详解利用redis + lua解决抢红包高并发的问题

-- 函数：尝试获得红包，如果成功，则返回json字符串，如果不成功，则返回空 -- 参数：红包队列名， 已消费的队列名，去重的Map名，用户ID -- 返回值：nil 或者 json字符串，包含用户ID：userId，红包ID：id，红包金额：money  -- 如果用户已抢过红包，则返回nil if rediscall('hexists', KEYS[3], KEYS[4]) ~= 0 then  return nil else  -- 先取出一个小红包  local hongBao = rediscall('rpop', KEYS[1]);  if hongBao then   local x = cjsondecode(hongBao);   -- 加入用户ID信息   x['userId'] = KEYS[4];   local re = cjsonencode(x);   -- 把用户ID放到去重的set里   rediscall('hset', KEYS[3], KEYS[4], KEYS[4]);   -- 把红包放到已消费队列里   rediscall('lpush', KEYS[2], re);   return re;  end end return nil 

public class TestEval {   static String host = "localhost";   static int honBaoCount = 1_0_0000;      static int threadCount = 20;      static String hongBaoList = "hongBaoList";   static String hongBaoConsumedList = "hongBaoConsumedList";   static String hongBaoConsumedMap = "hongBaoConsumedMap";      static Random random = new Random();    // -- 函数：尝试获得红包，如果成功，则返回json字符串，如果不成功，则返回空 // -- 参数：红包队列名， 已消费的队列名，去重的Map名，用户ID // -- 返回值：nil 或者 json字符串，包含用户ID：userId，红包ID：id，红包金额：money   static String tryGetHongBaoScript =  //     "local bConsumed = rediscall('hexists', KEYS[3], KEYS[4]);/n" //     + "print('bConsumed:' ,bConsumed);/n"       "if rediscall('hexists', KEYS[3], KEYS[4]) ~= 0 then/n"       + "return nil/n"       + "else/n"       + "local hongBao = rediscall('rpop', KEYS[1]);/n" //     + "print('hongBao:', hongBao);/n"       + "if hongBao then/n"       + "local x = cjsondecode(hongBao);/n"       + "x['userId'] = KEYS[4];/n"       + "local re = cjsonencode(x);/n"       + "rediscall('hset', KEYS[3], KEYS[4], KEYS[4]);/n"       + "rediscall('lpush', KEYS[2], re);/n"       + "return re;/n"       + "end/n"       + "end/n"       + "return nil";   static StopWatch watch = new StopWatch();      public static void main(String[] args) throws InterruptedException { //   testEval();     generateTestData();     testTryGetHongBao();   }      static public void generateTestData() throws InterruptedException {     Jedis jedis = new Jedis(host);     jedisflushAll();     final CountDownLatch latch = new CountDownLatch(threadCount);     for(int i = 0; i < threadCount; ++i) {       final int temp = i;       Thread thread = new Thread() {         public void run() {           Jedis jedis = new Jedis(host);           int per = honBaoCount/threadCount;           JSONObject object = new JSONObject();           for(int j = temp * per; j < (temp+1) * per; j++) {             objectput("id", j);             objectput("money", j);             jedislpush(hongBaoList, objecttoJSONString());           }           latchcountDown();         }       };       threadstart();     }     latchawait();   }      static public void testTryGetHongBao() throws InterruptedException {     final CountDownLatch latch = new CountDownLatch(threadCount);     Systemerrprintln("start:" + SystemcurrentTimeMillis()/1000);     watchstart();     for(int i = 0; i < threadCount; ++i) {       final int temp = i;       Thread thread = new Thread() {         public void run() {           Jedis jedis = new Jedis(host);           String sha = jedisscriptLoad(tryGetHongBaoScript);           int j = honBaoCount/threadCount * temp;           while(true) {             Object object = jediseval(tryGetHongBaoScript, 4, hongBaoList, hongBaoConsumedList, hongBaoConsumedMap, "" + j);             j++;             if (object != null) { //             Systemoutprintln("get hongBao:" + object);             }else {               //已经取完了               if(jedisllen(hongBaoList) == 0)                 break;             }           }           latchcountDown();         }       };       threadstart();     }          latchawait();     watchstop();          Systemerrprintln("time:" + watchgetTotalTimeSeconds());     Systemerrprintln("speed:" + honBaoCount/watchgetTotalTimeSeconds());     Systemerrprintln("end:" + SystemcurrentTimeMillis()/1000);   } }