Tuesday, August 23, 2016

[Links of the day] 23/08/2016 : Adapting In memory database architecture for Storage class memory and Datacenter network congestion management

  • The implication of Storage Class Memory for In memory database architecture : 
    • SOFORT : The authors propose to modify traditional In memory database architecture in order to optimise its operation for upcoming storage class memory hardware. The idea is quite simple, get rid of the log mechanism and persist all data to NVM except for the index which needs to be maintained in RAM for performance requirement. SCM allow to drastically eliminate a lot of boiler plate architecture functionality by delivering fast byte addressable persistent storage. However, now the developers needs to be aware of the transnational model imposed by this new class of persistent memories. [Slides]
    • Instant Recovery for Main-Memory Databases : This paper build on top of SOFORT and looks at leveraging NVDIMM or SCM for speeding up crash recovery features. The idea is not only speed up the normal operation but also eliminate the recovery cost in case of application crash [Slides]
    • Note that both these paper have an author working for SAP, so my guess that we will start to see new dedicated feature in SAP Hana for supporting SCM.
  • Flowtune : It seems that we are going to see slowly a return of the ATM model in data-center for networking fabric. In this paper the author propose to combine a form of MPLS system with a centralized allocator for resources management and congestion avoidance.  Basically the system identify connection ( called flowlet )  establishment  and end . Using the existing and past information it derive an optimal path and resources allocation minimizing interference and congestion over the lifetime of the flowlet. Looks like SDN is finally enabling a simplified and more robust ATM model within and probably across data-centers.