Case 3:17-cv-05659-WHA Document 154-10 Filed 07/12/18 Page 1 of 2
`Case 3:17-cv-05659-WHA Document 154-10 Filed 07/12/18 Page 1 of 2
`
`
`
`
`
`EXHIBIT 9
`EXHIBIT 9
`
`
`
`
`
`
`
`
`
`
`
`
`
`

`

`Case 3:17-cv-05659-WHA Document 154-10 Filed 07/12/18 Page 2 of 2
`Case 3:17-cv-05659-WHA Document 154-10 Filed 07/12/18 Page 2 of 2
`
`Amazon DynamoDB Developer Guide
`Item Sizes and Capacity Unit Consumption
`
`Item Sizes and Capacity Unit Consumption
`
`Topics
`
`« Capacity Unit Consumption for Reads (p. 297)
`
`« Capacity Unit Consumption for Writes (p. 298)
`
`Before you choose read and write capacity settings for your table, you should first understand your data
`and how your application will access it. These inputs can help you determine your table's overall storage
`and throughput needs, and how much throughput capacity your application will require. DynamoDB
`tables are schemaless, except for the primary key, so the items in a table can all have different attributes,
`sizes, and data types.
`
`The total size of an iter is the sum of the lengths ofits attribute names and values. You can use the
`following guidelines to estimate attribute sizes:
`
`¢ Strings are Unicode with UTF-8 binary encoding. The size of a string is (length of attribute name) +
`(number of UTF-8-encoded bytes).
`
`« Numbersare variable length, with up to 38 significant digits. Leading and trailing zeroes are trimmed.
`The size of a number is approximately (length of attribute name) + (1 byte per two significant digits) +
`(7 byte).
`
`« Abinary value must be encoded in base64 format before it can be sent to DynamoDB, but the value's
`raw byte length is used for calculating size. The size of a binary attribute is (length of attribute name) +
`(numberof raw bytes).
`
`¢ The size of a null attribute or a Boolean attribute is (length of attribute name) + (7 byte).
`
`« An attribute of type List or Map requires 3 bytes of overhead, regardless of its contents. The size of
`a List or Map is (length of attribute name) + sum (size of nested elements) + (3 bytes) . The size of an
`empty List or Map is (length of attribute name) + (3 bytes).
`
`Note
`We recommend that you choose shorter attribute names rather than Long ones. This will help
`you optimize capacity unit consumption and reduce the amount of storage required for your
`data.
`
`
`Capacity Unit Consumption for Reads
`
`
`The following describes how DynamoDB read operations consume read capacity units:
`
`* GetItem—reads a single item from a table. To determine the number of capacity units Getltem will
`consume, take the item size and round it up to the next 4 KB boundary.If you specified a strongly
`consistent read, this is the number of capacity units required. For an eventually consistent read (the
`default), take this number and divide it by two.
`
`For example, if you read an item that is 3.5 KB, DynamoDB rounds the item size to 4 KB. If you read an
`item of 10 KB, DynamoDB rounds the item size to 12 KB.
`
`* BatchGetItem—reads up to 100 items, from one or more tables. DynamoDB processeseach item
`in the batch as an individual Get Ltem request, so DynamoDB first rounds up the size of each item to
`the next 4 KB boundary, and then calculates the total size. The result is not necessarily the same as
`the total size of all the items. For example, if BatchGetItem reads a 1.5 KB item and a 6.5 KBitem,
`DynamoDB will calculate the size as 12 KB (4 KB + 8 KB), not 8 KB (1.5 KB + 6.5 KB).
`
`* Query—reads multiple items that have the same partition key value. All of the items returned are
`treated as a single read operation, where DynamoDB computesthe total size of all items and then
`rounds up to the next 4 KB boundary. For example, suppose your query returns 10 items whose
`
`API Version 2012-08-10
`297
`
`FINJAN-JN 304280
`
`