Migration overview

The IBM® Cloudant® for IBM Cloud® database-as-a-service offering is a JSON document store that runs on multi-tenant clusters. The service is available with a choice of geographical locations with predictable costs, scalability, and a service-level agreement (SLA).

You can migrate to an IBM Cloudant Lite or Standard plan instance on IBM Cloud from one of the following plans:

Table 1. IBM Cloudant migration paths
Plan	Description
IBM Cloudant Enterprise	Dedicated, single-tenant clusters
Apache CouchDB	The self-hosted, open source database on which IBM Cloudant is based.

Benefits of the IBM Cloudant Lite and Standard plans

With the Standard plan, you can reserve throughput capacity for your database service, that is, to specify how much throughput your application's database is going to need to handle demand. The Standard plan also charges for the amount of storage you use. Capacity is measured with the following metrics:

Table 2. Capacity metrics
Metric	Description
Reads per second	The rate when simple document fetches are performed, for example, retrieving a document by its `_id`, or querying against a partitioned database that uses a partition key.
Writes per second	The rate when data is written to the database. API calls dealing with document creation, update, or deletion count as "writes".
Global Queries per second	The rate when the database is queried by global indices, typically by accessing the `_find` endpoint, secondary MapReduce, or search indices.
Storage	The amount of disk space occupied by your JSON data, attachments, and secondary indices.

As an example, the Lite plan offers 20 reads per second, 10 writes per second, 5 global queries per second, and 1 GB of storage for free. This plan is ideal when you're evaluating the product and during product development. When your application goes into QA or production, switch to the Standard plan to scale the instance. The Standard plan's smallest capacity has 100 reads per second, 50 writes per second, 5 global queries per second, and 20 GB of storage for ~USD$76.65 per month. You can buy extra storage, which is charged by the GB.

By using the slider in the IBM Cloudant Dashboard, you can reserve a smaller or larger capacity for your IBM Cloudant service whenever you need it:

You can increase or decrease your capacity for IBM Cloudant service by using the slider. — Figure 1. Slider

The amount that you can change the throughput capacity is limited to a maximum of 10 units per change with a maximum of one change per hour. Notice the "change limit" point on the slider. Changes downward are unlimited in size, but still subject to the time limit.

You're billed on the highest capacity that is selected in any given hourly window. Your database throughput can scale up to deal with seasonal demands and scale down again for the quiet times. Your monthly bill is always predictable; upgrades are automatic; and your SLA is 99.99%.

If you exceed your quota of reads, writes, and global queries in a given second, the IBM Cloudant API responds with a 429: too many requests HTTP response. Your application might retry the request later. You can use our official libraries to retry such requests with an exponential back off.