e86\n-rw-r--r-- 1 root root    4 Jun 28 15:50 4.txt<\/code><\/pre>\n<p>\u603b\u7ed3\uff1a<\/p>\n<p>\u6211\u4eec\u53ef\u4ee5\u770b\u5230\uff0cOverlayFS \u7684\u4e00\u4e2a mount \u547d\u4ee4\u7275\u6d89\u5230\u56db\u7c7b\u76ee\u5f55\uff0c\u5206\u522b\u662f lower\uff0cupper\uff0c merged \u548c work\uff0c\u90a3\u5b83\u4eec\u662f\u4ec0\u4e48\u5173\u7cfb\u5462?<\/p>\n<p>1\u3001\u9996\u5148\uff0c\u6700\u4e0b\u9762\u7684&quot;lower\/&quot;\uff0c\u4e5f\u5c31\u662f\u88ab mount \u4e24\u5c42\u76ee\u5f55\u4e2d\u5e95\u4e0b\u7684\u8fd9\u5c42(lowerdir)\u3002<\/p>\n<p>\u5728 OverlayFS \u4e2d\uff0c\u6700\u5e95\u4e0b\u8fd9\u4e00\u5c42\u91cc\u7684\u6587\u4ef6\u662f\u4e0d\u4f1a\u88ab\u4fee\u6539\u7684\uff0c\u4f60\u53ef\u4ee5\u8ba4\u4e3a\u5b83\u662f\u53ea\u8bfb\u7684\/ro\u3002\u6211\u8fd8 \u60f3\u63d0\u9192\u4f60\u4e00\u70b9\uff0c\u5728\u8fd9\u4e2a\u4f8b\u5b50\u91cc\u6211\u4eec\u53ea\u6709\u4e00\u4e2a lower\/ \u76ee\u5f55\uff0c\u4e0d\u8fc7 OverlayFS \u662f\u652f\u6301\u591a\u4e2a lowerdir \u7684\u3002<\/p>\n<p>2\u3001\u7136\u540e\u6211\u4eec\u770b&quot;uppder\/&quot;\uff0c\u5b83\u662f\u88ab mount \u4e24\u5c42\u76ee\u5f55\u4e2d\u4e0a\u9762\u7684\u8fd9\u5c42 (upperdir)\u3002\u5728 OverlayFS \u4e2d\uff0c\u5982\u679c\u6709\u6587\u4ef6\u7684\u521b\u5efa\uff0c\u4fee\u6539\uff0c\u5220\u9664\u64cd\u4f5c\uff0c\u90a3\u4e48\u90fd\u4f1a\u5728\u8fd9\u4e00\u5c42\u53cd\u6620\u51fa\u6765\uff0c\u5b83\u662f \u53ef\u8bfb\u5199\u7684\/rw\u3002<\/p>\n<p>3\u3001\u63a5\u7740\u662f\u6700\u4e0a\u9762\u7684&quot;merged&quot; \uff0c\u5b83\u662f\u6302\u8f7d\u70b9(mount point)\u76ee\u5f55\uff0c\u4e5f\u662f\u7528\u6237\u770b\u5230\u7684\u76ee\u5f55\uff0c \u7528\u6237\u7684\u5b9e\u9645\u6587\u4ef6\u64cd\u4f5c\u5728\u8fd9\u91cc\u8fdb\u884c\u3002<\/p>\n<p>4\u3001\u5176\u5b9e\u8fd8\u6709\u4e00\u4e2a&quot;work\/&quot;\uff0c\u8fd9\u4e2a\u76ee\u5f55\u6ca1\u6709\u5728\u8fd9\u4e2a\u56fe\u91cc\uff0c\u5b83\u53ea\u662f\u4e00\u4e2a\u5b58\u653e\u4e34\u65f6\u6587\u4ef6\u7684\u76ee\u5f55\uff0c OverlayFS \u4e2d\u5982\u679c\u6709\u6587\u4ef6\u4fee\u6539\uff0c\u5c31\u4f1a\u5728\u4e2d\u95f4\u8fc7\u7a0b\u4e2d\u4e34\u65f6\u5b58\u653e\u6587\u4ef6\u5230\u8fd9\u91cc\u3002<\/p>\n<pre><code>\u6211\u4eec\u6700\u4e3b\u8981\u7684\u5185\u5bb9\u662f\u7406\u89e3\u5bb9\u5668\u6587\u4ef6\u7cfb\u7edf\u3002\u4e3a\u4ec0\u4e48\u8981\u6709\u5bb9\u5668\u81ea\u5df1\u7684\u6587\u4ef6\u7cfb\u7edf?\u5f88\u91cd\u8981\u7684\u4e00\u70b9\u662f\u51cf\u5c11\u76f8\u540c\u955c\u50cf\u6587\u4ef6\u5728\u540c\u4e00\u4e2a\u8282\u70b9\u4e0a\u7684\u6570\u636e\u5197\u4f59\uff0c\u53ef\u4ee5\u8282\u7701\u78c1\u76d8\u7a7a\u95f4\uff0c\u4e5f\u53ef\u4ee5\u51cf \u5c11\u955c\u50cf\u6587\u4ef6\u4e0b\u8f7d\u5360\u7528\u7684\u7f51\u7edc\u8d44\u6e90\u3002\n\u4f5c\u4e3a\u5bb9\u5668\u6587\u4ef6\u7cfb\u7edf\uff0cUnionFS \u901a\u8fc7\u591a\u4e2a\u76ee\u5f55\u6302\u8f7d\u7684\u65b9\u5f0f\u5de5\u4f5c\u3002OverlayFS \u5c31\u662f UnionFS \u7684\u4e00\u79cd\u5b9e\u73b0\uff0c\u662f\u76ee\u524d\u4e3b\u6d41 Linux \u53d1\u884c\u7248\u672c\u4e2d\u7f3a\u7701\u4f7f\u7528\u7684\u5bb9\u5668\u6587\u4ef6\u7cfb\u7edf\u3002\nOverlayFS \u4e5f\u662f\u628a\u591a\u4e2a\u76ee\u5f55\u5408\u5e76\u6302\u8f7d\uff0c\u88ab\u6302\u8f7d\u7684\u76ee\u5f55\u5206\u4e3a\u4e24\u5927\u7c7b:lowerdir \u548c upperdir\u3002\nlowerdir \u5141\u8bb8\u6709\u591a\u4e2a\u76ee\u5f55\uff0c\u5728\u88ab\u6302\u8f7d\u540e\uff0c\u8fd9\u4e9b\u76ee\u5f55\u91cc\u7684\u6587\u4ef6\u90fd\u662f\u4e0d\u4f1a\u88ab\u4fee\u6539\u6216\u8005\u5220\u9664\u7684\uff0c \u4e5f\u5c31\u662f\u53ea\u8bfb\u7684;upperdir \u53ea\u6709\u4e00\u4e2a\uff0c\u4e0d\u8fc7\u8fd9\u4e2a\u76ee\u5f55\u662f\u53ef\u8bfb\u5199\u7684\uff0c\u6302\u8f7d\u70b9\u76ee\u5f55\u4e2d\u7684\u6240\u6709\u6587\u4ef6 \u4fee\u6539\u90fd\u4f1a\u5728 upperdir \u4e2d\u53cd\u6620\u51fa\u6765\u3002\n\u5bb9\u5668\u7684\u955c\u50cf\u6587\u4ef6\u4e2d\u5404\u5c42\u6b63\u597d\u4f5c\u4e3a OverlayFS \u7684 lowerdir \u7684\u76ee\u5f55\uff0c\u7136\u540e\u52a0\u4e0a\u4e00\u4e2a\u7a7a\u7684 upperdir \u4e00\u8d77\u6302\u8f7d\u597d\u540e\uff0c\u5c31\u7ec4\u6210\u4e86\u5bb9\u5668\u7684\u6587\u4ef6\u7cfb\u7edf\u3002\n\u6709\u65f6\u5019\u6211\u4eec\u4f1a\u53d1\u73b0\u5728\u5bb9\u5668\u4e2d\u8bfb\u5199\u6587\u4ef6\u600e\u4e48\u53d8\u6162\u4e86\uff1f\uff1f\uff1f\nOverlayFS \u5728 Linux \u5185\u6838\u4e2d\u8fd8\u5728\u4e0d\u65ad\u7684\u5b8c\u5584\uff0c\u5728 kenel 5.4 \u4e2d\uff0cLinux \u4e3a\u4e86\u5b8c\u5584 OverlayFS\uff0c\u589e\u52a0\u4e86 OverlayFS \u81ea\u5df1\u7684 read\/write \u51fd\u6570\u63a5\u53e3\uff0c\u4ece\u800c\u4e0d\u518d\u76f4\u63a5\u8c03\u7528 OverlayFS \u540e\u7aef\u6587\u4ef6\u7cfb\u7edf(\u6bd4\u5982 XFS\uff0cExt4)\u7684 \u8bfb\u5199\u63a5\u53e3\u3002\u4f46\u662f\u5b83\u53ea\u5b9e\u73b0\u4e86\u540c\u6b65 I\/O(sync I\/O)\uff0c\u5e76\u6ca1\u6709\u5b9e\u73b0\u5f02\u6b65 I\/O\n\u5373\u5728 kenel 5.4 \u4e2d\u5bf9 \u5f02\u6b65 I\/O \u64cd\u4f5c\u7684\u662f\u7f3a\u5931\u7684\uff0c\n\u800c\u5728 fio \u505a\u6587\u4ef6\u7cfb\u7edf\u6027\u80fd\u6d4b\u8bd5\u7684\u65f6\u5019\u4f7f\u7528\u7684\u662f\u5f02\u6b65 I\/O\uff0c\u8fd9\u6837\u624d\u53ef\u4ee5\u5f97\u5230\u6587\u4ef6\u7cfb\u7edf\u7684\u6027\u80fd\u6700 \u5927\u503c\u3002\u6240\u4ee5\uff0c\u5728\u5185\u6838 5.4 \u4e0a\u5c31\u65e0\u6cd5\u5bf9 OverlayFS \u6d4b\u51fa\u6700\u9ad8\u7684\u6027\u80fd\u6307\u6807\u4e86\u3002\n\u8fd9\u4e5f\u662f\u6211\u4eec\u5728\u4f7f\u7528\u5bb9\u5668\u6587\u4ef6\u7cfb\u7edf\u7684\u65f6\u5019\u9700\u8981\u6ce8\u610f\u7684\u3002<\/code><\/pre>\n<h2>3.5 \u67e5\u770b\u4e00\u4e2a\u5bb9\u5668\u7684\u6302\u8f7d\u60c5\u51b5<\/h2>\n<div id=\"rml_readmorelogin_placeholder\" style=\"position:relative;\"><div id=\"rml_fade_content\" style=\"position: absolute;\r\ntop:-10em;\r\nwidth:100%;\r\nheight:10em;\r\nbackground: -webkit-linear-gradient(rgba(255, 255, 255, 0) 0%,#ffffff 100%);\r\nbackground-image: -moz-linear-gradient(rgba(255, 255, 255, 0) 0%,#ffffff 100%);\r\nbackground-image: -o-linear-gradient(rgba(255, 255, 255, 0) 0%,#ffffff 100%);\r\nbackground-image: linear-gradient(rgba(255, 255, 255, 0) 0%,#ffffff 100%);\r\nbackground-image: -ms-linear-gradient(rgba(255, 255, 255, 0) 0%,#ffffff 100%);\"><\/div><div class=\"wpf-controller aru_rml_from_in_post\" style=\"background-color:#eeeeee;border:5px solid #cce6ff;\" id=\"ARU_ReadMoreLogin_ReadMoreLoginController\"><h2 id=\"Header\">\u67e5\u770b\u66f4\u591a<\/h2><div id=\"Message\"><p>\u8054\u7cfb\u7ba1\u7406\u5458\u5fae\u4fe1tutu19192010\uff0c\u6ce8\u518c\u8d26\u53f7<\/p>\n<\/div><div id=\"StatusBarHeader\"><\/div><form id=\"ARU_ReadMoreLogin_ReadMoreLoginController\"><input name=\"post_id\" value=\"7326\" type=\"hidden\"\/><input name=\"_init_callback\" value=\"InitLogin\" type=\"hidden\"\/><input name=\"post_id\" value=\"7326\" type=\"hidden\"\/><input name=\"rt_ype\" value=\"1\" type=\"hidden\"\/><input name=\"nonce\" value=\"d5beb63f38\" type=\"hidden\"\/><input name=\"_wpnonce\" value=\"b0e6d8f8bf\" type=\"hidden\"\/><input name=\"_controller\" value=\"ARU_ReadMoreLogin\\ReadMoreLoginController\" type=\"hidden\"\/><input name=\"_proxy_controller\" value=\"ARU_ReadMoreLogin\\ReadMoreLoginController\" type=\"hidden\"\/><input name=\"_view\" value=\"ARU_ReadMoreLogin\\ReadMoreLoginView\" type=\"hidden\"\/><table class=\"wpf-table-placeholder\"><tbody class=\"wpf-table-placeholder\"><tr class=\"wpf-table-placeholder\"><td class=\"wpf-table-placeholder-input\" width=\"400px\"><table class=\"wpf-table-placeholder\"><tbody class=\"wpf-table-placeholder\"><tr class=\"wpf-table-placeholder\"><th class=\"wpf-table-placeholder-input\"><label class=\"wpf-label\">Username:<\/label><\/th><\/tr><tr class=\"wpf-table-placeholder\"><td class=\"wpf-table-placeholder-input\"><input class=\"regular-text text_input\" name=\"username\" value=\"\" type=\"text\"\/><\/td><\/tr><tr class=\"wpf-table-placeholder\"><th class=\"wpf-table-placeholder-input\"><label class=\"wpf-label\">Password:<\/label><\/th><\/tr><tr class=\"wpf-table-placeholder\"><td class=\"wpf-table-placeholder-input\"><input class=\"regular-text text_input\" name=\"password\" value=\"\" type=\"password\"\/><\/td><\/tr><\/tbody><\/table><p class=\"wpf-table-placeholder submit\"><button class=\"wp_plugin_framework_ajax_button\" type=\"button\" style=\"background-color:#4D90FE;;color:#ffffff;;border:1px solid #3079ed;\" name=\"_event\" value=\"ButtonLogin\">Log in<\/button><\/p><\/td><td class=\"wpf-table-placeholder-input\"><\/td><\/tr><\/tbody><\/table><\/form><div id=\"ButtonStartRegister\"><a href=\"https:\/\/egonlin.com\/wp-login.php?action=register\">Register<\/a><\/div><div id=\"Link1\"><a href=\"https:\/\/egonlin.com\/wp-login.php?action=lostpassword\">Forgotten username or password?<\/a><\/div><div id=\"StatusBarFooter\"><\/div><\/div><\/div><div id=aru_remaining_content><\/div>","protected":false},"excerpt":{"rendered":"<p>\u5bb9\u5668\u7684\u955c\u50cf\u6784\u6210\u76f4\u63a5\u5173\u7cfb\u5230\u4f60\u5bf9\u542f\u52a8\u4e00\u4e2a\u5bb9\u5668\u7684\u7406\u89e3 \uff0c\u975e\u5e38\u91cd\u8981 \u4e00 \u5f15\u5165\u95ee\u9898 \u6bcf\u542f\u52a8\u4e00\u4e2a\u5bb9\u5668\uff0c\u5728\u5bb9\u5668\u5185\u90fd\u6709\u4e00\u4e2a\u64cd\u4f5c [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[423,422],"tags":[],"_links":{"self":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts\/7326"}],"collection":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=7326"}],"version-history":[{"count":0,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts\/7326\/revisions"}],"wp:attachment":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=7326"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=7326"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=7326"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}