amazon-dynamodb - DynamoDB 的一致性模型、CAP、分区恢复等有哪些文档？

Question

我正在考虑使用亚马逊的 DynamoDB。自然地，如果您不想使用高度可用的分布式数据存储，您希望确保您的客户以合理的方式处理中断!

虽然我可以找到描述亚马逊“Dynamo”数据库的文档，但我的理解是“DynamoDB”derives its name from Dynamo, but is not at all related in any other way .

对于 DynamoDB 本身，我能找到的唯一文档是 brief forum post基本上说“重试 500 个错误”。对于大多数其他数据库，可以获得更详细的信息。

我应该在哪里了解有关 DynamoDB 中断处理的更多信息？

Answer 1

虽然 Amazon DynamoDB确实缺乏关于他们对CAP theorem 的选择的详细说明。 (仍然希望 Kyle Kingsbury 最优秀的 Jepsen 系列的 DynamoDB 版本 - Call me maybe: Cassandra 分析受 Dynamo 启发的数据库)，Jeff Walker Code Ranger 对 DynamoDB: Conditional writes vs. the CAP theorem 的回答证实在这方面缺乏明确的信息，但断言我们可以做出一些非常有力的推论。

引用 forum post事实上，也暗示了对可用性的高度重视:

DynamoDB does indeed synchronously replicate across multiple availability zones within the region, and is therefore tolerant to a zone failure. If a zone becomes unavailable, you will still be able to use DynamoDB and the service will persist any successful writes that we have acknowledged (including writes we acknowledged at the time that the availability zone became unavailable).

The customer experience when a complete availability zone is lost ranges from no impact at all to delayed processing times in cases where failure detection and service-side redirection are necessary. The exact effects in the latter case depend on whether the customer uses the service's API directly or connects through one of our SDKs.

除此之外，Werner Vogels 在 Dynamo/DynamoDB 上的帖子最终提供了更多见解:

Amazon's Dynamo - 关于原论文

Amazon DynamoDB – a Fast and Scalable NoSQL Database Service Designed for Internet Scale Applications - 主要介绍性文章包括:

亚马逊 NoSQL 的历史 – Dynamo

亚马逊 Dynamo 的经验教训

DynamoDB 简介 - 这提供了与主题最相关的信息

Durable and Highly Available. Amazon DynamoDB replicates its data over at least 3 different data centers so that the system can continue to operate and serve data even under complex failure scenarios.

Flexible. Amazon DynamoDB is an extremely flexible system that does not force its users into a particular data model or a particular consistency model. DynamoDB tables do not have a fixed schema but instead allow each data item to have any number of attributes, including multi-valued attributes. Developers can optionally use stronger consistency models when accessing the database, trading off some performance and availability for a simpler model. They can also take advantage of the atomic increment/decrement functionality of DynamoDB for counters. [emphasis mine]

DynamoDB One Year Later: Bigger, Better, and 85% Cheaper… - 关于改进

最后，Aditya Dasgupta 关于 Amazon's Dynamo DB 的介绍还分析了其关于 CAP 定理的操作方法。

实用指南

在重试处理的实践指导方面，DynamoDB 团队同时增加了一个关于 Handling Errors 的专门部分。 ，包括 Error Retries and Exponential Backoff .