Caching subsys: db, filesystem, do we even need something?

[goodboy]

Recently there's been some discussion on a caching layer for stuff like:

• MktInfo data that will land in #489
• general provider symbology (schemas) and dynamic update of venue instrument offerings
• accounting state which is currently entirely managed in TOML files on the local filesystem of the brokerd actor.
• aggregated multi-trader order dialog states

maybe more?

---

FOSS systems worth checking out in this space:

• we already are using elasticsearch for some option OI tracking
• rocksdb: https://rocksdb.org/ (from META)
• repo: https://github.com/facebook/rocksdb/
• pyclient: https://github.com/stephan-hof/pyrocksdb