Maximum capacity that Dynamodb can scan at a time

Question

AWS describes

a single Scan request can consume (1 MB page size / 4 KB item size) / 2 (eventually consistent reads) = 128 read operations. https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/bp-query-scan.html

128 seems to be the maximum capacity which Scan command can read at a time.

However, when I test, Scan command(eventually consistent, without any filter option) is always returned at 119.5 capacity though there are enough items to read.

Why does this mismatched figure come out?

Answer 1

The key word here is "can". From the documentation, they say "a single Scan request can consume ..."

This is their written limit, which means depending on the item size and other variants, the actual capacity will be different.