[agwa]

As someone who operates a PostgreSQL database containing 27 billion SSL certificates, each 1-2kb each, with a bunch of secondary indexes that get inserted in random order, I find it pretty incredible that people see the need to optimize their session database. At what scale does the size of the session database actually matter?

Those stateless tokens may be "unforgeable", but they are replayable, and if you're not mindful of that you can have security vulnerabilities.

[mewpmewp2]

I think one meaningful case is when you have services in very different locations and you would rather than having to make a request to a session store in a single location, replicate the data to each location for better latency, so in this case a revocation list.

[hparadiz]

You should do some basic optimizations. Fixed length table and indexes on the unique string for fast lookups. I also like to do a rolling delete for old sessions after 30 days unless mobile session that is logged in. Those get to live forever.

[agwa]

Fair enough, but those optimizations are basically free. People think stateless tokens are free but they really are not.

[hparadiz]

The cost of the stateless token is basically the CPU usage for signing the message and checking the signature with the public key on the client. Example: Google Compute Instance asks metadata server for OIDC token (which is a JWT). The metadata server respond with the token that basically says "here's the machine service account, here's the machines ID, this token is proof that I am service account abc123 and it's valid for 20 seconds". This is one of the most common uses of JWTs in enterprise. You don't store them. They actually are free.

Lots of web devs get tricked into using them as primary session tokens and it's a huge anti pattern. I see it all the time and people get aggressive about it.

[agwa]

The cost is the vigilance required to use them safely. It's not just compute/storage costs.

[hparadiz]

I didn't downvote you. You're absolutely right. Implementation of anything is work.