The SNIA Cloud Storage Initiative recently hosted a live webcast â€œContainers and Persistent Memory.â€ Where my colleagues and I discussed persistent storage for containers, persistent memory for containers, infrastructure software changes for persistent memory-based containers, and what SNIA is doing to advance persistent memory. If you missed the live event, itâ€™s now available on-demand. You can also download a PDF of the webcast slides.
As promised, we are providing answers to the questions we received during the live event.
Q. How is” Enterprise Server SAN” different from “Traditional” Server SAN?
A. Traditional Server SAN refers to individual servers connected to a dedicated, separate SAN storage solution (e.g. EMC VNX, NetApp FAS, etc.); whereas, Enterprise Server SAN refers to the use of direct-attached-storage that is then aggregated across multiple connected servers to create a â€œvirtual SANâ€ that is not a separate storage solution, but rather benefits from utilizing the existing capacity contained within the application servers, but in a virtualized, shared pool to improve overall efficiency.
Q. Are there any performance studies done with Containers using Tier 1 apps/Business critical?
A. There have been performance characterizations done on Tier 1, Business Critical applications such as Oracle, MySQL and others. However, this would be vendor specific and the user would have to contact and work with each storage vendor to better understand their specific performance capabilities.
Q. Even though Linux and Microsoft support NVDIMM natively, does the MB/BIOS still need to have support?
A. Yes, the MB needs to have the BIOS enabled to recognize NVDIMMs and it needs the ADR signal wired from the Intel CPU to the DIMMs sockets. The motherboard needs to follow the JEDEC standard for NVDIMMs.
Q. If someone unplugs NVDIMM-N and moves it to another server… what will happen?
A. If the system crashed due to a power loss the data in the NVDIMM will be saved. When it is plugged into another NVDIMM-enabled server the BIOS will check if there is saved data in the NVDIMM and restore that data to DRAM before the system continues to boot.
Q. Are traditional storage products able to support containerized applications?
A. Yes, assuming that they support container orchestration engines such as Docker Swarm or Kubernetes through a â€œcontainer volume plugin.â€ However, to the extent that they support containerized applications, it is very specific vendor-to-vendor and there are also a number of new storage products that have been developed exclusively to support containerized applications (e.g. Veritas, Portworx, Robin Systems).
Q. How do the storage requirements for containers compare or differ from those of virtual machines?
A. Actually, â€œproduction storage requirementsâ€ are very similarâ€”albeit almost equivalentâ€”between containerized applications and applications running within virtual machines; the main difference being that due to the scalability potential of containers, these requirements are often exacerbated. Some of these requirements common to both include: data persistence, data recovery, data performance and data security.