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- Data model. RAMCloud currently supports a very simple data model (key-value store); we would like to see if we can provide higher-level features such as secondary indexes and multi-object transactions while without sacrificing the scalability or performance of the system.
- Consistency: we believe that RAMCloud can provide strong consistency (serializabilitylinearizability) without sacrificing performance, but there are several interesting problems to solve in order to achieve that.
- Cluster management: what are the right mechanisms and policies for reorganizing RAMCloud data in response to changes in the amount of data and the access patterns?
- Network protocols: we don't think that TCP is the right protocol to provide highest performance within a datacenter, so there is an interesting research project to investigate what is the ideal protocol.
- Multi-tenancy: how to support multiple independent, perhaps hostile, applications sharing the same RAMCloud storage system within a large datacenter? This introduces issues related to access control and also potentially issues of performance isolation.
- Multiple datacenters: our current design for RAMCloud focuses on a single datacenter, but some applications will require redundancy across datacenters in order to protect against datacenter failures. An interesting question is whether we can provide that level of redundancy without dramatically impacting the performance of the system.
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