The spectrum
Not all data is read equally, so stores offer storage classes that trade price against access speed.
- Hot tiers keep data on fast media, ready in milliseconds, at the highest storage price but lowest read price.
- Cold tiers cost less to store but charge more per read and may add a small access delay.
- Archive tiers are the cheapest to hold but can take minutes to hours to retrieve and charge a retrieval fee.
The hidden costs
The storage price is only half the story. Cold and archive classes add per request retrieval charges and often a minimum storage duration. Deleting an archived object early can cost more than leaving it. Picking a tier means modeling read frequency, not just bytes.
How to choose
- Frequently read working data goes hot.
- Backups read a few times a year go cold.
- Compliance data almost never read goes archive.
Key idea
Storage classes trade storage price against retrieval latency and fees, so the right tier depends on how often you read the object, not just its size.