Amazon DynamoDB | Reserved capacity Flashcards
How long does it take to change the provisioned throughput level of a table?
Reserved capacity
Amazon DynamoDB | Database
In general, decreases in throughput will take anywhere from a few seconds to a few minutes, while increases in throughput will typically take anywhere from a few minutes to a few hours.
We strongly recommend that you do not try and schedule increases in throughput to occur at almost the same time when that extra throughput is needed. We recommend provisioning throughput capacity sufficiently far in advance to ensure that it is there when you need it.
What is Reserved Capacity?
Reserved capacity
Amazon DynamoDB | Database
Reserved Capacity is a billing feature that allows you to obtain discounts on your provisioned throughput capacity in exchange for:
A one-time up-front payment
A commitment to a minimum monthly usage level for the duration of the term of the agreement.
Reserved Capacity applies within a single AWS Region and can be purchased with 1-year or 3-year terms. Every DynamoDB table has provisioned throughput capacity associated with it, whether managed by Auto Scaling or provisioned manually when you create or update a table. This capacity is what determines the read and write throughput rate that your DynamoDB table can achieve. Reserved Capacity is a billing arrangement and has no direct impact on the performance or capacity of your DynamoDB tables. For example, if you buy 100 write capacity units of Reserved Capacity, you have agreed to pay for that much capacity for the duration of the agreement (1 or 3 years) in exchange for discounted pricing.
How do I buy Reserved Capacity?
Reserved capacity
Amazon DynamoDB | Database
Log into the AWS Management Console, go to the DynamoDB console page, and then click on “Reserved Capacity”. This will take you to the “Reserved Capacity Usage” page. Click on “Purchase Reserved Capacity” and this will bring up a form you can fill out to purchase Reserved Capacity. Make sure you have selected the AWS Region in which your Reserved Capacity will be used. After you have finished purchasing Reserved Capacity, you will see purchase you made on the “Reserved Capacity Usage” page.
Can I cancel a Reserved Capacity purchase?
Reserved capacity
Amazon DynamoDB | Database
No, you cannot cancel your Reserved Capacity and the one-time payment is not refundable. You will continue to pay for every hour during your Reserved Capacity term regardless of your usage.
What is the smallest amount of Reserved Capacity that I can buy?
Reserved capacity
Amazon DynamoDB | Database
The smallest Reserved Capacity offering is 100 capacity units (reads or writes).
Are there APIs that I can use to buy Reserved Capacity?
Reserved capacity
Amazon DynamoDB | Database
Not yet. We will provide APIs and add more Reserved Capacity options over time.
Can I move Reserved Capacity from one Region to another?
Reserved capacity
Amazon DynamoDB | Database
No. Reserved Capacity is associated with a single Region.
Can I provision more throughput capacity than my Reserved Capacity?
Reserved capacity
Amazon DynamoDB | Database
Yes. When you purchase Reserved Capacity, you are agreeing to a minimum usage level and you pay a discounted rate for that usage level. If you provision more capacity than that minimum level, you will be charged at standard rates for the additional capacity.
How do I use my Reserved Capacity?
Reserved capacity
Amazon DynamoDB | Database
Reserved Capacity is automatically applied to your bill. For example, if you purchased 100 write capacity units of Reserved Capacity and you have provisioned 300, then your Reserved Capacity purchase will automatically cover the cost of 100 write capacity units and you will pay standard rates for the remaining 200 write capacity units.
What happens if I provision less throughput capacity than my Reserved Capacity?
Reserved capacity
Amazon DynamoDB | Database
A Reserved Capacity purchase is an agreement to pay for a minimum amount of provisioned throughput capacity, for the duration of the term of the agreement, in exchange for discounted pricing. If you use less than your Reserved Capacity, you will still be charged each month for that minimum amount of provisioned throughput capacity.
Can I use my Reserved Capacity for multiple DynamoDB tables?
Reserved capacity
Amazon DynamoDB | Database
Yes. Reserved Capacity is applied to the total provisioned capacity within the Region in which you purchased your Reserved Capacity. For example, if you purchased 5,000 write capacity units of Reserved Capacity, then you can apply that to one table with 5,000 write capacity units, or 100 tables with 50 write capacity units, or 1,000 tables with 5 write capacity units, etc.
