利用多线程解决生成券性能问题

叁歲伎倆 2022-07-11 07:13 97阅读 0赞

第一步：根据活动id查询所有已生成的券，并根据券总数生成未生成的券（性能问题不在这边）

/**
       * 普通生成券的方法
       * 
       * @param promotionActivityListVo
       * @return
       */
      private int generateCouponByActivityId(PromotionActivityListVo promotionActivityListVo, final int nums) {
        try {
          //生成券开始
          String sql = generateSimpleInsertCouponSql(promotionActivityListVo);
          List<String> params = new ArrayList<String>();
          List<String> couponNos = couponTemplateDao.getCouponNoByPromotionId(promotionActivityListVo.getId());
          Set<String> couponVoSet = new HashSet<String>(couponNos.size());
          for (String counponNo : couponNos) {
            couponVoSet.add(counponNo);
          }
          int i = 0;
          while (i < nums) {
            String couponNo = promotionActivityListVo.getCouponCode() + com.szy.utils.RandomStringUtils.getRandomString(4);
            boolean compareFlag = couponVoSet.contains(couponNo);
            if (compareFlag == false) {
              i++;
              params.add(couponNo);
              couponVoSet.add(couponNo);
            }
          }
          //生成券结束
    
          //把券插入数据库（性能问题出在这  如一次生成200万 没有用多线程并且没有用spring的批量提交时要4个小时）
          //（换成多线程和spring的批量插入只要10分钟）    
          return params.size();
          }
        } catch (Exception e) {
          log.error(e);
          return 0;
        }
        return 0;
      }

第二步：把券插入数据库，把总记录数分成多个线程分批插入数据库，用CountDownLatch同步线程

if (params.size() > 0) {
            int[] indexs = ThreadUtils.getIndex(params.size(), 1000, 10);//分配线程数
            CountDownLatch latch = new CountDownLatch(indexs.length - 1);
            for (int j = 1; j < indexs.length; j++) {
              taskExecutor.execute(new SaveCouponNoTask(latch, sql, params.subList(indexs[j - 1], indexs[j])));
            }
            new StatCouponNoSaveTask(latch, System.currentTimeMillis()).doTask();
            // 如果是商品券，则将本活动生成的券号插入到redis中,便于后续批量随机取值,赠送券不用
            if (promotionActivityListVo.getCommodityType() == 2) {
              // 生成券和获取券使用同一个锁锁住，避免在获取券且使用脚标删除的过程中会将新生成的券删除掉
              String lockCouponNoKey = "PromotionActivity:" + promotionActivityListVo.getId() + ":getEnableCoupon";
              String uuid = UUID.randomUUID().toString().replaceAll("-", "");
              if (RedisUtils.getLock(lockCouponNoKey, uuid, 10)) {
                try {
                  String batchCouponNoKey = "PromotionActivity:" + promotionActivityListVo.getId() + ":couponSet";
                  Set<String> couponNosSet = new HashSet(params);
                  CouponToRedisUtils.couponToRedis(batchCouponNoKey, couponNosSet);
                } catch (Exception e) {
                  log.error("生成商品券插入redis中失败！错误：" + e.getMessage());
                } finally {
                  RedisUtils.unlock(lockCouponNoKey, uuid);
                }
              }
     }

第三步：线程任务所做的事情

@Override
      public void run() {
        try {
          int each = 10000;
          int times = Double.valueOf(Math.floor(params.size() / each)).intValue();
          int totalCount = 0;
          for (int i = 0; i < times; i++) {
            int beforeCount = totalCount;
            totalCount += each;
    //        System.out.println("线程开始执行，ID:" + Thread.currentThread().getId() + "，当前时间：" + System.currentTimeMillis());
            couponTemplateBiz.batchInsertCoupon(sql, params.subList(beforeCount, totalCount));
    //        System.out.println("线程ID:" + Thread.currentThread().getId() + "，当前时间：" + System.currentTimeMillis());
          }
          if (totalCount < params.size()) {
            couponTemplateBiz.batchInsertCoupon(sql, params.subList(totalCount, params.size()));
          }
        } catch (Exception e) {
          logger.error("生成券插入数据库异常", e);
        } finally {
          latch.countDown();
        }
      }

public int batchInsertCoupon(String sql, final List<String> params) {
        int[] count = jdbcTemplate.batchUpdate(sql, new BatchPreparedStatementSetter() {
          public void setValues(PreparedStatement ps, int i) throws SQLException {
            ps.setString(1, params.get(i));
          }
    
          public int getBatchSize() {
            return params.size();
          }
        });
        return count.length;
      }