{"id":18442,"date":"2025-07-15T09:46:21","date_gmt":"2025-07-15T01:46:21","guid":{"rendered":"https:\/\/92it.top\/?p=18442"},"modified":"2025-07-15T09:46:21","modified_gmt":"2025-07-15T01:46:21","slug":"%e4%b8%80%e6%96%87%e7%9c%8b%e6%87%82-linux-%e7%9a%84-buffer-%e5%92%8c-cache%ef%bc%8c%e5%88%b0%e5%ba%95%e6%9c%89%e5%95%a5%e5%8c%ba%e5%88%ab%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/92it.top\/?p=18442","title":{"rendered":"\u4e00\u6587\u770b\u61c2 Linux \u7684 Buffer \u548c Cache\uff0c\u5230\u5e95\u6709\u5565\u533a\u522b\uff1f"},"content":{"rendered":"\n

\u8f6c\u8f7d\uff1a\u4e00\u6587\u770b\u61c2 Linux \u7684 Buffer \u548c Cache\uff0c\u5230\u5e95\u6709\u5565\u533a\u522b\uff1f<\/a><\/p>\n\n\n\n

\u201c\u4e3a\u5565\u6211 free \u547d\u4ee4\u770b\u5185\u5b58\u7528\u5f97\u8fd9\u4e48\u591a\uff0c\u4f46\u7cfb\u7edf\u5374\u4e0d\u6162\uff1f\u201d
\u201cBuffer \u548c Cache \u662f\u4e0d\u662f\u90fd\u53ef\u4ee5\u91ca\u653e\uff1f\u201d
\u201cLinux \u662f\u4e0d\u662f\u5077\u4e86\u6211\u7684\u5185\u5b58\uff1f\u201d<\/pre>\n\n\n\n
\u5f88\u591a\u521a\u63a5\u89e6 Linux \u7684\u4eba\u770b\u5230\u7cfb\u7edf\u5185\u5b58\u7684\u4f7f\u7528\u60c5\u51b5\u65f6\uff0c\u90fd\u4f1a\u4e00\u8138\u7591\u60d1\u3002
\u4eca\u5929\u8fd9\u7bc7\u6587\u7ae0\uff0c\u5c31\u6765\u4e00\u6b21\u6027\u8bb2\u6e05\u695a\u2014\u2014Buffer \u548c Cache \u5230\u5e95\u6709\u5565\u533a\u522b\uff1f<\/strong><\/p>\n\n\n\n
\u3000\u3000<\/p>\n\n\n\n
\ud83d\udd0d \u4e00\u3001\u5148\u770b free \u547d\u4ee4\u8f93\u51fa<\/strong><\/p>\n\n\n\n
\n\n\n\n
$ free -h\n              total        used        free      shared  buff\/cache   available\nMem:           16Gi       2.3Gi       1.2Gi       200Mi        12Gi        13Gi<\/pre>\n\n\n\n
\u4f60\u53ef\u80fd\u4f1a\u60ca\u8bb6\u5730\u53d1\u73b0\uff1a<\/p>\n\n\n\n
    \ud83e\udd14 \u201c\u600e\u4e48\u6211 16G \u7684\u5185\u5b58\uff0cbuff\/cache \u5c31\u5360\u4e86 12G\uff1f\uff01\u201d<\/pre>\n\n\n\n
\u522b\u6025\uff0c\u5176\u5b9e\u8fd9\u662f\u00a0Linux \u7684\u201c\u806a\u660e\u7528\u6cd5\u201d<\/strong>\uff0c\u5e76\u4e0d\u4ee3\u8868\u771f\u7684\u5360\u7528\u3002<\/p>\n\n\n\n
 \u3000<\/p>\n\n\n\n
\ud83e\uddf1 \u4e8c\u3001\u4ec0\u4e48\u662f Buffer\uff1f<\/strong><\/p>\n\n\n\n
\n\n\n\n
\u2705 Buffer \u662f\u4e3a\u4e86\u52a0\u901f\u201c\u5199\u78c1\u76d8\u201d\uff01<\/p>\n\n\n\n
    \n
  • \u2022\u00a0\u6570\u636e\u5199\u5165\u78c1\u76d8<\/strong>\u901a\u5e38\u6bd4\u8f83\u6162<\/li>\n\n\n\n
  • \u2022 Linux \u4f1a\u5148\u628a\u5199\u5165\u6570\u636e\u6682\u65f6\u5b58\u653e\u5728\u5185\u5b58\u4e2d<\/strong>\uff08\u5c31\u662f Buffer\uff09<\/li>\n\n\n\n
  • \u2022 \u7b49\u5f85\u7cfb\u7edf\u7a7a\u95f2\u65f6\uff0c\u6279\u91cf\u5199\u5165\u78c1\u76d8\uff08\u63d0\u9ad8\u6027\u80fd\uff09<\/li>\n<\/ul>\n\n\n\n
    \ud83d\udccc \u4e3e\u4e2a\u4f8b\u5b50\uff1a<\/p>\n\n\n\n
    \u4f60 cp \u4e86\u4e00\u4e2a\u5927\u6587\u4ef6\uff0cLinux \u5148\u653e\u5230 Buffer \u91cc\uff0c\u7b49\u7a0d\u540e\u4e00\u8d77\u5199\u5230\u786c\u76d8\u3002<\/pre>\n\n\n\n
     \u3000<\/p>\n\n\n\n
    \ud83e\udde0 \u4e09\u3001\u4ec0\u4e48\u662f Cache\uff1f<\/strong><\/p>\n\n\n\n
    \n\n\n\n
    \u2705 Cache \u662f\u4e3a\u4e86\u52a0\u901f\u201c\u8bfb\u78c1\u76d8\u201d\uff01<\/p>\n\n\n\n
      \n
    • \u2022 \u5982\u679c\u4f60\u8bbf\u95ee\u8fc7\u67d0\u4e2a\u6587\u4ef6\uff0cLinux \u4f1a\u628a\u5b83\u7f13\u5b58\u5230\u5185\u5b58\u4e2d<\/strong><\/li>\n\n\n\n
    • \u2022 \u4e0b\u6b21\u8bbf\u95ee\u65f6\uff0c\u76f4\u63a5\u4ece\u5185\u5b58\u4e2d\u8bfb\u53d6<\/strong>\uff0c\u901f\u5ea6\u98de\u5feb<\/li>\n\n\n\n
    • \u2022 \u8fd9\u90e8\u5206\u5c31\u662f\u00a0Page Cache<\/strong>\uff0c\u901a\u5e38\u5c31\u53eb Cache<\/li>\n<\/ul>\n\n\n\n
      \ud83d\udccc \u4e3e\u4e2a\u4f8b\u5b50\uff1a<\/p>\n\n\n\n
      \u4f60 cat \u4e86\u4e00\u4e2a\u65e5\u5fd7\u6587\u4ef6\uff0cLinux \u4f1a\u628a\u5b83\u7f13\u5b58\u5230 Cache \u4e2d\uff0c\u4e0b\u4e00\u6b21\u5c31\u4e0d\u518d\u4ece\u78c1\u76d8\u8bfb\u3002<\/pre>\n\n\n\n
       \u3000<\/p>\n\n\n\n
      \ud83d\udd0d \u56db\u3001Buffer \u548c Cache \u7684\u672c\u8d28\u533a\u522b<\/strong><\/p>\n\n\n\n
      \n\n\n\n
      \u5bf9\u6bd4\u9879<\/td>Buffer<\/td>Cache<\/td><\/tr><\/thead>
      \u4e3b\u8981\u4f5c\u7528<\/td>\u5199\u5165\u6570\u636e\u7684\u4e34\u65f6\u7f13\u51b2\u533a<\/td>\u8bfb\u53d6\u6570\u636e\u7684\u7f13\u5b58\u533a<\/td><\/tr>
      \u4f7f\u7528\u573a\u666f<\/td>\u5199\u78c1\u76d8\u4f18\u5316<\/td>\u8bfb\u78c1\u76d8\u4f18\u5316<\/td><\/tr>
      \u7c7b\u578b<\/td>\u5757\u8bbe\u5907\u7f13\u5b58\uff08block device\uff09<\/td>\u6587\u4ef6\u7cfb\u7edf\u7f13\u5b58\uff08page cache\uff09<\/td><\/tr>
      \u751f\u547d\u5468\u671f<\/td>\u5199\u5165\u5b8c\u5c31\u53ef\u4ee5\u91ca\u653e<\/td>\u53ef\u80fd\u957f\u671f\u9a7b\u7559\uff0c\u76f4\u5230\u5185\u5b58\u7d27\u5f20<\/td><\/tr>
      \u662f\u5426\u53ef\u91ca\u653e<\/td>\u662f\uff0c\u7cfb\u7edf\u4f1a\u6839\u636e\u5185\u5b58\u538b\u529b\u52a8\u6001\u56de\u6536<\/td>\u662f\uff0c\u56de\u6536\u673a\u5236\u540c\u6837\u5b58\u5728<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
       \u3000<\/p>\n\n\n\n
      \ud83e\uddea \u4e94\u3001\u4f60\u53ef\u4ee5\u624b\u52a8\u91ca\u653e\u5b83\u4eec<\/strong><\/p>\n\n\n\n
      \n\n\n\n
      # \u540c\u65f6\u91ca\u653e Page Cache\u3001\u76ee\u5f55\u9879\u548c inode\nsudo sync; echo 3 > \/proc\/sys\/vm\/drop_caches<\/pre>\n\n\n\n
      \u53c2\u6570\u503c<\/td>\u542b\u4e49<\/td><\/tr><\/thead>
      1<\/td>\u91ca\u653e\u9875\u7f13\u5b58\uff08Page Cache\uff09<\/td><\/tr>
      2<\/td>\u91ca\u653e\u76ee\u5f55\u9879\u548c inode<\/td><\/tr>
      3<\/td>\u540c\u65f6\u91ca\u653e Page Cache \u548c Buffer<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
       \u3000<\/p>\n\n\n\n
      \u26a0\ufe0f\u00a0\u6ce8\u610f<\/strong>\uff1a\u8fd9\u4e0d\u662f\u4f18\u5316\u624b\u6bb5\uff0c\u4e0d\u5efa\u8bae\u9891\u7e41\u4f7f\u7528\uff0c\u4ec5\u7528\u4e8e\u8c03\u8bd5\u6216\u6d4b\u8bd5\u3002<\/p>\n\n\n\n
       \u3000<\/p>\n\n\n\n
      \ud83e\uddf0 \u516d\u3001\u600e\u4e48\u5224\u65ad Cache \u6709\u6ca1\u6709\u6548\u679c\uff1f<\/strong><\/p>\n\n\n\n
      \n\n\n\n
      \u4f7f\u7528\u00a0vfsstat<\/code>\u00a0\u6216\u00a0iostat<\/code>\u00a0\u5de5\u5177\u53ef\u4ee5\u770b\u5230\u5b9e\u9645\u547d\u4e2d\u7387\uff1a<\/p>\n\n\n\n
      # \u67e5\u770b\u78c1\u76d8\u7684\u8bfb\u5199\u60c5\u51b5\niostat -x 1\n\n# \u67e5\u770b\u6587\u4ef6\u7cfb\u7edf\u547d\u4e2d\u7387\ncat \/proc\/meminfo | grep -E 'Cached|Buffers'<\/pre>\n\n\n\n
      \u4f60\u4f1a\u53d1\u73b0\uff0c\u5176\u5b9e\u5f88\u591a\u6587\u4ef6\u7b2c\u4e8c\u6b21\u8bbf\u95ee\u65f6\u51e0\u4e4e\u4e0d\u518d\u8d70\u78c1\u76d8\uff0c\u6027\u80fd\u63d0\u5347\u5de8\u5927\u3002<\/p>\n\n\n\n
       \u3000<\/p>\n\n\n\n
      \u603b\u7ed3<\/strong><\/p>\n\n\n\n
      \n\n\n\n
      \u2705 Buffer \u662f\u201c\u5199\u78c1\u76d8\u201d\u7684\u4e2d\u8f6c\u7ad9\uff0cCache \u662f\u201c\u8bfb\u78c1\u76d8\u201d\u7684\u52a0\u901f\u5668\u3002<\/p>\n\n\n\n
      \u2705 \u770b\u4f3c\u5360\u4e86\u5f88\u591a\u5185\u5b58\uff0c\u5176\u5b9e\u662f Linux \u5229\u7528\u4e86\u201c\u95f2\u7f6e\u5185\u5b58\u201d\u6765\u52a0\u901f\u7cfb\u7edf\u6027\u80fd\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
      \u8f6c\u8f7d\uff1a\u4e00\u6587\u770b\u61c2 Linux \u7684 Buffer \u548c Cache\uff0c\u5230\u5e95\u6709\u5565\u533a\u522b\uff1f \u201c\u4e3a\u5565\u6211 free \u547d\u4ee4\u770b\u5185\u5b58\u7528 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[21],"tags":[],"_links":{"self":[{"href":"https:\/\/92it.top\/index.php?rest_route=\/wp\/v2\/posts\/18442"}],"collection":[{"href":"https:\/\/92it.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/92it.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/92it.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/92it.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=18442"}],"version-history":[{"count":4,"href":"https:\/\/92it.top\/index.php?rest_route=\/wp\/v2\/posts\/18442\/revisions"}],"predecessor-version":[{"id":18446,"href":"https:\/\/92it.top\/index.php?rest_route=\/wp\/v2\/posts\/18442\/revisions\/18446"}],"wp:attachment":[{"href":"https:\/\/92it.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=18442"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/92it.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=18442"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/92it.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=18442"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}