Cost really depends on your workflow, your durability needs, prefetch aggression (how quickly you need all the data locally), and how aggressively you cache. The storage is what it is, and it's cheap. The variation comes in transaction counts.

If you evict the cache on every read/write, then all reads and writes do S3 GET. PUTs are 10-100x more expensive than GETs usually. Check the benchmark/README.md for GET counts, but it's usually 5-50 per cold read (with interior B-tree pages on disk).

S3 GETs are $0.0004/1000, S3 Express is $0.00003. So 10 queries per minute all day long averaging 20 GET operations, with full eviction on each request, would be 20*10*$0.0004*60*24/1000*30 = $3.45 per month. With S3 Express One Zone that's $0.26/mo. Both plus storage costs, which would probably be lower.

On Wasabi, that would be just the cost of storage (but they have minimum 1TB requirements at $6.99/mo).

If you checkpoint after every write and write 10 times per minute, each write hitting e.g. 5 page groups (S3 objects) plus the manifest file, the analysis looks like: 6*10*$0.005*60*24/1000*30=$12.96. Again that's worst case for the benchmark 1.5GB database. On S3 Express that' $2.92.

Point is - it's not too bad, and that's kind of worst-case scenario where you evict on every request every 6 seconds which isn't really realistic. If you evict the cache hourly, that cost goes is 1/600th - less than a $0.01 per month.

Summary: use S3 Express One Zone, don't evict the cache too often, checkpoint to S3 once a minute (turbolite lets you checkpoint either locally (disk-durability) or locally+S3 separately), and you're running a decent workload for pennies every month.

[Apologies for the spreadsheet math in plaintext]

im also curious. GCS also charges per GET request