{"id":201259,"date":"2025-05-10T09:30:24","date_gmt":"2025-05-10T01:30:24","guid":{"rendered":"https:\/\/server.hk\/cnblog\/201259\/"},"modified":"2025-05-10T09:30:24","modified_gmt":"2025-05-10T01:30:24","slug":"%e6%b5%85%e8%b0%88%e5%86%85%e5%ad%98%e8%80%97%e5%b0%bd%e5%90%8eredis%e4%bc%9a%e5%8f%91%e7%94%9f%e4%bb%80%e4%b9%88","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/201259\/","title":{"rendered":"\u6d45\u8c08\u5185\u5b58\u8017\u5c3d\u540eRedis\u4f1a\u53d1\u751f\u4ec0\u4e48"},"content":{"rendered":"

<\/b> <\/p>\n

\u6d45\u8c08\u5185\u5b58\u8017\u5c3d\u540eRedis\u4f1a\u53d1\u751f\u4ec0\u4e48<\/h1>\n

<\/i>\u6536\u85cf<\/span> <\/p>\n

\u5728\u6570\u636e\u5e93\u5b9e\u6218\u5f00\u53d1\u7684\u8fc7\u7a0b\u4e2d\uff0c\u6211\u4eec\u7ecf\u5e38\u4f1a\u9047\u5230\u4e00\u4e9b\u8fd9\u6837\u90a3\u6837\u7684\u95ee\u9898\uff0c\u7136\u540e\u8981\u5361\u597d\u534a\u5929\uff0c\u7b49\u95ee\u9898\u89e3\u51b3\u4e86\u624d\u53d1\u73b0\u539f\u6765\u4e00\u4e9b\u7ec6\u8282\u77e5\u8bc6\u70b9\u8fd8\u662f\u6ca1\u6709\u638c\u63e1\u597d\u3002\u4eca\u5929golang\u5b66\u4e60\u7f51\u5c31\u6574\u7406\u5206\u4eab\u300a\u6d45\u8c08\u5185\u5b58\u8017\u5c3d\u540eRedis\u4f1a\u53d1\u751f\u4ec0\u4e48\u300b\uff0c\u804a\u804aRedis\u5185\u5b58\u8017\u5c3d\uff0c\u5e0c\u671b\u53ef\u4ee5\u5e2e\u52a9\u5230\u6b63\u5728\u52aa\u529b\u8d5a\u94b1\u7684\u4f60\u3002<\/p>\n

\u5185\u5b58\u56de\u6536<\/h2>\n

\u4f7f\u7528Redis<\/code> \u670d\u52a1\u65f6\uff0c\u5f88\u591a\u60c5\u51b5\u4e0b\u67d0\u4e9b\u952e\u503c\u5bf9\u53ea\u4f1a\u5728\u7279\u5b9a\u7684\u65f6\u95f4\u5185\u6709\u6548\uff0c\u4e3a\u4e86\u9632\u6b62\u8fd9\u79cd\u7c7b\u578b\u7684\u6570\u636e\u4e00\u76f4\u5360\u6709\u5185\u5b58\uff0c\u6211\u4eec\u53ef\u4ee5\u7ed9\u952e\u503c\u5bf9\u8bbe\u7f6e\u6709\u6548\u671f\u3002Redis<\/code> \u4e2d\u53ef\u4ee5\u901a\u8fc7 4<\/code> \u4e2a\u72ec\u7acb\u7684\u547d\u4ee4\u6765\u7ed9\u4e00\u4e2a\u952e\u8bbe\u7f6e\u8fc7\u671f\u65f6\u95f4\uff1a<\/p>\n

    \n
  • expire key ttl<\/code>\uff1a\u5c06 key<\/code> \u503c\u7684\u8fc7\u671f\u65f6\u95f4\u8bbe\u7f6e\u4e3a ttl<\/code> \u79d2\u3002<\/li>\n
  • pexpire key ttl<\/code>\uff1a\u5c06 key<\/code> \u503c\u7684\u8fc7\u671f\u65f6\u95f4\u8bbe\u7f6e\u4e3a ttl<\/code> \u6beb\u79d2\u3002<\/li>\n
  • expireat key timestamp<\/code>\uff1a\u5c06 key<\/code> \u503c\u7684\u8fc7\u671f\u65f6\u95f4\u8bbe\u7f6e\u4e3a\u6307\u5b9a\u7684 timestamp<\/code> \u79d2\u6570\u3002<\/li>\n
  • pexpireat key timestamp<\/code>\uff1a\u5c06 key<\/code> \u503c\u7684\u8fc7\u671f\u65f6\u95f4\u8bbe\u7f6e\u4e3a\u6307\u5b9a\u7684 timestamp<\/code> \u6beb\u79d2\u6570\u3002<\/li>\n<\/ul>\n

    PS\uff1a\u4e0d\u7ba1\u4f7f\u7528\u54ea\u4e00\u4e2a\u547d\u4ee4\uff0c\u6700\u7ec8 Redis<\/code> \u5e95\u5c42\u90fd\u662f\u4f7f\u7528 pexpireat<\/code> \u547d\u4ee4\u6765\u5b9e\u73b0\u7684\u3002\u53e6\u5916\uff0cset<\/code> \u7b49\u547d\u4ee4\u4e5f\u53ef\u4ee5\u8bbe\u7f6e key<\/code> \u7684\u540c\u65f6\u52a0\u4e0a\u8fc7\u671f\u65f6\u95f4\uff0c\u8fd9\u6837\u53ef\u4ee5\u4fdd\u8bc1\u8bbe\u503c\u548c\u8bbe\u8fc7\u671f\u65f6\u95f4\u7684\u539f\u5b50\u6027\u3002<\/p>\n

    \u8bbe\u7f6e\u4e86\u6709\u6548\u671f\u540e\uff0c\u53ef\u4ee5\u901a\u8fc7 ttl<\/code> \u548c pttl<\/code> \u4e24\u4e2a\u547d\u4ee4\u6765\u67e5\u8be2\u5269\u4f59\u8fc7\u671f\u65f6\u95f4\uff08\u5982\u679c\u672a\u8bbe\u7f6e\u8fc7\u671f\u65f6\u95f4\u5219\u4e0b\u9762\u4e24\u4e2a\u547d\u4ee4\u8fd4\u56de -1<\/code>\uff0c\u5982\u679c\u8bbe\u7f6e\u4e86\u4e00\u4e2a\u975e\u6cd5\u7684\u8fc7\u671f\u65f6\u95f4\uff0c\u5219\u90fd\u8fd4\u56de -2<\/code>\uff09\uff1a<\/p>\n

      \n
    • ttl key<\/code> \u8fd4\u56de key<\/code> \u5269\u4f59\u8fc7\u671f\u79d2\u6570\u3002<\/li>\n
    • pttl key<\/code> \u8fd4\u56de key<\/code> \u5269\u4f59\u8fc7\u671f\u7684\u6beb\u79d2\u6570\u3002<\/li>\n<\/ul>\n

      \u8fc7\u671f\u7b56\u7565<\/h2>\n

      \u5982\u679c\u5c06\u4e00\u4e2a\u8fc7\u671f\u7684\u952e\u5220\u9664\uff0c\u6211\u4eec\u4e00\u822c\u90fd\u4f1a\u6709\u4e09\u79cd\u7b56\u7565\uff1a<\/p>\n

        \n
      • \u5b9a\u65f6\u5220\u9664\uff1a\u4e3a\u6bcf\u4e2a\u952e\u8bbe\u7f6e\u4e00\u4e2a\u5b9a\u65f6\u5668\uff0c\u4e00\u65e6\u8fc7\u671f\u65f6\u95f4\u5230\u4e86\uff0c\u5219\u5c06\u952e\u5220\u9664\u3002\u8fd9\u79cd\u7b56\u7565\u5bf9\u5185\u5b58\u5f88\u53cb\u597d\uff0c\u4f46\u662f\u5bf9 CPU<\/code> \u4e0d\u53cb\u597d\uff0c\u56e0\u4e3a\u6bcf\u4e2a\u5b9a\u65f6\u5668\u90fd\u4f1a\u5360\u7528\u4e00\u5b9a\u7684 CPU<\/code> \u8d44\u6e90\u3002<\/li>\n
      • \u60f0\u6027\u5220\u9664\uff1a\u4e0d\u7ba1\u952e\u6709\u6ca1\u6709\u8fc7\u671f\u90fd\u4e0d\u4e3b\u52a8\u5220\u9664\uff0c\u7b49\u5230\u6bcf\u6b21\u53bb\u83b7\u53d6\u952e\u65f6\u518d\u5224\u65ad\u662f\u5426\u8fc7\u671f\uff0c\u5982\u679c\u8fc7\u671f\u5c31\u5220\u9664\u8be5\u952e\uff0c\u5426\u5219\u8fd4\u56de\u952e\u5bf9\u5e94\u7684\u503c\u3002\u8fd9\u79cd\u7b56\u7565\u5bf9\u5185\u5b58\u4e0d\u591f\u53cb\u597d\uff0c\u53ef\u80fd\u4f1a\u6d6a\u8d39\u5f88\u591a\u5185\u5b58\u3002<\/li>\n
      • \u5b9a\u671f\u626b\u63cf\uff1a\u7cfb\u7edf\u6bcf\u9694\u4e00\u6bb5\u65f6\u95f4\u5c31\u5b9a\u671f\u626b\u63cf\u4e00\u6b21\uff0c\u53d1\u73b0\u8fc7\u671f\u7684\u952e\u5c31\u8fdb\u884c\u5220\u9664\u3002\u8fd9\u79cd\u7b56\u7565\u76f8\u5bf9\u6765\u8bf4\u662f\u4e0a\u9762\u4e24\u79cd\u7b56\u7565\u7684\u6298\u4e2d\u65b9\u6848\uff0c\u9700\u8981\u6ce8\u610f\u7684\u662f\u8fd9\u4e2a\u5b9a\u671f\u7684\u9891\u7387\u8981\u7ed3\u5408\u5b9e\u9645\u60c5\u51b5\u638c\u63a7\u597d\uff0c\u4f7f\u7528\u8fd9\u79cd\u65b9\u6848\u6709\u4e00\u4e2a\u7f3a\u9677\u5c31\u662f\u53ef\u80fd\u4f1a\u51fa\u73b0\u5df2\u7ecf\u8fc7\u671f\u7684\u952e\u4e5f\u88ab\u8fd4\u56de\u3002<\/li>\n<\/ul>\n

        \u5728 Redis<\/code> \u5f53\u4e2d\uff0c\u5176\u9009\u62e9\u7684\u662f\u7b56\u7565 2<\/code> \u548c\u7b56\u7565 3<\/code> \u7684\u7efc\u5408\u4f7f\u7528\u3002\u4e0d\u8fc7 Redis<\/code> \u7684\u5b9a\u671f\u626b\u63cf\u53ea\u4f1a\u626b\u63cf\u8bbe\u7f6e\u4e86\u8fc7\u671f\u65f6\u95f4\u7684\u952e\uff0c\u56e0\u4e3a\u8bbe\u7f6e\u4e86\u8fc7\u671f\u65f6\u95f4\u7684\u952e Redis<\/code> \u4f1a\u5355\u72ec\u5b58\u50a8\uff0c\u6240\u4ee5\u4e0d\u4f1a\u51fa\u73b0\u626b\u63cf\u6240\u6709\u952e\u7684\u60c5\u51b5\uff1a<\/p>\n

        \ntypedef struct redisDb {\n  dict *dict; \/\/\u6240\u6709\u7684\u952e\u503c\u5bf9\n  dict *expires; \/\/\u8bbe\u7f6e\u4e86\u8fc7\u671f\u65f6\u95f4\u7684\u952e\u503c\u5bf9\n  dict *blocking_keys; \/\/\u88ab\u963b\u585e\u7684key,\u5982\u5ba2\u6237\u7aef\u6267\u884cBLPOP\u7b49\u963b\u585e\u6307\u4ee4\u65f6\n  dict *watched_keys; \/\/WATCHED keys\n  int id; \/\/Database ID\n  \/\/... \u7701\u7565\u4e86\u5176\u4ed6\u5c5e\u6027\n} redisDb;<\/pre>\n
        8 \u79cd\u6dd8\u6c70\u7b56\u7565<\/h2>\n
        \u5047\u5982 Redis<\/code> \u5f53\u4e2d\u6240\u6709\u7684\u952e\u90fd\u6ca1\u6709\u8fc7\u671f\uff0c\u800c\u4e14\u6b64\u65f6\u5185\u5b58\u6ee1\u4e86\uff0c\u90a3\u4e48\u5ba2\u6237\u7aef\u7ee7\u7eed\u6267\u884c set<\/code> \u7b49\u547d\u4ee4\u65f6 Redis<\/code> \u4f1a\u600e\u4e48\u5904\u7406\u5462\uff1fRedis<\/code> \u5f53\u4e2d\u63d0\u4f9b\u4e86\u4e0d\u540c\u7684\u6dd8\u6c70\u7b56\u7565\u6765\u5904\u7406\u8fd9\u79cd\u573a\u666f\u3002<\/p>\n
        \u9996\u5148 Redis<\/code> \u63d0\u4f9b\u4e86\u4e00\u4e2a\u53c2\u6570 maxmemory<\/code> \u6765\u914d\u7f6e Redis<\/code> \u6700\u5927\u4f7f\u7528\u5185\u5b58\uff1a<\/p>\n
        \nmaxmemory \n   <\/pre>\n
        \u6216\u8005\u4e5f\u53ef\u4ee5\u901a\u8fc7\u547d\u4ee4 config set maxmemory 1GB<\/code> \u6765\u52a8\u6001\u4fee\u6539\u3002<\/p>\n
        \u5982\u679c\u6ca1\u6709\u8bbe\u7f6e\u8be5\u53c2\u6570\uff0c\u90a3\u4e48\u5728 32<\/code> \u4f4d\u7684\u64cd\u4f5c\u7cfb\u7edf\u4e2d Redis<\/code> \u6700\u591a\u4f7f\u7528 3GB<\/code> \u5185\u5b58\uff0c\u800c\u5728 64<\/code> \u4f4d\u7684\u64cd\u4f5c\u7cfb\u7edf\u4e2d\u5219\u4e0d\u4f5c\u9650\u5236\u3002<\/p>\n
        Redis<\/code> \u4e2d\u63d0\u4f9b\u4e86 8<\/code> \u79cd\u6dd8\u6c70\u7b56\u7565\uff0c\u53ef\u4ee5\u901a\u8fc7\u53c2\u6570 maxmemory-policy<\/code> \u8fdb\u884c\u914d\u7f6e\uff1a<\/p>\n<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n
        \u6dd8\u6c70\u7b56\u7565<\/th>\n\u8bf4\u660e<\/th>\n<\/tr>\n<\/thead>\n
        volatile-lru<\/td>\n\u6839\u636e LRU \u7b97\u6cd5\u5220\u9664\u8bbe\u7f6e\u4e86\u8fc7\u671f\u65f6\u95f4\u7684\u952e\uff0c\u76f4\u5230\u817e\u51fa\u53ef\u7528\u7a7a\u95f4\u3002\u5982\u679c\u6ca1\u6709\u53ef\u5220\u9664\u7684\u952e\u5bf9\u8c61\uff0c\u4e14\u5185\u5b58\u8fd8\u662f\u4e0d\u591f\u7528\u65f6\uff0c\u5219\u62a5\u9519<\/td>\n<\/tr>\n
        allkeys-lru<\/td>\n\u6839\u636e LRU \u7b97\u6cd5\u5220\u9664\u6240\u6709\u7684\u952e\uff0c\u76f4\u5230\u817e\u51fa\u53ef\u7528\u7a7a\u95f4\u3002\u5982\u679c\u6ca1\u6709\u53ef\u5220\u9664\u7684\u952e\u5bf9\u8c61\uff0c\u4e14\u5185\u5b58\u8fd8\u662f\u4e0d\u591f\u7528\u65f6\uff0c\u5219\u62a5\u9519<\/td>\n<\/tr>\n
        volatile-lfu<\/td>\n\u6839\u636e LFU \u7b97\u6cd5\u5220\u9664\u8bbe\u7f6e\u4e86\u8fc7\u671f\u65f6\u95f4\u7684\u952e\uff0c\u76f4\u5230\u817e\u51fa\u53ef\u7528\u7a7a\u95f4\u3002\u5982\u679c\u6ca1\u6709\u53ef\u5220\u9664\u7684\u952e\u5bf9\u8c61\uff0c\u4e14\u5185\u5b58\u8fd8\u662f\u4e0d\u591f\u7528\u65f6\uff0c\u5219\u62a5\u9519<\/td>\n<\/tr>\n
        allkeys-lfu<\/td>\n\u6839\u636e LFU \u7b97\u6cd5\u5220\u9664\u6240\u6709\u7684\u952e\uff0c\u76f4\u5230\u817e\u51fa\u53ef\u7528\u7a7a\u95f4\u3002\u5982\u679c\u6ca1\u6709\u53ef\u5220\u9664\u7684\u952e\u5bf9\u8c61\uff0c\u4e14\u5185\u5b58\u8fd8\u662f\u4e0d\u591f\u7528\u65f6\uff0c\u5219\u62a5\u9519<\/td>\n<\/tr>\n
        volatile-random<\/td>\n\u968f\u673a\u5220\u9664\u8bbe\u7f6e\u4e86\u8fc7\u671f\u65f6\u95f4\u7684\u952e\uff0c\u76f4\u5230\u817e\u51fa\u53ef\u7528\u7a7a\u95f4\u3002\u5982\u679c\u6ca1\u6709\u53ef\u5220\u9664\u7684\u952e\u5bf9\u8c61\uff0c\u4e14\u5185\u5b58\u8fd8\u662f\u4e0d\u591f\u7528\u65f6\uff0c\u5219\u62a5\u9519<\/td>\n<\/tr>\n
        allkeys-random<\/td>\n\u968f\u673a\u5220\u9664\u6240\u6709\u952e\uff0c\u76f4\u5230\u817e\u51fa\u53ef\u7528\u7a7a\u95f4\u3002\u5982\u679c\u6ca1\u6709\u53ef\u5220\u9664\u7684\u952e\u5bf9\u8c61\uff0c\u4e14\u5185\u5b58\u8fd8\u662f\u4e0d\u591f\u7528\u65f6\uff0c\u5219\u62a5\u9519<\/td>\n<\/tr>\n
        volatile-ttl<\/td>\n\u6839\u636e\u952e\u503c\u5bf9\u8c61\u7684 ttl \u5c5e\u6027\uff0c \u5220\u9664\u6700\u8fd1\u5c06\u8981\u8fc7\u671f\u6570\u636e\u3002 \u5982\u679c\u6ca1\u6709\uff0c\u5219\u76f4\u63a5\u62a5\u9519<\/td>\n<\/tr>\n
        noeviction<\/td>\n\u9ed8\u8ba4\u7b56\u7565\uff0c\u4e0d\u4f5c\u4efb\u4f55\u5904\u7406\uff0c\u76f4\u63a5\u62a5\u9519<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
        PS\uff1a\u6dd8\u6c70\u7b56\u7565\u4e5f\u53ef\u4ee5\u76f4\u63a5\u4f7f\u7528\u547d\u4ee4 config set maxmemory-policy <\/code> \u6765\u8fdb\u884c\u52a8\u6001\u914d\u7f6e\u3002<\/p>\n
        LRU \u7b97\u6cd5<\/h2>\n
        LRU<\/code> \u5168\u79f0\u4e3a\uff1aLeast Recently Used<\/code>\u3002\u5373\uff1a\u6700\u8fd1\u6700\u957f\u65f6\u95f4\u672a\u88ab\u4f7f\u7528\u3002\u8fd9\u4e2a\u4e3b\u8981\u9488\u5bf9\u7684\u662f\u4f7f\u7528\u65f6\u95f4\u3002<\/p>\n
        Redis \u6539\u8fdb\u540e\u7684 LRU \u7b97\u6cd5<\/strong><\/p>\n
        \u5728 Redis<\/code> \u5f53\u4e2d\uff0c\u5e76\u6ca1\u6709\u91c7\u7528\u4f20\u7edf\u7684 LRU<\/code> \u7b97\u6cd5\uff0c\u56e0\u4e3a\u4f20\u7edf\u7684 LRU<\/code> \u7b97\u6cd5\u5b58\u5728 2<\/code> \u4e2a\u95ee\u9898\uff1a<\/p>\n
          \n
        • \u9700\u8981\u989d\u5916\u7684\u7a7a\u95f4\u8fdb\u884c\u5b58\u50a8\u3002<\/li>\n
        • \u53ef\u80fd\u5b58\u5728\u67d0\u4e9b key<\/code> \u503c\u4f7f\u7528\u5f88\u9891\u7e41\uff0c\u4f46\u662f\u6700\u8fd1\u6ca1\u88ab\u4f7f\u7528\uff0c\u4ece\u800c\u88ab LRU<\/code> \u7b97\u6cd5\u5220\u9664\u3002<\/li>\n<\/ul>\n
          \u4e3a\u4e86\u907f\u514d\u4ee5\u4e0a 2<\/code> \u4e2a\u95ee\u9898\uff0cRedis<\/code> \u5f53\u4e2d\u5bf9\u4f20\u7edf\u7684 LRU<\/code> \u7b97\u6cd5\u8fdb\u884c\u4e86\u6539\u9020\uff0c\u901a\u8fc7\u62bd\u6837\u7684\u65b9\u5f0f\u8fdb\u884c\u5220\u9664\u3002<\/p>\n
          \u914d\u7f6e\u6587\u4ef6\u4e2d\u63d0\u4f9b\u4e86\u4e00\u4e2a\u5c5e\u6027 maxmemory_samples 5<\/code>\uff0c\u9ed8\u8ba4\u503c\u5c31\u662f 5<\/code>\uff0c\u8868\u793a\u968f\u673a\u62bd\u53d6 5<\/code> \u4e2a key<\/code> \u503c\uff0c\u7136\u540e\u5bf9\u8fd9 5<\/code> \u4e2a key<\/code> \u503c\u6309\u7167 LRU<\/code> \u7b97\u6cd5\u8fdb\u884c\u5220\u9664\uff0c\u6240\u4ee5\u5f88\u660e\u663e\uff0ckey<\/code> \u503c\u8d8a\u5927\uff0c\u5220\u9664\u7684\u51c6\u786e\u5ea6\u8d8a\u9ad8\u3002<\/p>\n
          \u5bf9\u62bd\u6837 LRU<\/code> \u7b97\u6cd5\u548c\u4f20\u7edf\u7684 LRU<\/code> \u7b97\u6cd5\uff0cRedis<\/code> \u5b98\u7f51\u5f53\u4e2d\u6709\u4e00\u4e2a\u5bf9\u6bd4\u56fe\uff1a<\/p>\n
            \n
          • \u6d45\u7070\u8272\u5e26\u662f\u88ab\u5220\u9664\u7684\u5bf9\u8c61\u3002<\/li>\n
          • \u7070\u8272\u5e26\u662f\u672a\u88ab\u5220\u9664\u7684\u5bf9\u8c61\u3002<\/li>\n
          • \u7eff\u8272\u662f\u6dfb\u52a0\u7684\u5bf9\u8c61\u3002<\/li>\n<\/ul>\n
            <\/p>\n
            \u5de6\u4e0a\u89d2\u7b2c\u4e00\u5e45\u56fe\u4ee3\u8868\u7684\u662f\u4f20\u7edf LRU<\/code> \u7b97\u6cd5\uff0c\u53ef\u4ee5\u770b\u5230\uff0c\u5f53\u62bd\u6837\u6570\u8fbe\u5230 10<\/code> \u4e2a\uff08\u53f3\u4e0a\u89d2\uff09\uff0c\u5df2\u7ecf\u548c\u4f20\u7edf\u7684 LRU<\/code> \u7b97\u6cd5\u975e\u5e38\u63a5\u8fd1\u4e86\u3002<\/p>\n
            Redis \u5982\u4f55\u7ba1\u7406\u70ed\u5ea6\u6570\u636e<\/strong><\/p>\n
            \u524d\u9762\u6211\u4eec\u8bb2\u8ff0\u5b57\u7b26\u4e32\u5bf9\u8c61\u65f6\uff0c\u63d0\u5230\u4e86 redisObject<\/code> \u5bf9\u8c61\u4e2d\u5b58\u5728\u4e00\u4e2a lru<\/code> \u5c5e\u6027\uff1a<\/p>\n
            \ntypedef struct redisObject {\n  unsigned type:4;\/\/\u5bf9\u8c61\u7c7b\u578b\uff084\u4f4d=0.5\u5b57\u8282\uff09\n  unsigned encoding:4;\/\/\u7f16\u7801\uff084\u4f4d=0.5\u5b57\u8282\uff09\n  unsigned lru:LRU_BITS;\/\/\u8bb0\u5f55\u5bf9\u8c61\u6700\u540e\u4e00\u6b21\u88ab\u5e94\u7528\u7a0b\u5e8f\u8bbf\u95ee\u7684\u65f6\u95f4\uff0824\u4f4d=3\u5b57\u8282\uff09\n  int refcount;\/\/\u5f15\u7528\u8ba1\u6570\u3002\u7b49\u4e8e0\u65f6\u8868\u793a\u53ef\u4ee5\u88ab\u5783\u573e\u56de\u6536\uff0832\u4f4d=4\u5b57\u8282\uff09\n  void *ptr;\/\/\u6307\u5411\u5e95\u5c42\u5b9e\u9645\u7684\u6570\u636e\u5b58\u50a8\u7ed3\u6784\uff0c\u5982\uff1aSDS\u7b49(8\u5b57\u8282)\n} robj;<\/pre>\n
            lru<\/code> \u5c5e\u6027\u662f\u521b\u5efa\u5bf9\u8c61\u7684\u65f6\u5019\u5199\u5165\uff0c\u5bf9\u8c61\u88ab\u8bbf\u95ee\u5230\u65f6\u4e5f\u4f1a\u8fdb\u884c\u66f4\u65b0\u3002\u6b63\u5e38\u4eba\u7684\u601d\u8def\u5c31\u662f\u6700\u540e\u51b3\u5b9a\u8981\u4e0d\u8981\u5220\u9664\u67d0\u4e00\u4e2a\u952e\u80af\u5b9a\u662f\u7528\u5f53\u524d\u65f6\u95f4\u6233\u51cf\u53bb lru<\/code>\uff0c\u5dee\u503c\u6700\u5927\u7684\u5c31\u4f18\u5148\u88ab\u5220\u9664\u3002\u4f46\u662f Redis<\/code> \u91cc\u9762\u5e76\u4e0d\u662f\u8fd9\u4e48\u505a\u7684\uff0cRedis<\/code> \u4e2d\u7ef4\u62a4\u4e86\u4e00\u4e2a\u5168\u5c40\u5c5e\u6027 lru_clock<\/code>\uff0c\u8fd9\u4e2a\u5c5e\u6027\u662f\u901a\u8fc7\u4e00\u4e2a\u5168\u5c40\u51fd\u6570 serverCron<\/code> \u6bcf\u9694 100<\/code> \u6beb\u79d2\u6267\u884c\u4e00\u6b21\u6765\u66f4\u65b0\u7684\uff0c\u8bb0\u5f55\u7684\u662f\u5f53\u524d unix<\/code> \u65f6\u95f4\u6233\u3002<\/p>\n
            \u6700\u540e\u51b3\u5b9a\u5220\u9664\u7684\u6570\u636e\u662f\u901a\u8fc7 lru_clock<\/code> \u51cf\u53bb\u5bf9\u8c61\u7684 lru<\/code> \u5c5e\u6027\u800c\u5f97\u51fa\u7684\u3002\u90a3\u4e48\u4e3a\u4ec0\u4e48 Redis<\/code> \u8981\u8fd9\u4e48\u505a\u5462\uff1f\u76f4\u63a5\u53d6\u5168\u5c40\u65f6\u95f4\u4e0d\u662f\u66f4\u51c6\u786e\u5417\uff1f<\/p>\n
            \u8fd9\u662f\u56e0\u4e3a\u8fd9\u4e48\u505a\u53ef\u4ee5\u907f\u514d\u6bcf\u6b21\u66f4\u65b0\u5bf9\u8c61\u7684 lru<\/code> \u5c5e\u6027\u7684\u65f6\u5019\u53ef\u4ee5\u76f4\u63a5\u53d6\u5168\u5c40\u5c5e\u6027\uff0c\u800c\u4e0d\u9700\u8981\u53bb\u8c03\u7528\u7cfb\u7edf\u51fd\u6570\u6765\u83b7\u53d6\u7cfb\u7edf\u65f6\u95f4\uff0c\u4ece\u800c\u63d0\u5347\u6548\u7387\uff08Redis<\/code> \u5f53\u4e2d\u6709\u5f88\u591a\u8fd9\u79cd\u7ec6\u8282\u8003\u8651\u6765\u63d0\u5347\u6027\u80fd\uff0c\u53ef\u4ee5\u8bf4\u662f\u5bf9\u6027\u80fd\u5c3d\u53ef\u80fd\u7684\u4f18\u5316\u5230\u6781\u81f4\uff09\u3002<\/p>\n
            \u4e0d\u8fc7\u8fd9\u91cc\u8fd8\u6709\u4e00\u4e2a\u95ee\u9898\uff0c\u6211\u4eec\u770b\u5230\uff0credisObject<\/code> \u5bf9\u8c61\u4e2d\u7684 lru<\/code> \u5c5e\u6027\u53ea\u6709 24<\/code> \u4f4d\uff0c24<\/code> \u4f4d\u53ea\u80fd\u5b58\u50a8 194<\/code> \u5929\u7684\u65f6\u95f4\u6233\u5927\u5c0f\uff0c\u4e00\u65e6\u8d85\u8fc7 194<\/code> \u5929\u4e4b\u540e\u5c31\u4f1a\u91cd\u65b0\u4ece 0<\/code> \u5f00\u59cb\u8ba1\u7b97\uff0c\u6240\u4ee5\u8fd9\u65f6\u5019\u5c31\u53ef\u80fd\u4f1a\u51fa\u73b0 redisObject<\/code> \u5bf9\u8c61\u4e2d\u7684 lru<\/code> \u5c5e\u6027\u5927\u4e8e\u5168\u5c40\u7684 lru_clock<\/code> \u5c5e\u6027\u7684\u60c5\u51b5\u3002<\/p>\n
            \u6b63\u56e0\u4e3a\u5982\u6b64\uff0c\u6240\u4ee5\u8ba1\u7b97\u7684\u65f6\u5019\u4e5f\u9700\u8981\u5206\u4e3a 2<\/code> \u79cd\u60c5\u51b5\uff1a<\/p>\n
              \n
            • \u5f53\u5168\u5c40 lruclock<\/code> > lru<\/code>\uff0c\u5219\u4f7f\u7528 lruclock<\/code> – lru<\/code> \u5f97\u5230\u7a7a\u95f2\u65f6\u95f4\u3002<\/li>\n
            • \u5f53\u5168\u5c40 lruclock<\/code> lru\uff0c\u5219\u4f7f\u7528 lruclock_max<\/code>\uff08\u5373 194<\/code> \u5929\uff09 – lru<\/code> + lruclock<\/code> \u5f97\u5230\u7a7a\u95f2\u65f6\u95f4\u3002<\/li>\n<\/ul>\n
              \u9700\u8981\u6ce8\u610f\u7684\u662f\uff0c\u8fd9\u79cd\u8ba1\u7b97\u65b9\u5f0f\u5e76\u4e0d\u80fd\u4fdd\u8bc1\u62bd\u6837\u7684\u6570\u636e\u4e2d\u4e00\u5b9a\u80fd\u5220\u9664\u7a7a\u95f2\u65f6\u95f4\u6700\u957f\u7684\u3002\u8fd9\u662f\u56e0\u4e3a\u9996\u5148\u8d85\u8fc7 194<\/code> \u5929\u8fd8\u4e0d\u88ab\u4f7f\u7528\u7684\u60c5\u51b5\u5f88\u5c11\uff0c\u518d\u6b21\u53ea\u6709 lruclock<\/code> \u7b2c 2<\/code> \u8f6e\u7ee7\u7eed\u8d85\u8fc7 lru<\/code> \u5c5e\u6027\u65f6\uff0c\u8ba1\u7b97\u624d\u4f1a\u51fa\u95ee\u9898\u3002<\/p>\n
              \u6bd4\u5982\u5bf9\u8c61 A<\/code> \u8bb0\u5f55\u7684 lru<\/code> \u662f 1<\/code> \u5929\uff0c\u800c lruclock<\/code> \u7b2c\u4e8c\u8f6e\u90fd\u5230 10<\/code> \u5929\u4e86\uff0c\u8fd9\u65f6\u5019\u5c31\u4f1a\u5bfc\u81f4\u8ba1\u7b97\u7ed3\u679c\u53ea\u6709 10-1=9<\/code> \u5929\uff0c\u5b9e\u9645\u4e0a\u5e94\u8be5\u662f 194+10-1=203<\/code> \u5929\u3002\u4f46\u662f\u8fd9\u79cd\u60c5\u51b5\u53ef\u4ee5\u8bf4\u53c8\u662f\u66f4\u5c11\u53d1\u751f\uff0c\u6240\u4ee5\u8bf4\u8fd9\u79cd\u5904\u7406\u65b9\u5f0f\u662f\u53ef\u80fd\u5b58\u5728\u5220\u9664\u4e0d\u51c6\u786e\u7684\u60c5\u51b5\uff0c\u4f46\u662f\u672c\u8eab\u8fd9\u79cd\u7b97\u6cd5\u5c31\u662f\u4e00\u79cd\u8fd1\u4f3c\u7684\u7b97\u6cd5\uff0c\u6240\u4ee5\u5e76\u4e0d\u4f1a\u6709\u592a\u5927\u5f71\u54cd\u3002<\/p>\n
              LFU \u7b97\u6cd5<\/h2>\n
              LFU<\/code> \u5168\u79f0\u4e3a\uff1aLeast Frequently Used<\/code>\u3002\u5373\uff1a\u6700\u8fd1\u6700\u5c11\u9891\u7387\u4f7f\u7528\uff0c\u8fd9\u4e2a\u4e3b\u8981\u9488\u5bf9\u7684\u662f\u4f7f\u7528\u9891\u7387\u3002\u8fd9\u4e2a\u5c5e\u6027\u4e5f\u662f\u8bb0\u5f55\u5728redisObject<\/code> \u4e2d\u7684 lru<\/code> \u5c5e\u6027\u5185\u3002<\/p>\n
              \u5f53\u6211\u4eec\u91c7\u7528 LFU<\/code> \u56de\u6536\u7b56\u7565\u65f6\uff0clru<\/code> \u5c5e\u6027\u7684\u9ad8 16<\/code> \u4f4d\u7528\u6765\u8bb0\u5f55\u8bbf\u95ee\u65f6\u95f4\uff08last decrement time\uff1aldt\uff0c\u5355\u4f4d\u4e3a\u5206\u949f\uff09\uff0c\u4f4e 8<\/code> \u4f4d\u7528\u6765\u8bb0\u5f55\u8bbf\u95ee\u9891\u7387\uff08logistic counter\uff1alogc\uff09\uff0c\u7b80\u79f0 counter<\/code>\u3002<\/p>\n
              \u8bbf\u95ee\u9891\u6b21\u9012\u589e<\/strong><\/p>\n
              LFU<\/code> \u8ba1\u6570\u5668\u6bcf\u4e2a\u952e\u53ea\u6709 8<\/code> \u4f4d\uff0c\u5b83\u80fd\u8868\u793a\u7684\u6700\u5927\u503c\u662f 255<\/code>\uff0c\u6240\u4ee5 Redis<\/code> \u4f7f\u7528\u7684\u662f\u4e00\u79cd\u57fa\u4e8e\u6982\u7387\u7684\u5bf9\u6570\u5668\u6765\u5b9e\u73b0 counter<\/code> \u7684\u9012\u589e\u3002r<\/p>\n
              \u7ed9\u5b9a\u4e00\u4e2a\u65e7\u7684\u8bbf\u95ee\u9891\u6b21\uff0c\u5f53\u4e00\u4e2a\u952e\u88ab\u8bbf\u95ee\u65f6\uff0ccounter<\/code> \u6309\u4ee5\u4e0b\u65b9\u5f0f\u9012\u589e\uff1a<\/p>\n
                \n
              • \u63d0\u53d6 0<\/code> \u548c 1<\/code> \u4e4b\u95f4\u7684\u968f\u673a\u6570 R<\/code>\u3002<\/li>\n
              • counter<\/code> – \u521d\u59cb\u503c\uff08\u9ed8\u8ba4\u4e3a 5<\/code>\uff09\uff0c\u5f97\u5230\u4e00\u4e2a\u57fa\u7840\u5dee\u503c\uff0c\u5982\u679c\u8fd9\u4e2a\u5dee\u503c\u5c0f\u4e8e 0<\/code>\uff0c\u5219\u76f4\u63a5\u53d6 0<\/code>\uff0c\u4e3a\u4e86\u65b9\u4fbf\u8ba1\u7b97\uff0c\u628a\u8fd9\u4e2a\u5dee\u503c\u8bb0\u4e3a baseval<\/code>\u3002<\/li>\n
              • \u6982\u7387 P<\/code> \u8ba1\u7b97\u516c\u5f0f\u4e3a\uff1a1\/(baseval * lfu_log_factor + 1)<\/code>\u3002<\/li>\n
              • \u5982\u679c R \u65f6\uff0c\u9891\u6b21\u8fdb\u884c\u9012\u589e\uff08counter++<\/code>\uff09\u3002<\/code><\/li>\n<\/ul>\n
                \u516c\u5f0f\u4e2d\u7684 lfu_log_factor<\/code> \u79f0\u4e4b\u4e3a\u5bf9\u6570\u56e0\u5b50\uff0c\u9ed8\u8ba4\u662f 10<\/code> \uff0c\u53ef\u4ee5\u901a\u8fc7\u53c2\u6570\u6765\u8fdb\u884c\u63a7\u5236\uff1a<\/p>\n
                \nlfu_log_factor 10<\/pre>\n
                \u4e0b\u56fe\u5c31\u662f\u5bf9\u6570\u56e0\u5b50 lfu_log_factor<\/code> \u548c\u9891\u6b21 counter<\/code> \u589e\u957f\u7684\u5173\u7cfb\u56fe\uff1a<\/p>\n
                <\/p>\n
                \u53ef\u4ee5\u770b\u5230\uff0c\u5f53\u5bf9\u6570\u56e0\u5b50 lfu_log_factor<\/code> \u4e3a 100<\/code> \u65f6\uff0c\u5927\u6982\u662f 10M\uff081000\u4e07\uff09<\/code> \u6b21\u8bbf\u95ee\u624d\u4f1a\u5c06\u8bbf\u95ee counter<\/code> \u589e\u957f\u5230 255<\/code>\uff0c\u800c\u9ed8\u8ba4\u7684 10<\/code> \u4e5f\u80fd\u652f\u6301\u5230 1M\uff08100\u4e07\uff09<\/code> \u6b21\u8bbf\u95ee counter<\/code> \u624d\u80fd\u8fbe\u5230 255<\/code> \u4e0a\u9650\uff0c\u8fd9\u5728\u5927\u90e8\u5206\u573a\u666f\u90fd\u662f\u8db3\u591f\u6ee1\u8db3\u9700\u6c42\u7684\u3002<\/p>\n
                \u8bbf\u95ee\u9891\u6b21\u9012\u51cf<\/h2>\n
                \u5982\u679c\u8bbf\u95ee\u9891\u6b21 counter<\/code> \u53ea\u662f\u4e00\u76f4\u5728\u9012\u589e\uff0c\u90a3\u4e48\u8fdf\u65e9\u4f1a\u5168\u90e8\u90fd\u5230 255<\/code>\uff0c\u4e5f\u5c31\u662f\u8bf4 counter<\/code> \u4e00\u76f4\u9012\u589e\u4e0d\u80fd\u5b8c\u5168\u53cd\u5e94\u4e00\u4e2a key<\/code> \u7684\u70ed\u5ea6\u7684\uff0c\u6240\u4ee5\u5f53\u67d0\u4e00\u4e2a key<\/code> \u4e00\u6bb5\u65f6\u95f4\u4e0d\u88ab\u8bbf\u95ee\u4e4b\u540e\uff0ccounter<\/code> \u4e5f\u9700\u8981\u5bf9\u5e94\u51cf\u5c11\u3002<\/p>\n
                counter<\/code> \u7684\u51cf\u5c11\u901f\u5ea6\u7531\u53c2\u6570 lfu-decay-time<\/code> \u8fdb\u884c\u63a7\u5236\uff0c\u9ed8\u8ba4\u662f 1<\/code>\uff0c\u5355\u4f4d\u662f\u5206\u949f\u3002\u9ed8\u8ba4\u503c 1<\/code> \u8868\u793a\uff1aN<\/code> \u5206\u949f\u5185\u6ca1\u6709\u8bbf\u95ee\uff0ccounter<\/code> \u5c31\u8981\u51cf N<\/code>\u3002<\/p>\n
                \nlfu-decay-time 1<\/pre>\n
                \u5177\u4f53\u7b97\u6cd5\u5982\u4e0b\uff1a<\/p>\n
                  \n
                • \u83b7\u53d6\u5f53\u524d\u65f6\u95f4\u6233\uff0c\u8f6c\u5316\u4e3a\u5206\u949f\u540e\u53d6\u4f4e 16<\/code> \u4f4d\uff08\u4e3a\u4e86\u65b9\u4fbf\u540e\u7eed\u8ba1\u7b97\uff0c\u8fd9\u4e2a\u503c\u8bb0\u4e3a now<\/code>\uff09\u3002<\/li>\n
                • \u53d6\u51fa\u5bf9\u8c61\u5185\u7684 lru<\/code> \u5c5e\u6027\u4e2d\u7684\u9ad8 16<\/code> \u4f4d\uff08\u4e3a\u4e86\u65b9\u4fbf\u540e\u7eed\u8ba1\u7b97\uff0c\u8fd9\u4e2a\u503c\u8bb0\u4e3a ldt<\/code>\uff09\u3002<\/li>\n
                • \u5f53 lru<\/code> > now<\/code> \u65f6\uff0c\u9ed8\u8ba4\u4e3a\u8fc7\u4e86\u4e00\u4e2a\u5468\u671f\uff0816<\/code> \u4f4d\uff0c\u6700\u5927 65535<\/code>)\uff0c\u5219\u53d6\u5dee\u503c 65535-ldt+now<\/code>\uff1a\u5f53 lru<\/code> now \u65f6\uff0c\u53d6\u5dee\u503c now-ldt<\/code>\uff08\u4e3a\u4e86\u65b9\u4fbf\u540e\u7eed\u8ba1\u7b97\uff0c\u8fd9\u4e2a\u5dee\u503c\u8bb0\u4e3a idle_time <\/code>\uff09\u3002<\/li>\n
                • \u53d6\u51fa\u914d\u7f6e\u6587\u4ef6\u4e2d\u7684 lfu_decay_time<\/code> \u503c\uff0c\u7136\u540e\u8ba1\u7b97\uff1aidle_time \/ lfu_decay_time<\/code>\uff08\u4e3a\u4e86\u65b9\u4fbf\u540e\u7eed\u8ba1\u7b97\uff0c\u8fd9\u4e2a\u503c\u8bb0\u4e3anum_periods<\/code>\uff09\u3002<\/li>\n
                • \u6700\u540e\u5c06counter<\/code>\u51cf\u5c11\uff1acounter - num_periods<\/code>\u3002<\/li>\n<\/ul>\n
                  \u770b\u8d77\u6765\u8fd9\u4e48\u590d\u6742\uff0c\u5176\u5b9e\u8ba1\u7b97\u516c\u5f0f\u5c31\u662f\u4e00\u53e5\u8bdd\uff1a\u53d6\u51fa\u5f53\u524d\u7684\u65f6\u95f4\u6233\u548c\u5bf9\u8c61\u4e2d\u7684 lru<\/code> \u5c5e\u6027\u8fdb\u884c\u5bf9\u6bd4\uff0c\u8ba1\u7b97\u51fa\u5f53\u524d\u591a\u4e45\u6ca1\u6709\u88ab\u8bbf\u95ee\u5230\uff0c\u6bd4\u5982\u8ba1\u7b97\u5f97\u5230\u7684\u7ed3\u679c\u662f 100<\/code> \u5206\u949f\u6ca1\u6709\u88ab\u8bbf\u95ee\uff0c\u7136\u540e\u518d\u53bb\u9664\u914d\u7f6e\u53c2\u6570 lfu_decay_time<\/code>\uff0c\u5982\u679c\u8fd9\u4e2a\u914d\u7f6e\u9ed8\u8ba4\u4e3a 1<\/code>\u4e5f\u5373\u662f 100\/1=100<\/code>\uff0c\u4ee3\u8868 100<\/code> \u5206\u949f\u6ca1\u8bbf\u95ee\uff0c\u6240\u4ee5 counter<\/code> \u5c31\u51cf\u5c11 100<\/code>\u3002<\/p>\n
                  \u603b\u7ed3<\/h2>\n
                  \u672c\u6587\u4e3b\u8981\u4ecb\u7ecd\u4e86 Redis<\/code> \u8fc7\u671f\u952e\u7684\u5904\u7406\u7b56\u7565\uff0c\u4ee5\u53ca\u5f53\u670d\u52a1\u5668\u5185\u5b58\u4e0d\u591f\u65f6 Redis<\/code> \u7684 8<\/code> \u79cd\u6dd8\u6c70\u7b56\u7565\uff0c\u6700\u540e\u4ecb\u7ecd\u4e86 Redis<\/code> \u4e2d\u7684\u4e24\u79cd\u4e3b\u8981\u7684\u6dd8\u6c70\u7b97\u6cd5 LRU<\/code> \u548c LFU<\/code>\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
                  \u6d45\u8c08\u5185\u5b58\u8017\u5c3d\u540eRedis\u4f1a\u53d1\u751f\u4ec0...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-201259","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/201259","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=201259"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/201259\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=201259"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=201259"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=201259"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}