Storage - Amazon Timestream


Timestream for Live Analytics stores and organizes your time series data to optimize query processing time and to reduce storage costs. It offers data storage tiering and supports two storage tiers: a memory store and a magnetic store. The memory store is optimized for high throughput data writes and fast point-in-time queries. The magnetic store is optimized for lower throughput late-arriving data writes, long term data storage, and fast analytical queries.

Timestream for Live Analytics ensures durability of your data by automatically replicating your memory and magnetic store data across different Availability Zones within a single AWS Region. All of your data is written to disk before acknowledging your write request as complete.

Timestream for Live Analytics enables you to configure retention policies to move data from the memory store to the magnetic store. When the data reaches the configured value, Timestream for Live Analytics automatically moves the data to the magnetic store. You can also set a retention value on the magnetic store. When data expires out of the magnetic store, it is permanently deleted.

For example, consider a scenario where you configure the memory store to hold a week's-worth of data and the magnetic store to hold 1 year's-worth of data. The age of the data is computed using the timestamp associated with the data point. When the data in the memory store becomes a week old it is automatically moved to the magnetic store. It is then retained in the magnetic store for a year. When the data becomes a year old, it is deleted from Timestream for Live Analytics. The retention values of the memory store and the magnetic store cumulatively define the amount of time that your data will be stored in Timestream for Live Analytics. This means that for the above scenario, from the time of data arrival, the data is stored in Timestream for Live Analytics for a total period of 1 year and 1 week.


When you upgrade the retention period of the memory or magnetic store, the retention change takes effect from that point onwards. For example, if the retention period of the memory store was set to 2 hours and then changed to 24 hours by updating the table retention policies, the memory store will be capable of holding 24 hours of data, but will be populated with 24 hours of data 22 hours after this change was made. Timestream for Live Analytics does not retrieve data from the magnetic store to populate the memory store.

To ensure the security of your time series data, your data in Timestream for Live Analytics is always encrypted by default. This applies to data in transit and at rest. Furthermore, Timestream for Live Analytics enables you to use customer managed keys to secure your data in the magnetic store. For more information on customer managed keys, see AWS KMS keys.