private bool IsServerBusy(Exception exc)
        {
            string strCode    = AzureStorageUtils.ExtractRestErrorCode(exc);
            bool   serverBusy = StorageErrorCodeStrings.ServerBusy.Equals(strCode);

            if (serverBusy)
            {
                numServerBusy.Increment();
            }
            return(serverBusy);
        }