Most of my peers know that I’m not one to dig deep into many nuances of storage. I consider storage to be a necessary evil in which there will always be a surly storage administrator to give me the runaround on why a virtual workload isn’t performing up to expectations. However, in an effort to become a more well rounded technologist, I have decided to make my first Tech Field Day 14 preview post specifically about a storage company. During the event, which will happen on May 11th and 12th of 2017 (in Boston), we will hear much more about a storage company that appears to be doing things differently than most of their storage brethren.
I’ll reference, again, that I’m not much of a storage expert. In fact, in the right moment, you might be able to sneak by me made up storage terms (say, triple crunch parity). That being said, one of the things about Datrium’s architecture that stood out to me was the disaggregated approach of their architecture. While I may have seen various attempts at this approach, I’ve not seen it to the level Datrium has taken it to.
Datrium’s storage solution, called DVX Rackscale, is a combination of a back-end storage array and a software element that is installed onto a VMware-based host. As part of the requirements of that VMware-based host, there needs to be some amount (between one and ten disks) of flash storage installed into that host. This local flash storage is used to store read-only, cached copies of more active data. Connected to each host, via 10Gb Ethernet, is a single back-end disk array that contains the high-capacity, slower-performance disks in which the master copy of all data resides. This back-end array is also the location where writes occur. One of the interesting facets of this architecture is that it claims the more hosts you add to this solution, the faster performing the overall system becomes. Datrium’s data sheets indicate performance estimates with 4K workloads to be roughly 100k IOPS per host, with a potential to drive nearly 3,000,000 IOPS in a maximum configuration. Those numbers for 32K workloads are reduced (as expected) but still drive some impressive numbers (40k IOPs per host; 1.2 million IOPS across a maximum configuration).
There are some maximums that need to be dealt with in the architecture. For instance, you can only connect 32 VMware ESXi hosts to a single back-end storage array. Also, it appears that the back-end array is non-upgradable (the system has 12 – 4TB 7200rpm HDDs), meaning the current capacity you can be working with will vary between 60TB and 180TB. Like many things storage related, this number is going to vary wildly based on the reduction techniques and their abilities within the system (Datrium expects between 2x and 6x reduction ratios, based of their datasheets).
An Industry First? – Blanket Encryption
External to the architecture of DVX are some very unique features that are not found on many other storage devices. One such feature is called Blanket Encryption. This feature, a completely software-based solution, manages to overcome some of the tradeoffs we see in current solutions. Many hardware solutions only go as far as to offer at rest data encryption. Combine in the penalties to reduction capabilities by encryption at the source and you’ve got a lot of wasted resources in trying to provide minimal protection capabilities.
Datrium’s DVX solution claims to be able to provide you the best of all worlds. As they are dependent upon their own software in the hypervisor stack, they are capable of doing better source protection in the VMware host RAM and local flash disks that do not cause the same penalties seen by just the hypervisor itself. The very same software is also capable of performing in-flight encryption from the host to the storage array. According to Datrium’s datasheets, the data is first fingerprinted, then compressed, and finally encrypted while it’s being created in the ESXi host RAM. Then the data is transmitted to the storage array (as ciphertext). All the while, this is being done using some of Intel’s advanced instruction sets to help offload the performance hit to do all of these operations.
My Non-Storage Enthusiast Take
There is plenty more to look at, when it comes to Datrium’s DVX solution. Recently added to the portfolio is a very unique replication system and snapshot catalog system. This replication system is extensive enough to almost justify an entire write up to discuss it’s intricate details. Combine this replication system with plans to work toward’s public cloud replication (while ensuring the public cloud data is able to take advantage of the same on-premises blanket encryption!) and we have a lot more to talk about with Datrium. Personally, I’m excited to hear and see more about blanket encryption. Also, it seems that Datrium has decided to get into the compute market with their own Intel-based servers, preconfigured for VMware ESXi and the DVX software. It’ll be interesting to ask why the need to jump into that overly saturated hardware market.