Do you see a folder in your bucket named “db”? All the data files will be there.
In the HSDS schema, folders and domain names are stored by their path (e.g. /shared/mydata.h5 will be stored in s3://bucketname/shared/mydata.h5/domain.json). Inside domain.json there will be a key for the root group id which points to an object under the db/ path.
The rational for this approach is that it makes it easy to move or rename domain names without having to move each data object.
If you are curious, this doc: https://github.com/HDFGroup/hsds/blob/master/docs/design/obj_store_schema/obj_store_schema_v2.md, describes the storage model in some detail.
BTW, if you run: hsinfo <domain_name>, you’ll get information about the number of json objects, data objects, storage size, etc. for that domain. E.g.:
$ hsinfo /shared/bioconductor/tenx_full.h5
last modified: 2021-06-19 22:22:58
last scan: 2021-06-19 22:19:22
md5 sum: 4fafc30a05df174ca5cc8f05e4c6e659
num objects: 2
num chunks: 105273