現象:
WriteResult res = mongoTemplate.updateFirst(query, updateObj, "ServerToAgentReq_SMS");
擷取res.getN()傳回值時,發現偶爾情況下該傳回值為0,表示該更新操作沒有更新到任何資料。並且如果是多線程並發更新,失敗幾率大大提高。
官網表示不能保證更新操作的成功性....
方案:
一次失敗後,另起線程多次重試。
private ThreadPoolExecutor exec = new ThreadPoolExecutor(2, 10, 3, TimeUnit.SECONDS, new ArrayBlockingQueue<Runnable>(10), new ThreadPoolExecutor.CallerRunsPolicy());主要代碼: WriteResult res = mongoTemplate.updateFirst(query, updateObj, "ServerToAgentReq_SMS"); //如果更新失敗,進入其他線程重試更新 if (res.getN() == 0) { exec.execute(new Runnable() { @Override public void run() { int num = 0; WriteResult res = mongoTemplate.updateFirst(query, updateObj, "ServerToAgentReq_SMS"); while (res.getN() == 0 && num < 100) { res = mongoTemplate.updateFirst(query, updateObj, "ServerToAgentReq_SMS"); num++; try { Thread.sleep(300); } catch (InterruptedException e) { logger.error("響應更新失敗{}", e); } } if (res.getN() == 0) { logger.error("響應更新失敗!!!gwMsgId:{},masMsgId:{}", gwMsgId, masMsgId); } } });
如此失敗率,大大減少。