[anyoneamous]

My impression is that the ambiguity gives them freedom to implement in different ways across different regions and over time.

The original Glacier was very clearly tape, but given the instant retrieval capabilities the newer S3-Glacier tiers are most likely just low-margin HDDs, maybe with some dynamic powering on and off of drives/servers.

[danpalmer]

I’m sure it’s a mix. Back when it launched there were a number of rumours about it being Blu-Ray based. They had similar capacity for the space used compared to tapes, were considered very physically stable storage mediums, but had long access time as they would need to be physically moved, like tape, explaining the retrieval times.

[anyoneamous]

I don't buy the Blu-ray thing largely because of price, but also because Amazon is quite a conservative company and tape is the more obvious choice.

[bombcar]

Glacier is just run on S3 with some sleep statements added.

[aitchnyu]

The perceived value of results is higher if it takes a longer time to load, users feel the computer is hard at work. If its true for flight searches, its true for backup systems.

[bombcar]

Reminds me of the automated phone systems that play random keystrokes while telling you they’re looking up your info - people don’t trust it if they come back instantly, I guess.

[jdwithit]

I am going to choose to believe this

[lytfyre]

I recall at launch just about the only implementation detail that _was_ publicly given was that it did not involve tape. That's going to be difficult to dig up a cite on years later.

No idea how it's evolved over the years, so for all I know it's tape based these days.