\u6570\u636e\u5e93\u5c0f\u767d\u4e00\u679a\uff0c\u6b63\u5728\u4e0d\u65ad\u5b66\u4e60\u79ef\u7d2f\u77e5\u8bc6\uff0c\u73b0\u5c06\u5b66\u4e60\u5230\u7684\u77e5\u8bc6\u8bb0\u5f55\u4e00\u4e0b\uff0c\u4e5f\u662f\u5c06\u6211\u7684\u6240\u5f97\u5206\u4eab\u7ed9\u5927\u5bb6\uff01\u800c\u4eca\u5929\u8fd9\u7bc7\u6587\u7ae0\u300a\u5728Redis\u4e2d\uff0c\u5982\u4f55\u8fd0\u7528\u7f13\u5b58\u6dd8\u6c70\u7b56\u7565\u548c\u4e8b\u52a1\u5b9e\u73b0\u4e50\u89c2\u9501\uff1f\u300b\u5e26\u5927\u5bb6\u6765\u4e86\u89e3\u4e00\u4e0b##content_title##\uff0c\u5e0c\u671b\u5bf9\u5927\u5bb6\u7684\u77e5\u8bc6\u79ef\u7d2f\u6709\u6240\u5e2e\u52a9\uff0c\u4ece\u800c\u5f25\u8865\u81ea\u5df1\u7684\u4e0d\u8db3\uff0c\u52a9\u529b\u5b9e\u6218\u5f00\u53d1\uff01<\/p>\n
<\/p>\n
- \n
- \n
\u65b0\u6570\u636e\u63d2\u5165\u5230\u94fe\u8868\u5934\u90e8\uff1b<\/p>\n<\/li>\n
- \n
\u6bcf\u5f53\u7f13\u5b58\u547d\u4e2d\uff08\u5373\u7f13\u5b58\u6570\u636e\u88ab\u8bbf\u95ee\uff09\uff0c\u5219\u5c06\u6570\u636e\u79fb\u5230\u94fe\u8868\u5934\u90e8\uff1b<\/p>\n<\/li>\n
- \n
\u5f53\u94fe\u8868\u6ee1\u7684\u65f6\u5019\uff0c\u5c06\u94fe\u8868\u5c3e\u90e8\u7684\u6570\u636e\u4e22\u5f03\u3002<\/p>\n<\/li>\n<\/ul>\n
\u5728Java\u4e2d\u53ef\u4ee5\u4f7f\u7528LinkHashMap\u53bb\u5b9e\u73b0LRU\u5229\u7528\u54c8\u5e0c\u94fe\u8868\u5b9e\u73b0\uff1a<\/strong><\/p>\n
![](\"https:\/\/www.17golang.com\/uploads\/20230510\/1683700203645b39eb27580.png\")
<\/p>\n\u6807\u9898Redis\u7f13\u5b58\u6dd8\u6c70\u7b56\u7565<\/h3>\n
\u8bbe\u7f6e\u6700\u5927\u7f13\u5b58<\/h4>\n
\n
\u5728 redis \u4e2d\uff0c\u5141\u8bb8\u7528\u6237\u8bbe\u7f6e\u6700\u5927\u4f7f\u7528\u5185\u5b58\u5927\u5c0fmaxmemory\uff0c\u9ed8\u8ba4\u4e3a0\uff0c\u6ca1\u6709\u6307\u5b9a\u6700\u5927\u7f13\u5b58\uff0c\u5982\u679c\u6709\u65b0\u7684\u6570\u636e\u6dfb\u52a0\uff0c\u8d85\u8fc7\u6700\u5927\u5185\u5b58\uff0c\u5219\u4f1a\u4f7fredis\u5d29\u6e83\uff0c\u6240\u4ee5\u4e00\u5b9a\u8981\u8bbe\u7f6e\u3002<\/p>\n<\/blockquote>\n
redis \u5185\u5b58\u6570\u636e\u96c6\u5927\u5c0f\u4e0a\u5347\u5230\u4e00\u5b9a\u5927\u5c0f\u7684\u65f6\u5019\uff0c\u5c31\u4f1a\u5b9e\u884c\u6570\u636e\u6dd8\u6c70\u7b56\u7565\u3002<\/p>\n
\u6dd8\u6c70\u7b56\u7565<\/h4>\n
\n
redis\u6dd8\u6c70\u7b56\u7565\u914d\u7f6e\uff1amaxmemory-policy voltile-lru\uff0c\u652f\u6301\u70ed\u914d\u7f6e<\/p>\n<\/blockquote>\n
redis \u63d0\u4f9b 6\u79cd\u6570\u636e\u6dd8\u6c70\u7b56\u7565\uff1a<\/strong><\/p>\n
- \n
- \n
volatile-lru\uff1a<\/strong>\u4ece\u5df2\u8bbe\u7f6e\u8fc7\u671f\u65f6\u95f4\u7684\u6570\u636e\u96c6\uff08server.db[i].expires\uff09\u4e2d\u6311\u9009\u6700\u8fd1\u6700\u5c11\u4f7f\u7528\u7684\u6570\u636e\u6dd8\u6c70<\/p>\n<\/li>\n
- \n
volatile-ttl\uff1a<\/strong>\u4ece\u5df2\u8bbe\u7f6e\u8fc7\u671f\u65f6\u95f4\u7684\u6570\u636e\u96c6\uff08server.db[i].expires\uff09\u4e2d\u6311\u9009\u5c06\u8981\u8fc7\u671f\u7684\u6570\u636e\u6dd8\u6c70<\/p>\n<\/li>\n
- \n
volatile-random\uff1a<\/strong>\u4ece\u5df2\u8bbe\u7f6e\u8fc7\u671f\u65f6\u95f4\u7684\u6570\u636e\u96c6\uff08server.db[i].expires\uff09\u4e2d\u4efb\u610f\u9009\u62e9\u6570\u636e\u6dd8\u6c70<\/p>\n<\/li>\n
- \n
allkeys-lru\uff1a<\/strong>\u4ece\u6570\u636e\u96c6\uff08server.db[i].dict\uff09\u4e2d\u6311\u9009\u6700\u8fd1\u6700\u5c11\u4f7f\u7528\u7684\u6570\u636e\u6dd8\u6c70<\/p>\n<\/li>\n
- \n
allkeys-random\uff1a<\/strong>\u4ece\u6570\u636e\u96c6\uff08server.db[i].dict\uff09\u4e2d\u4efb\u610f\u9009\u62e9\u6570\u636e\u6dd8\u6c70<\/p>\n<\/li>\n
- \n
no-enviction\uff08\u9a71\u9010\uff09\uff1a<\/strong>\u7981\u6b62\u9a71\u9010\u6570\u636e<\/p>\n<\/li>\n<\/ul>\n
Redis\u4e8b\u52a1<\/h3>\n
Redis\u4e8b\u52a1\u4ecb\u7ecd<\/h4>\n
- \n
- \n
Redis \u7684\u4e8b\u52a1\u662f\u901a\u8fc7 MULTI \u3001 EXEC \u3001 DISCARD \u548c WATCH \u3001UNWATCH\u8fd9\u4e94\u4e2a\u547d\u4ee4\u6765\u5b8c\u6210\u7684\u3002<\/p>\n<\/li>\n
- \n
Redis \u7684\u5355\u4e2a\u547d\u4ee4\u90fd\u662f\u539f\u5b50\u6027\u7684\uff0c\u6240\u4ee5\u8fd9\u91cc\u9700\u8981\u786e\u4fdd\u4e8b\u52a1\u6027\u7684\u5bf9\u8c61\u662f\u547d\u4ee4\u96c6\u5408\u3002<\/p>\n<\/li>\n
- \n
Redis \u5c06\u547d\u4ee4\u96c6\u5408\u5e8f\u5217\u5316\u5e76\u786e\u4fdd\u5904\u4e8e\u540c\u4e00\u4e8b\u52a1\u7684\u547d\u4ee4\u96c6\u5408\u8fde\u7eed\u4e14\u4e0d\u88ab\u6253\u65ad\u7684\u6267\u884c<\/p>\n<\/li>\n
- \n
Redis \u4e0d\u652f\u6301\u56de\u6eda\u64cd\u4f5c\u3002 \u4e8b\u52a1\u547d\u4ee4<\/p>\n<\/li>\n<\/ul>\n
MULTI<\/h4>\n
\u7528\u4e8e\u6807\u8bb0\u4e8b\u52a1\u5757\u7684\u5f00\u59cb\u3002Redis\u4f1a\u9010\u4e2a\u5c06\u540e\u7eed\u547d\u4ee4\u653e\u5165\u961f\u5217\u4e2d\uff0c\u968f\u540e\u4f7f\u7528EXEC\u547d\u4ee4\u4ee5\u539f\u5b50\u5316\u65b9\u5f0f\u6267\u884c\u8be5\u547d\u4ee4\u5e8f\u5217\u3002<\/p>\n
\u8bed\u6cd5\uff1a<\/strong><\/p>\n
multi<\/pre>\n
EXEC<\/h4>\n
\u5728\u4e00\u4e2a\u4e8b\u52a1\u4e2d\u6267\u884c\u6240\u6709\u5148\u524d\u653e\u5165\u961f\u5217\u7684\u547d\u4ee4\uff0c\u7136\u540e\u6062\u590d\u6b63\u5e38\u7684\u8fde\u63a5\u72b6\u6001<\/p>\n
\u8bed\u6cd5\uff1a<\/strong><\/p>\n
exec<\/pre>\n
DISCARD<\/h4>\n
\u6e05\u9664\u6240\u6709\u5148\u524d\u5728\u4e00\u4e2a\u4e8b\u52a1\u4e2d\u653e\u5165\u961f\u5217\u7684\u547d\u4ee4\uff0c\u7136\u540e\u6062\u590d\u6b63\u5e38\u7684\u8fde\u63a5\u72b6\u6001\u3002<\/p>\n
\u8bed\u6cd5\uff1a<\/strong><\/p>\n
discard<\/pre>\n
WATCH<\/h4>\n
\u5f53\u67d0\u4e2a[\u4e8b\u52a1\u9700\u8981\u6309\u6761\u4ef6\u6267\u884c]\u65f6\uff0c\u5c31\u8981\u4f7f\u7528\u8fd9\u4e2a\u547d\u4ee4\u5c06\u7ed9\u5b9a\u7684[\u952e\u8bbe\u7f6e\u4e3a\u53d7\u76d1\u63a7]\u7684\u72b6\u6001\u3002<\/p>\n
\u8bed\u6cd5\uff1a<\/strong><\/p>\n
watch key [key\u2026]<\/pre>\n
\u6ce8\u610f\u4e8b\u9879\uff1a<\/strong>\u4f7f\u7528\u8be5\u547d\u4ee4\u53ef\u4ee5\u5b9e\u73b0 Redis \u7684\u4e50\u89c2\u9501\u3002<\/p>\n
UNWATCH<\/p>\n
\u6e05\u9664\u6240\u6709\u5148\u524d\u4e3a\u4e00\u4e2a\u4e8b\u52a1\u76d1\u63a7\u7684\u952e<\/p>\n
\u8bed\u6cd5\uff1a<\/strong><\/p>\n
unwatch<\/pre>\n
\u547d\u4ee4\u56fe\u89e3\uff1a<\/strong><\/p>\n
![](\"https:\/\/www.17golang.com\/uploads\/20230510\/1683700203645b39eb315d8.png\")
<\/p>\n\u4e8b\u52a1\u6f14\u793a\uff1a<\/strong><\/p>\n
127.0.0.1:6379> multi\nOK\n127.0.0.1:6379> set s1 111\nQUEUED\n127.0.0.1:6379> hset set1 name zhangsan\nQUEUED\n127.0.0.1:6379> exec\n1) OK\n2) (integer) 1\n127.0.0.1:6379> multi\nOK\n127.0.0.1:6379> set s2 222\nQUEUED\n127.0.0.1:6379> hset set2 age 20\nQUEUED\n127.0.0.1:6379> discard\nOK\n127.0.0.1:6379> exec (error) ERR EXEC without MULTI \n127.0.0.1:6379> watch s1\nOK\n127.0.0.1:6379> multi\nOK\n127.0.0.1:6379> set s1 555\nQUEUED 127.0.0.1:6379> exec # \u6b64\u65f6\u5728\u6ca1\u6709exec\u4e4b\u524d\uff0c\u901a\u8fc7\u53e6\u4e00\u4e2a\u547d\u4ee4\u7a97\u53e3\u5bf9\u76d1\u63a7\u7684s1\u5b57\u6bb5\u8fdb\u884c\u4fee\u6539 \n(nil)\n127.0.0.1:6379> get s1\n111<\/pre>\n
Redis \u4e0d\u652f\u6301\u4e8b\u52a1\u56de\u6eda\uff08\u4e3a\u4ec0\u4e48\u5462\uff09<\/h4>\n
\u5927\u591a\u6570\u4e8b\u52a1\u5931\u8d25\u662f\u56e0\u4e3a\u8bed\u6cd5\u9519\u8bef\u6216\u8005\u7c7b\u578b\u9519\u8bef\uff0c\u8fd9\u4e24\u79cd\u9519\u8bef\uff0c\u5728\u5f00\u53d1\u9636\u6bb5\u90fd\u662f\u53ef\u4ee5\u9884\u89c1\u7684Redis \u4e3a\u4e86\u6027\u80fd\u65b9\u9762\u5c31\u5ffd\u7565\u4e86\u4e8b\u52a1\u56de\u6eda\u3002<\/p>\n
Redis\u4e50\u89c2\u9501<\/h4>\n
\u4e50\u89c2\u9501\u57fa\u4e8eCAS\uff08Compare And Swap\uff09\u601d\u60f3\uff08\u6bd4\u8f83\u5e76\u66ff\u6362\uff09\uff0c\u662f\u4e0d\u5177\u6709\u4e92\u65a5\u6027\uff0c\u4e0d\u4f1a\u4ea7\u751f\u9501\u7b49\u5f85\u800c\u6d88\u8017\u8d44\u6e90\uff0c\u4f46\u662f\u9700\u8981\u53cd\u590d\u7684\u91cd\u8bd5\uff0c\u4f46\u4e5f\u662f\u56e0\u4e3a\u91cd\u8bd5\u7684\u673a\u5236\uff0c\u80fd\u6bd4\u8f83\u5feb\u7684\u54cd\u5e94\u3002\u56e0\u6b64\u6211\u4eec\u53ef\u4ee5\u5229\u7528redis\u6765<\/p>\n
\u5b9e\u73b0\u4e50\u89c2\u9501\u3002\u5177\u4f53\u601d\u8def\u5982\u4e0b\uff1a<\/strong><\/p>\n
- \n
- \n
\u5229\u7528redis\u7684watch\u529f\u80fd\uff0c\u76d1\u63a7\u8fd9\u4e2aredisKey\u7684\u72b6\u6001\u503c<\/p>\n<\/li>\n
- \n
\u83b7\u53d6redisKey\u7684\u503c<\/p>\n<\/li>\n
- \n
\u521b\u5efaredis\u4e8b\u52a1<\/p>\n<\/li>\n
- \n
\u7ed9\u8fd9\u4e2akey\u7684\u503c+1<\/p>\n<\/li>\n
- \n
\u7136\u540e\u53bb\u6267\u884c\u8fd9\u4e2a\u4e8b\u52a1\uff0c\u5982\u679ckey\u7684\u503c\u88ab\u4fee\u6539\u8fc7\u5219\u56de\u6eda\uff0ckey\u4e0d\u52a01<\/p>\n<\/li>\n<\/ul>\n
public void watch() {\n\ttry {\n\t\tString watchKeys = \"watchKeys\";\n\t\t\/\/\u521d\u59cb\u503c value=1\n\t\tjedis.set(watchKeys, 1);\n\t\t\/\/\u76d1\u542ckey\u4e3awatchKeys\u7684\u503c\n\t\tjedis.watch(watchkeys);\n\t\t\/\/\u5f00\u542f\u4e8b\u52a1\n\t\tTransaction tx = jedis.multi();\n\t\t\/\/watchKeys\u81ea\u589e\u52a0\u4e00\n\t\ttx.incr(watchKeys);\n\t\t\/\/\u6267\u884c\u4e8b\u52a1\uff0c\u5982\u679c\u5176\u4ed6\u7ebf\u7a0b\u5bf9watchKeys\u4e2d\u7684value\u8fdb\u884c\u4fee\u6539\uff0c\u5219\u8be5\u4e8b\u52a1\u5c06\u4e0d\u4f1a\u6267\u884c\n\t\t\/\/\u901a\u8fc7redis\u4e8b\u52a1\u4ee5\u53cawatch\u547d\u4ee4\u5b9e\u73b0\u4e50\u89c2\u9501\n\t\tList<Object> exec = tx.exec();\n\t\tif (exec == null) {\n\t\t\tSystem.out.println(\"\u4e8b\u52a1\u672a\u6267\u884c\");\n\t\t} else {\n\t\t\tSystem.out.println(\"\u4e8b\u52a1\u6210\u529f\u6267\u884c\uff0cwatchKeys\u7684value\u6210\u529f\u4fee\u6539\");\n\t\t}\n\t} catch (Exception e) {\n\t\te.printStackTrace();\n\t} finally {\n\t\tjedis.close();\n\t}\n}<\/pre>\nRedis\u4e50\u89c2\u9501\u5b9e\u73b0\u79d2\u6740<\/h3>\n
public class RedisLock {\n public static void main(String[] arg) {\n \/\/\u5e93\u5b58key \n String redisKey = \"stock\";\n ExecutorService executorService = Executors.newFixedThreadPool(20);\n try {\n Jedis jedis = new RedisProperties.Jedis(\"127.0.0.1\", 6378);\n \/\/ \u53ef\u4ee5\u88ab\u79d2\u6740\u7684\u5e93\u5b58\u7684\u521d\u59cb\u503c\uff0c\u5e93\u5b58\u603b\u517120\u4e2a\n jedis.set(redisKey, \"0\");\n jedis.close();\n } catch (Exception e) {\n e.printStackTrace();\n }\n for (int i = 0; i < 1000; i++) {\n executorService.execute(() -> {\n Jedis jedis1 = new Jedis(\"127.0.0.1\", 6378);\n try {\n jedis1.watch(redisKey);\n String redisValue = jedis1.get(redisKey);\n int valInteger = Integer.valueOf(redisValue);\n String userInfo = UUID.randomUUID().toString();\n \/\/ \u6ca1\u6709\u79d2\u5b8c\n if (valInteger < 20) {\n Transaction tx = jedis1.multi();\n tx.incr(redisKey);\n List list = tx.exec();\n \/\/ \u79d2\u6210\u529f \u5931\u8d25\u8fd4\u56de\u7a7alist\u800c\u4e0d\u662f\u7a7a\n if (list != null && list.size() > 0) {\n System.out.println(\"\u7528\u6237\uff1a\" + userInfo + \"\uff0c\u79d2\u6740\u6210 \u529f\uff01\u5f53\u524d\u6210\u529f\u4eba\u6570\uff1a\" + (valInteger + 1));\n }\n \/\/ \u7248\u672c\u53d8\u5316\uff0c\u88ab\u522b\u4eba\u62a2\u4e86\u3002\n else {\n System.out.println(\"\u7528\u6237\uff1a\" + userInfo + \"\uff0c\u79d2\u6740\u5931 \u8d25\");\n }\n }\n \/\/ \u79d2\u5b8c\u4e86\n else {\n System.out.println(\"\u5df2\u7ecf\u670920\u4eba\u79d2\u6740\u6210\u529f\uff0c\u79d2\u6740\u7ed3\u675f\");\n }\n } catch (Exception e) {\n e.printStackTrace();\n } finally {\n jedis1.close();\n }\n });\n }\n executorService.shutdown();\n }\n}<\/pre>\n","protected":false},"excerpt":{"rendered":"\u5728Redis\u4e2d\uff0c\u5982\u4f55\u8fd0\u7528\u7f13\u5b58\u6dd8\u6c70...<\/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-201703","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/201703","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=201703"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/201703\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=201703"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=201703"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=201703"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
- \n
- \n
- \n
- <\/ul>\n<\/ul>\n
\u7f13\u5b58\u6dd8\u6c70\u7b56\u7565<\/h3>\n\u6807\u9898LRU\u539f\u7406<\/h4>\n
LRU\uff08Least recently used\uff0c\u6700\u8fd1\u6700\u5c11\u4f7f\u7528\uff09\u7b97\u6cd5\u6839\u636e\u6570\u636e\u7684\u5386\u53f2\u8bbf\u95ee\u8bb0\u5f55\u6765\u8fdb\u884c\u6dd8\u6c70\u6570\u636e\uff0c\u5176\u6838\u5fc3\u601d\u60f3\u662f\u201c\u5982\u679c\u6570\u636e\u6700\u8fd1\u88ab\u8bbf\u95ee\u8fc7\uff0c\u90a3\u4e48\u5c06\u6765\u88ab\u8bbf\u95ee\u7684\u51e0\u7387\u4e5f\u66f4\u9ad8\u201d\u3002<\/p>\n
\u6700\u5e38\u89c1\u7684\u5b9e\u73b0\u662f\u4f7f\u7528\u4e00\u4e2a\u94fe\u8868\u4fdd\u5b58\u7f13\u5b58\u6570\u636e\uff0c\u8be6\u7ec6\u7b97\u6cd5\u5b9e\u73b0\u5982\u4e0b\uff1a<\/strong><\/p>\n![](\"https:\/\/www.17golang.com\/uploads\/20230510\/1683700203645b39eb1c605.png\")
<\/p>\n\n