{"id":201610,"date":"2025-05-10T08:00:35","date_gmt":"2025-05-10T00:00:35","guid":{"rendered":"https:\/\/server.hk\/cnblog\/201610\/"},"modified":"2025-05-10T08:00:35","modified_gmt":"2025-05-10T00:00:35","slug":"redis%e6%95%b0%e6%8d%ae%e7%bb%93%e6%9e%84%e7%b1%bb%e5%9e%8b%e7%a4%ba%e4%be%8b%e8%a7%a3%e6%9e%90","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/201610\/","title":{"rendered":"Redis\u6570\u636e\u7ed3\u6784\u7c7b\u578b\u793a\u4f8b\u89e3\u6790"},"content":{"rendered":"

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

Redis\u6570\u636e\u7ed3\u6784\u7c7b\u578b\u793a\u4f8b\u89e3\u6790<\/h1>\n

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

IT\u884c\u4e1a\u76f8\u5bf9\u4e8e\u4e00\u822c\u4f20\u7edf\u884c\u4e1a\uff0c\u53d1\u5c55\u66f4\u65b0\u901f\u5ea6\u66f4\u5feb\uff0c\u4e00\u65e6\u505c\u6b62\u4e86\u5b66\u4e60\uff0c\u5f88\u5feb\u5c31\u4f1a\u88ab\u884c\u4e1a\u6240\u6dd8\u6c70\u3002\u6240\u4ee5\u6211\u4eec\u9700\u8981\u8e0f\u8e0f\u5b9e\u5b9e\u7684\u4e0d\u65ad\u5b66\u4e60\uff0c\u7cbe\u8fdb\u81ea\u5df1\u7684\u6280\u672f\uff0c\u5c24\u5176\u662f\u521d\u5b66\u8005\u3002\u4eca\u5929golang\u5b66\u4e60\u7f51\u7ed9\u5927\u5bb6\u6574\u7406\u4e86\u300aRedis\u6570\u636e\u7ed3\u6784\u7c7b\u578b\u793a\u4f8b\u89e3\u6790\u300b\uff0c\u804a\u804a\u7c7b\u578b\u3001Redis\u6570\u636e\u7ed3\u6784\uff0c\u6211\u4eec\u4e00\u8d77\u6765\u770b\u770b\u5427\uff01<\/p>\n

intset<\/h2>\n

\u5f53set\u96c6\u5408\u5b58\u50a8\u7684\u662f\u6574\u6570\u65f6\uff0cencoding\u4e3aintset\u7c7b\u578b\uff08\u5c0f\u6574\u6570\u96c6\u5408\uff09<\/p>\n

typedef struct intset {\n    int32 encoding;\n    int32 length;\n    int contents[];\n}\n<\/pre>\n\n\n\n\n\n\n
\u5b57\u6bb5<\/th>\n\u63cf\u8ff0<\/th>\n\u8bf4\u660e<\/th>\n<\/tr>\n
encoding<\/td>\n\u51b3\u5b9a\u6574\u6570\u4f4d\u5bbd\u662f16\u4f4d\u300132\u4f4d\u8fd8\u662f64\u4f4d<\/td>\n\u679a\u4e3e\u8868\u793a<\/td>\n<\/tr>\n
length<\/td>\n\u5143\u7d20\u4e2a\u6570<\/td>\n<\/td>\n<\/tr>\n
contents<\/td>\n\u6574\u6570\u6570\u7ec4\uff0c\u5b58\u50a8\u5143\u7d20\u503c<\/td>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
intset\u6309\u7167\u4ece\u5c0f\u5230\u5927\u7684\u987a\u5e8f\u4fdd\u5b58\u5143\u7d20\u3002\u5b58\u50a8\u5143\u7d20\u65f6\uff0c\u6839\u636e\u6574\u6570\u5927\u5c0f\u51b3\u5b9a\u662f\u5426\u8981\u5c06encoding\u5347\u7ea7\uff0c\u627e\u5230\u8981\u63d2\u5165\u5143\u7d20\u7684\u4f4d\u7f6e\uff0c\u5982\u679c\u4e0d\u662f\u6700\u540e\u4e00\u4f4d\uff0c\u4f1a\u5c06\u6240\u5728\u4f4d\u7f6e\u4e4b\u540e\u7684\u5143\u7d20\u540e\u79fb\u4e00\u4f4d\uff0c\u6700\u540e\u63d2\u5165\u5143\u7d20\u3002\u5982\u679c\u63d2\u5165\u7684\u5143\u7d20\u4e0d\u4e3a\u6574\u6570\uff0c\u5b58\u50a8\u5f62\u5f0f\u5c06\u53d8\u6210hash\u7ed3\u6784\u3002<\/p>\n
ziplist<\/h3>\n
\u5f53hash\u4e0ezset\u6ee1\u8db3\u5982\u4e0b\u6761\u4ef6\u6761\u4ef6\u65f6\uff0c\u7f16\u7801\u7c7b\u578b\u4e3aziplist\uff08\u538b\u7f29\u5217\u8868\uff09\uff0c\u5177\u4f53\u53ef\u5728\u914d\u7f6e\u6587\u4ef6\u4e2d\u67e5\u770b\u3002<\/p>\n
hash-max-ziplist-entries 512 # \u5f53hash\u5143\u7d20\u4e2a\u6570\u5c0f\u4e8e512\u65f6\nhash-max-ziplist-value 64 # \u5f53hash\u952e\u6216\u503c\u957f\u5ea6\u5c0f\u4e8e64\u65f6\nzset-max-ziplist-entries 128 # \u5f53zset\u5143\u7d20\u4e2a\u6570\u5c0f\u4e8e128\u65f6\nzset-max-ziplist-value 64 # \u5f53zset\u503c\u5c0f\u4e8e64\u65f6\n<\/pre>\n
typedef struct ziplist {\n    int32 zlbytes;\n    int32 zltail_offset;\n    int16 zllength;\n    T[] entries;\n    int8 zlend;\n}\ntypedef struct entry {\n    int prevlen;\n    int encoding; byte[] content; } <\/pre>\n\n\n\n\n\n\n\n\n
\u5b57\u6bb5<\/th>\n\u63cf\u8ff0<\/th>\n\u8bf4\u660e<\/th>\n<\/tr>\n
zlbytes<\/td>\nziplist\u6240\u5360\u5b57\u8282\u6570<\/td>\n<\/td>\n<\/tr>\n
zltail_offset<\/td>\n\u6700\u540e\u4e00\u4e2a\u5143\u7d20\u8ddd\u79bb\u538b\u7f29\u5217\u8868\u8d77\u59cb\u4f4d\u7f6e\u7684\u504f\u79fb\u91cf<\/td>\n\u7528\u4e8e\u5feb\u901f\u5b9a\u4f4d\u5230\u6700\u540e\u4e00\u4e2a\u8282\u70b9\uff0c\u7136\u540e\u5012\u5e8f\u904d\u5386<\/td>\n<\/tr>\n
zllength<\/td>\n\u5143\u7d20\u4e2a\u6570<\/td>\n<\/td>\n<\/tr>\n
entries<\/td>\n\u538b\u7f29\u5143\u7d20<\/td>\n<\/td>\n<\/tr>\n
zlend<\/td>\n\u6807\u5fd7\u538b\u7f29\u5217\u8868\u7684\u7ed3\u675f<\/td>\n\u6052\u4e3aFF<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n\n\n\n
\u5b57\u6bb5<\/th>\n\u63cf\u8ff0<\/th>\n\u8bf4\u660e<\/th>\n<\/tr>\n
prevlen<\/td>\n\u524d\u4e00\u4e2aentry\u7684\u5b57\u8282\u957f\u5ea6<\/td>\n\u7b2c\u4e00\u4e2aentry\u6052\u4e3a0\uff0c\u5b57\u8282\u957f\u5ea6\u52a8\u6001\u53d8\u5316\uff0c\u5f53\u5b57\u7b26\u4e32\u957f\u5ea6\u5c0f\u4e8e254\u65f6\uff0c\u7528\u4e00\u4e2a\u5b57\u8282\uff0c\u5426\u5219\u7528\u4e94\u4e2a\u5b57\u8282<\/td>\n<\/tr>\n
encoding<\/td>\n\u7f16\u7801\u7c7b\u578b<\/td>\n\u7f16\u7801\u7c7b\u578b\u6839\u636e\u5143\u7d20\u5185\u5bb9\u52a8\u6001\u53d8\u5316\uff0c\u6781\u4e3a\u590d\u6742\uff0c\u672c\u7bc7\u4e0d\u4f5c\u8be6\u7ec6\u63cf\u8ff0\uff0c\u5177\u4f53\u53ef\u641c\u7d22ziplist\u7f16\u7801\u7c7b\u578b<\/td>\n<\/tr>\n
content<\/td>\n\u5143\u7d20\u5185\u5bb9\uff0c\u53ef\u9009<\/td>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\u4e0b\u56fe\u662f\u4e00\u4e2aziplist\u7684demo<\/p>\n
<\/p>\n
    \n
  • \u7b2c1-4\u5b57\u8282\uff0czlbytes\u4e3a25\uff0c\u8bf4\u660e\u8be5\u538b\u7f29\u5217\u8868\u5171\u5360\u752825\u4e2a\u5b57\u8282<\/li>\n
  • \u7b2c5-8\u5b57\u8282\uff0czltail_offset\u4e3a22\uff0c\u8bf4\u660e\u6700\u540e\u4e00\u4e2a\u5143\u7d20\u4ece22\u5f00\u59cb<\/li>\n
  • \u7b2c9-10\u5b57\u8282\uff0czllength\u4e3a3\uff0c\u8bf4\u660e\u5171\u67093\u4e2a\u5143\u7d20<\/li>\n
  • \u7b2c11-16\u5b57\u8282\uff0c\u7b2c\u4e00\u4e2aentry: \u5176\u4e2dprevlen=0\uff0c\u56e0\u4e3a\u5b83\u524d\u9762\u6ca1\u6709\u6570\u636e\u9879\uff1bencoding=4\uff0c\u8868\u793a\u540e\u97624byte\u6309\u7167\u5b57\u7b26\u4e32\u5b58\u50a8\uff0c\u6570\u636e\u7684\u503c\u4e3aname<\/li>\n
  • \u7b2c17-21\u5b57\u8282\uff0c\u7b2c\u4e8c\u4e2aentry: \u5176\u4e2dprevlen=6\uff0c\u8868\u793a\u524d\u4e00\u4e2aentry\u5171\u5360\u75286byte\uff1bencoding=3\uff0c\u8868\u793a\u540e\u97623byte\u6309\u7167\u5b57\u7b26\u4e32\u5b58\u50a8\uff0c\u6570\u636e\u7684\u503c\u4e3awhy<\/li>\n
  • \u7b2c22-24\u5b57\u8282\uff0c\u7b2c\u4e09\u4e2aentry: \u5176\u4e2dprevlen=5\uff0c\u8868\u793a\u524d\u4e00\u4e2aentry\u5171\u5360\u75285byte\uff1bencoding=0xFE\uff0c\u8868\u793a\u540e\u97621byte\u5b58\u50a8\u6574\u6570\uff0c\u6570\u636e\u7684\u503c\u4e3a14<\/li>\n
  • \u7b2c25\u5b57\u8282\uff0czlend\u4e3aFF\uff0c\u6807\u5fd7\u538b\u7f29\u5217\u8868\u7684\u7ed3\u675f<\/li>\n<\/ul>\n
    \u5f53\u7528ziplist\u5b58\u50a8hash\u7ed3\u6784\u65f6\uff0c\u5c06key\u4e0evalue\u5206\u522b\u5f53\u4f5c\u4e00\u4e2aentry\u5b58\u50a8\u3002<\/p>\n
    \u53ef\u89c1\u538b\u7f29\u5217\u8868\u5b58\u50a8\u975e\u5e38\u7684\u7d27\u51d1\uff0c\u5f53\u67d0\u4e00\u4e2aentry\u957f\u5ea6\u53d8\u4e3a254\u65f6\uff0c\u4e0b\u4e00\u4e2aentry\u7684prevlen\u5c06\u4ece1\u4e2a\u5b57\u8282\u6269\u5c55\u52305\u4e2a\u5b57\u8282\uff0c\u8fd9\u5c31\u662f\u7ea7\u8054\u66f4\u65b0<\/strong><\/p>\n
    quicklist<\/h3>\n
    quicklist\uff08\u5feb\u901f\u5217\u8868\uff09\u7528\u4e8e\u5b58\u50a8list\u96c6\u5408\uff0c\u5b83\u662fziplist\u4e0elinkedlist\u7684\u6df7\u5408\u4f53\uff0clinkedlist\u4e0e\u53cc\u5411\u5217\u8868\u7ed3\u6784\u7c7b\u4f3c<\/strong>\u3002<\/p>\n
    quicklist\u5185\u90e8\u9ed8\u8ba4\u5355\u4e2aziplist\u957f\u5ea6\u4e3a8K\uff0c\u8d85\u8fc7\u8fd9\u4e2a\u957f\u5ea6\uff0c\u5c31\u4f1a\u53e6\u8d77\u4e00\u4e2anode\uff0c\u53ef\u5728\u914d\u7f6e\u6587\u4ef6\u4e2d\u914d\u7f6e\u3002<\/p>\n
    # -2\u8868\u793a8k\uff0c\u679a\u4e3e\u7c7b\u578b\u53ef\u5728\u914d\u7f6e\u6587\u4ef6\u4e2d\u67e5\u770b\nlist-max-ziplist-size -2\n<\/pre>\n
    quicklist\u9ed8\u8ba4\u7684\u538b\u7f29\u6df1\u5ea6\u4e3a0\uff0c\u4e5f\u5c31\u662f\u4e0d\u538b\u7f29\u3002\u5982\u679c\u538b\u7f29\u6df1\u5ea6\u4e3a1\uff0c\u90a3\u4e48\u5c31\u662f\u9996\u5c3e\u4e0d\u538b\u7f29\uff0c\u5982\u679c\u538b\u7f29\u6df1\u5ea6\u4e3a2\uff0c\u90a3\u4e48\u5c31\u662f\u99962\u4e2a\u3001\u5c3e2\u4e2a\u4e0d\u538b\u7f29\uff0c\u53ef\u5728\u914d\u7f6e\u6587\u4ef6\u4e2d\u914d\u7f6e\u3002<\/p>\n
    list-compress-depth 0\n<\/pre>\n
    skiplist<\/h3>\n
    zset\u4f7f\u7528dict\u5b58\u50a8value\u4e0escore\u7684\u6620\u5c04\uff0c\u53e6\u4e00\u65b9\u9762\u8fd8\u9700\u8981\u6309\u7167score\u63d0\u4f9b\u6392\u5e8f\u529f\u80fd\uff0c\u4e8e\u662f\u5c31\u6709\u4e86skiplist\uff08\u8df3\u8dc3\u5217\u8868\uff09<\/p>\n
    \u5148\u770bskiplist\u7684\u4e00\u4e2ademo<\/p>\n
    <\/p>\n
    typedef struct zsl {\n    zslnode* header;\n    zslnode* tail;\n    int maxLevel;\n}\n<\/pre>\n
    typedef struct zslnode {\n    sds value;\n    double score;\n    zslforward*[] forwards;\n    zslnode* backward;\n}\n<\/pre>\n
    typedef struct zslforward {\n    zslnode* item;\n    int span;\n}\n<\/pre>\n\n\n\n\n\n\n\n\n\n\n\n
    \u5b57\u6bb5<\/th>\n\u63cf\u8ff0<\/th>\n\u8bf4\u660e<\/th>\n<\/tr>\n
    header<\/td>\n\u6307\u5411\u8df3\u8dc3\u5217\u8868\u7684\u5934\u6307\u9488<\/td>\nvalue\u56fa\u5b9a\u4e3aNULL\uff0cscore\u56fa\u5b9a\u4e3a0\uff0cbackward\u4e3anull<\/td>\n<\/tr>\n
    tail<\/td>\n\u6307\u5411\u8df3\u8dc3\u5217\u8868\u7684\u5c3e\u6307\u9488<\/td>\n<\/td>\n<\/tr>\n
    maxLevel<\/td>\n\u5f53\u524d\u8df3\u8dc3\u8868\u6700\u5927\u5c42\u6570<\/td>\n\u6700\u5927\u4e3a64<\/td>\n<\/tr>\n
    value<\/td>\n\u7528\u4e8e\u5b58\u50a8\u5b57\u7b26\u4e32\u7c7b\u578b\u7684\u6570\u636e<\/td>\n<\/td>\n<\/tr>\n
    score<\/td>\n\u7528\u4e8e\u5b58\u50a8\u5206\u503c<\/td>\n<\/td>\n<\/tr>\n
    backward<\/td>\n\u56de\u9000\u8282\u70b9<\/td>\n\u56fe\u4e2d\u7684\u2190\u7bad\u5934<\/td>\n<\/tr>\n
    forwards<\/td>\n\u524d\u8fdb\u8282\u70b9<\/td>\n\u56fe\u4e2d\u7684\u2192\u7bad\u5934\uff0c\u6bcf\u4e00\u5c42\u5bf9\u5e94\u4e00\u4e2a<\/td>\n<\/tr>\n
    span<\/td>\n\u8de8\u5ea6\uff0c\u5b58\u50a8\u4e00\u4e2a\u8282\u70b9\u8df3\u5230\u4e0b\u4e00\u4e2a\u8282\u70b9\u4e2d\u95f4\u8df3\u8fc7\u4e86\u591a\u5c11\u8282\u70b9<\/td>\n\u5982score1\u6307\u5411score5\uff0c\u5219span\u503c\u4e3a4\uff0c\u8fd9\u662f\u6392\u540d\u7684\u5b9e\u73b0\u539f\u7406<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
    \u6700\u5c0f\u5206\u503c\u7684backward\u56fa\u5b9anull\uff0c\u5bf9\u4e8e\u6bcf\u4e00\u4e2a\u65b0\u63d2\u5165\u7684\u8282\u70b9\uff0c\u4f1a\u8c03\u7528\u4e00\u4e2a\u968f\u673a\u7b97\u6cd5\uff0c\u6765\u7ed9\u5b83\u5206\u914d\u4e00\u4e2a\u5408\u7406\u7684\u5c42\u6570<\/p>\n
    level1\u7684\u6982\u7387\u4e3a1-0.25=0.75<\/code>\uff0c\u5b9e\u9645\u4e3a100%\uff0c\u56e0\u4e3a\u8df3\u8dc3\u5217\u8868\u7684\u6700\u5c0f\u5c42\u6570\u4e3a1<\/p>\n
    level2\u7684\u6982\u7387\u4e3a0.75*0.25=0.1875<\/code>level3\u7684\u6982\u7387\u4e3a0.1875*0.25=0.0468<\/code> ……<\/p>\n
    leveln\u7684\u6982\u7387\u4e3a(1-0.25)*Math.pow(0.25,n-1)<\/code><\/p>\n
    \u603b\u7ed3<\/h2>\n
    Redis\u4f5c\u4e3a\u5355\u7ebf\u7a0b\u5185\u5b58\u670d\u52a1\uff0c\u5728\u54cd\u5e94\u3001\u6570\u636e\u7ed3\u6784\u4e0a\u4f5c\u51fa\u4e86\u5f88\u591a\u7684\u4f18\u5316\uff0c\u503c\u5f97\u6211\u4eec\u5b66\u4e60<\/p>\n\n\n\n\n\n\n\n\n
    \u5bf9\u8c61\u7c7b\u578b<\/th>\n\u7f16\u7801\u7c7b\u578b<\/th>\n<\/tr>\n
    string<\/td>\nint\u3001raw\u3001embstr<\/td>\n<\/tr>\n
    list<\/td>\nquicklist<\/td>\n<\/tr>\n
    hash<\/td>\ndict\u3001ziplist<\/td>\n<\/tr>\n
    set<\/td>\nintset\u3001dict<\/td>\n<\/tr>\n
    zset<\/td>\nziplist\u3001skiplist+dict<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
    HyperLogLog<\/h3>\n
    HyperLogLog\u7684\u539f\u7406\u4e3a\u4f2f\u52aa\u5229\u8bd5\u9a8c\uff0c\u5373\u4e22\u786c\u5e01\uff0c\u6839\u636e\u8fde\u7eed\u51fa\u73b0\u53cd\u9762\u7684\u6b21\u6570X\uff0c\u63a8\u7b97\u51fa\u4e00\u5171\u4e22\u4e862\u7684X\u6b21\u65b9\u6b21\u786c\u5e01\uff0c\u5f53X\u5f88\u5927\u65f6\uff0c\u63a8\u7b97\u51fa\u6765\u7684\u603b\u6570\u4e0e\u5b9e\u9645\u603b\u6570\u8bef\u5dee\u5c31\u5f88\u63a5\u8fd1\u4e86\u3002\u5177\u4f53\u53ef\u67e5\u8be2\u5176\u4ed6\u6587\u7ae0\u3002<\/p>\n
    pfadd<\/h3>\n
    element\u7ecf\u8fc7hash\u7b97\u6cd5\u4e4b\u540e\u662f\u4e00\u4e2a64\u4f4d\u7684\u56fa\u5b9a\u503c<\/p>\n
    \u4f4e14\u4f4d\u4e3a\u6876<\/p>\n
    \u67e5\u627e\u9ad850\u4f4d\u7b2c\u4e00\u4e2a\u4e3a1\u7684\u4f4d\u6570\uff0c\u5982\u679c\u5927\u4e8e\u5f53\u524d\u6876\u7684\u4f4d\u6570\uff0c\u5c31\u5c06\u5176\u8bbe\u7f6e\u4e3a\u5f53\u524d\u6876\u7684\u4f4d\u6570<\/p>\n
    \u5047\u8bbehash\u503c\u662f \uff1a{\u6b64\u5904\u7701\u756545\u4f4d}01100 00000000000101<\/p>\n
      \n
    • \u4f4e14\u4f4d\u7684\u4e8c\u8fdb\u5236\u8f6c\u4e3a10\u8fdb\u5236\uff0c\u503c\u4e3a5\uff08regnum\uff09\uff0c\u5373\u6211\u4eec\u628a\u6570\u636e\u653e\u5728\u7b2c5\u4e2a\u6876<\/li>\n
    • \u9ad850\u4f4d\u7b2c\u4e00\u4e2a1\u7684\u4f4d\u7f6e\u662f3\uff0c\u5373count\u503c\u4e3a3<\/li>\n
    • registers[5]\u53d6\u51fa\u5386\u53f2\u503coldcount<\/li>\n
    • \u5982\u679ccount > oldcount\uff0c\u5219\u66f4\u65b0 registers[5] = count<\/li>\n
    • \u5982\u679ccount <\/li>\n<\/ul>\n
      HyperLogLog\u7528\u4e8616384\u4e2a\u6876\uff0c\u6bcf\u4e2a\u6876\u5360\u75286bit\uff0c\u56e0\u6b64\u8bf4\u4e00\u4e2aHyperLogLog\u6240\u5360\u7528\u5185\u5b58\u662f12K\u3002<\/p>\n
      \u8c03\u548c\u5e73\u5747\u6570\uff1a<\/p>\n
      \u5047\u8bbe\u6211\u7684\u5de5\u8d44\u4e3a10_000\uff0c\u9a6c\u4e91\u7684\u5de5\u8d44\u4e3a1_000_000\uff0c\u90a3\u6211\u548c\u9a6c\u4e91\u7684\u5e73\u5747\u5de5\u8d44\u4e3a505_000\uff0c\u6211\u80af\u5b9a\u662f\u4e0d\u8ba4\u540c\u7684\u3002\u3002\u3002<\/p>\n
      \u5982\u679c\u4f7f\u7528\u8c03\u548c\u5e73\u5747\u6570\uff0c\u5219\u4e3a2\/(1\/10_000+1\/1_000_000)=19_801<\/p>\n
      \u540c\u7406\uff0c\u6876\u4f4d\u6570\u7684\u5e73\u5747\u6570\u4e3a\uff1an\/(1\/\u68761\u4f4d\u6570+1\/\u68762\u4f4d\u6570+…+1\/\u6876n\u4f4d\u6570)<\/p>\n
      \u6876\u7684\u5e73\u5747\u4e2a\u6570\u4e3a\uff1aMath.pow(2\uff0c\u6876\u4f4d\u6570\u7684\u5e73\u5747\u6570)<\/p>\n
      \u603b\u6570\u91cf\uff1aconst*\u6876\u603b\u6570n*\u6876\u7684\u5e73\u5747\u4e2a\u6570\uff0c\u5176\u4e2dconstant\u4e3a\u4e0d\u5b9a\u503c\uff0c\u4e0e\u6876\u4e2a\u6570\u6709\u5173\uff0c\u5047\u8bbem\u4e3a\u6876\u4e2a\u6570\uff0c\u53d6\u5bf9\u6570<\/p>\n
      pfcount<\/h3>\n
      p=log2m\nswitch (p) {\n   case 4:\n       constant = 0.673 * m * m;\n   case 5:\n       constant = 0.697 * m * m;\n   case 6:\n       constant = 0.709 * m * m;\n   default:\n       constant = (0.7213 \/ (1 + 1.079 \/ m)) * m * m;\n}<\/pre>\n","protected":false},"excerpt":{"rendered":"
      Redis\u6570\u636e\u7ed3\u6784\u7c7b\u578b\u793a\u4f8b\u89e3\u6790 ...<\/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-201610","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/201610","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=201610"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/201610\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=201610"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=201610"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=201610"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}