Does not allow to provide custom DB (Level DB) Options

[moniya12]

cosmos-sdk/server/start.go

Line 269 in ccc5245

node.DefaultDBProvider,

As Node is initialized with DefaultDBProvider (Tendermint), applications are not able to expose custom DB Options. Tendermint DB supports DB with custom options - https://github.com/tendermint/tm-db/blob/358078c8bed0eb5113fef6bea376d1a620757308/goleveldb/db.go#L24 but application are not able to use it as CosmosSDK only allows default db provider.

Enabling custom LevelDB (or RocksDB) options would allow validators and app developer provide aggressive pruning options. Without aggressive pruning we are not able to reclaim space for months (when pruning is enabled).

We have thread over here explaining how default Level DB compactions does not reclaim space for months - https://twitter.com/valnodes/status/1435465250803945472

[JayT106]

crypto-org-chain/cronos#387

[tac0turtle]

@moniya12 which setting would you want to add?

[tac0turtle]

exposing this to the application makes sense to me. @alexanderbez thoughts on including this in the design of store v2?

[yihuang]

We did this with rocksdb by adding an API NewDBWithRawDB, so user can open the db in whatever way they want, we just need to provide similar APIs for all supporting backends I think.
Then in server start command, allow user to supply a custom db opener callback.

[alexanderbez]

Yeah we'll do this in the store V2 design, although we'll stick with RocksDB as the default.