cosbench單機多worker成功率低問題，查看後臺日誌：
2017-07-13 19:02:55,270 [ERROR] [AbstractOperator] - worker 2 fail to perform operation s3testx1/myobjects3
com.amazonaws.AmazonClientException: Unable to verify integrity of data download. Client calculated content hash didn't match hash calculated by Amazon S3. The data may be corrupt.
at com.amazonaws.services.s3.internal.DigestValidationInputStream.validateMD5Digest(DigestValidationInputStream.java:79)
at com.amazonaws.services.s3.internal.DigestValidationInputStream.read(DigestValidationInputStream.java:61)
at com.amazonaws.internal.SdkFilterInputStream.read(SdkFilterInputStream.java:72)
at com.amazonaws.services.s3.model.S3ObjectInputStream.read(S3ObjectInputStream.java:155)
at com.amazonaws.services.s3.model.S3ObjectInputStream.read(S3ObjectInputStream.java:147)
at com.intel.cosbench.driver.operator.Reader.copyLarge(Reader.java:120)
at com.intel.cosbench.driver.operator.Reader.doRead(Reader.java:92)
at com.intel.cosbench.driver.operator.Reader.operate(Reader.java:69)
at com.intel.cosbench.driver.operator.AbstractOperator.operate(AbstractOperator.java:76)
at com.intel.cosbench.driver.agent.WorkAgent.performOperation(WorkAgent.java:197)
at com.intel.cosbench.driver.agent.WorkAgent.doWork(WorkAgent.java:177)
at com.intel.cosbench.driver.agent.WorkAgent.execute(WorkAgent.java:134)
at com.intel.cosbench.driver.agent.AbstractAgent.call(AbstractAgent.java:44)
at com.intel.cosbench.driver.agent.AbstractAgent.call(AbstractAgent.java:1)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:748)
解決辦法：
- 編輯 cosbench-start.sh 文件,找到java啓動命令行參數, 增加"-Dcom.amazonaws.services.s3.disableGetObjectMD5Validation=true" 關閉S3的MD5校驗功能
- 重啓cosbench