Redwood Storage Engine documentation for 7.1 is missing

@johscheuer Thanks for your suggestion. So I wonder what storage engine string should be added here?
I just found the following code:

const (
// StorageEngineSSD defines the storage engine ssd.
StorageEngineSSD StorageEngine = “ssd”
// StorageEngineSSD2 defines the storage engine ssd-2.
StorageEngineSSD2 StorageEngine = “ssd-2”
// StorageEngineMemory defines the storage engine memory.
StorageEngineMemory StorageEngine = “memory”
// StorageEngineMemory2 defines the storage engine memory-2.
StorageEngineMemory2 StorageEngine = “memory-2”
// StorageEngineRocksDbExperimental defines the storage engine ssd-rocksdb-experimental.
StorageEngineRocksDbExperimental StorageEngine = “ssd-rocksdb-experimental”
// StorageEngineRocksDbV1 defines the storage engine ssd-rocksdb-v1.
StorageEngineRocksDbV1 StorageEngine = “ssd-rocksdb-v1”
// StorageEngineShardedRocksDB defines the storage engine ssd-sharded-rocksdb.
StorageEngineShardedRocksDB StorageEngine = “ssd-sharded-rocksdb”
)

What redwood engine string like? Would you provide an example?
And after adding the storage engine string we need also add some logic to handle it, right? Is there any example?

Now we have tested fdb7.1(default storage engine) against fdb6.2, and found when the data size is 100000 rows, 7.1 is better than 6.2, but when the data size is 500000 rows, 6.2 is much better than 7.1, is it as designed? You can check the details here (Is there any performance report for fdb7.1 vs fdb6.2? - #2 by liyyue) , thanks!