将40/50记录插入Azure表存储有时会花费30秒以上，因此抛出超时异常

Question

我有一个长期运行的应用程序，任务是每2/3秒插入数据。大多数情况下，它运行良好。但是有时候我会超时。每当它插入约50条记录时，我都会检查一次。我检查了更多的负载，例如超过2000行。它完美地工作。一天中只有几次会引发超时异常。

来源：Microsoft.WindowsAzure.StorageTargetSite：T EndExecuteAsyncTStackTrace：在Microsoft.WindowsAzure.Storage.Core.Executor.Executor.EndExecuteAsync [T]（IAsyncResult结果） 在Microsoft.WindowsAzure.Storage.Core.Util.AsyncExtensions。<> c__DisplayClass2`1.b__0（IAsyncResult ar）---从之前引发异常的位置开始的堆栈结束跟踪--- 在System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw（） 在System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification（任务任务） 在System.Runtime.CompilerServices.TaskAwaiter.GetResult（） 在smi.Server.Shared.VehicleHistoryLibrary.ATVehicleHistoryContext.d__4.MoveNext（）

这是我的代码

ThreadPool.SetMinThreads(1024, 256);
ServicePointManager.DefaultConnectionLimit = 256;
ServicePointManager.UseNagleAlgorithm = false;
ServicePointManager.Expect100Continue = false;

var tableEntityGroups = histories.Select(h => new TrackHistoryTableEntity(h)).GroupBy(e => e.PartitionKey).ToDictionary(g => g.Key, g => g.ToList());
            List<Task> tasks = new List<Task>();
            foreach (var kvp in tableEntityGroups)
            {
                //Merge Track history records with the same FixTaken second into one, taking the average 
                var mergedHistories = kvp.Value.GroupBy(v => v.RowKey).Select(g => new TrackHistoryTableEntity()
                {
                    PartitionKey = g.First().PartitionKey,
                    RowKey = g.First().RowKey,
                    A = g.Select(v => v.A).Average(),
                    N = g.Select(v => v.N).Average(),
                    V = g.Select(v => v.V).Average(),
                    B = g.Select(v => v.B).Average(),
                    D = g.Select(v => v.D).Sum()
                });
                TableBatchOperation batchOperation = new TableBatchOperation();
                foreach (var v in mergedHistories)
                {
                    batchOperation.Add(TableOperation.InsertOrReplace(v));
                    if (batchOperation.Count >= 100)
                    {
                        tasks.Add(TrackHistoryTable.ExecuteBatchAsync(batchOperation));
                        batchOperation = new TableBatchOperation();
                    }
                }
                if (batchOperation.Count > 0)
                {
                    tasks.Add(TrackHistoryTable.ExecuteBatchAsync(batchOperation));
                }

                var splitKey = kvp.Value[0].PartitionKey.Split('_');
                tasks.Add(TrackHistoryTracksTable.ExecuteAsync(TableOperation.InsertOrReplace(new TableEntity(splitKey[0], Int32.Parse(splitKey[1]).ToString()))));

                if (trackPartitionUpdates)
                    tasks.Add(TrackHistoryPartitionUpdatesTable.ExecuteAsync(TableOperation.InsertOrReplace(new TableEntity(TrackHistoryTableEntity.GetHourTimestamp(DateTime.UtcNow).ToString(), kvp.Value[0].PartitionKey))));
            }
            await Task.WhenAll(tasks.ToArray());

Answer 1

这里有两个注意事项：

1. [[[CAUTION] 最大处理的时间[的SLA为30秒，而不是单个实体操作的2秒。有关更多详细信息，请访问https://azure.microsoft.com/en-us/support/legal/sla/storage/v1_5/。
2. [最佳实践]
实施重试政策（例如，最好是指数重试批处理用例并考虑您的] SLA）。 https://docs.microsoft.com/en-us/azure/architecture/best-practices/retry-service-specific#azure-storage上的更多详细信息。希望有帮助！