One of the challenges of offering a unique product is that sometimes it can be difficult for outsiders to classify it with other solutions in the market. So we see, from time to time, published articles that either put the K2 in the wrong bucket or don’t describe the K2’s capabilities completely.
Such is the case with a recent blog by Ruben Spruijt that discusses different types of SSD solutions including hybrid file systems, Flash-only arrays and server-side Flash. While it is true that the Kaminario K2 offers a single enclosure for blade servers connected with Flash, it is not accurate to include the K2 in the server-side Flash category. Spruijt does not specifically call out Kaminario as a server-side SSD solution, but it appears that way from the mention.
Kaminario Makes All Solid-State SAN Storage — Absent a category for all solid-state SAN storage to include Flash and DRAM, Spruijt should have mentioned the K2 in his Flash-only array discussion. As my colleague Eyal Markovich said, “server-based PCIe cards are, by nature, local to the server, so they cannot serve as part of a server cluster. That means they’re out as an SSD solution for running Oracle Real Application Clusters (RAC) or an SQL Server instance as part of a Microsoft Cluster. Since the K2 is SAN-based, it fully supports these clustering configurations.” This is just one example why readers should understand that the K2 is a solid-state SAN storage array versus a server-side SSD solution.
Beyond Classification Issues — Beyond label issues, Spruijt has some good information about the pros and cons of various SSD solution types. I think commentary on specific applications and how they fit with different SSD solutions would have made the article more useful.
Flash-Only Discussion—I agree with him that “Flash-only arrays have some advantages over Flash-cached/tiered arrays, they are generally designed from the ground up to take full advantage of the speed that SSD drives can provide and have advanced wear-leveling and management capabilities.”
Spriijt says that HDDs are cheaper than SSDs for capacity. However, it is not hard to see that SSD prices are falling. When you combine that with the fact that SSDs are a better value per IOPS, the SSD business case gets even more compelling.
It is nice that he calls out high availability in the Flash-only section because it often gets overlooked in SSD discussions. “Only recently players in this segment have started to offer HA within the array as an option, without it, this can’t be used to support business critical applications without organizing fail-over/redundancy at higher (application/OS) levels.” We introduced DataProtect capabilities last February to cement HA as a strong differentiator for the K2.
What’s Next —Finally, Spruijt’s article talks about technologies that may eventually overtake Flash such as Phase-change Memory (PRAM), Ferroelectric RAM (FeRAM) and Magnetoresistive RAM (MRAM). No one really knows what technologies will pan out and when, but one good thing about being a software company that uses off-the-shelf components is that it will help us adapt to tech evolutions quickly. That could mean combining memory technologies into a single array like we have done for Flash and DRAM or integrating other technologies that emerge.
If you are still learning about SSD-flavored storage solutions, check out Spruijt article. Just know that Kaminario is all solid-state SAN storage.
Tags: application performance, database, Database Performance, DataProtect, Disk latency, Flash, Flash SSD, high availability, I/O bottlenecks, IOPS, K2, Kaminario, Storage Performance, writes
