Why Kaminario changed its name to Silk

Four of the most important domesticated silk moths. Top to bottom: Bombyx mori, Hyalophora cecropia, Antheraea pernyi, Samia cynthia. From Meyers Konversations-Lexikon (1885–1892)

Silk is the new name for Kaminario, an on-premises all-flash array startup, that has transformed itself over the last three years into a cloud block storage software company.

Derek Swanson.

Blocks & Files took the opportunity to interview Derek Swanson, Silk CTO, about the company’s transition.

Blocks & Files: Why did Kaminario change its name to Silk?

Swanson: Lots of reasons. Flash and the public cloud are revolutions. … DevOps and the public cloud are forming a new paradigm … More and more enterprises are looking at putting storage in the cloud. Everyone wants to be cloudy, with a legacy footprint. We wanted to acknowledge what’s going on as we are now a cutting edge cloud storage company and not just a legacy, on-premises storage supplier.

Also we’re not a startup anymore. We have a 10-year old software stack that’s been fully ported to the public cloud. It runs with a consistent 300-400 microsecs latency and it’s not using a caching engine. … That contrasts with NetApp and its 10 to 30 millisecs performance in the cloud. … Everything is done in DRAM. … The user experience should be the same on-premises and in the public cloud.

We do all our development on GCP and have done for many years now. Our GCP deployment happened in August 2019. Now we have AWS as well with Azure following in the next few months.

Our controllers are active:active and storage performance scales by adding another compute engine.

Blocks & Files: What about high-availability in the public cloud?

Swanson: Tier one apps running in the public cloud need 100 per cent availability across zones and regions. We do snapshots but we need synchronous writes to multiple zones and regions. That requires write-many snapshots and synchronous replication. We have a robust solution coming later this year.

Blocks & Files: Does VisionOS have predictive analytics? What do they do?

Swanson: VisionOS sends telemetry to Clarity in GCP and we do predictive analytics for performance, capacity, hardware and software failures. We push out patches and firmware upgrades. A minor hardware event pattern can help predict a failure. We initiate pro-active support tickets and up to 92 per cent of all tickets are initiated by us, not customers. In fact we tell the customers.

Blocks & Files: Does Silk think there is a need for a unified file and object storage resource?

We provide a dedicated block store and frontend it with a unified file/object head today. For us to develop a unified file and object offering would be cost-prohibitive. We use other people’s front ends; Ceph, Gluster and Windows Storage Server, for example.

Blocks & Files: Will all storage suppliers have to go to a homogenous, unified on-premises and public cloud offering like Kaminario?

Swanson: The problem is that the big boys sell hardware. Nutanix took a huge hit by exiting the hardware business. The big storage guys couldn’t do it; there would be too big a revenue hit. Co-locating hardware in the public cloud is a short-term fix.

Blocks & Files: What do you think of Pure Storage’s Cloud Block Store public cloud implementation?

Swanson: It’s not a scalable architecture, using active:passive controllers. To provide scalable performance you must have dedicated processing power and memory. 

Pure uses NVRAM as a write cache with NVMe SSDs to commit writes. It’s very fast but it’s not DRAM – and you can’t do it in the cloud. Pure’s storage performance is slower in the cloud than what they get on-premises. It’s a limitation of their architecture. Fixing this would need a rewrite of its Purity OS.

Blocks & Files: How is Kaminario’s move to the hybrid, multi-cloud doing?

Swanson: Customers like it, particularly the on-premises migration element. We’re in a lot of proof-of-values (concepts). A surprising number of cloud-native customers are finding their public cloud storage performance is limited. They have no shared storage and can only get more performance by buying excess compute and networking in the cloud, meaning extra costs.

So we now have interest from cloud customers and Google as we solve storage performance problems in the cloud. Customers don’t need to rewrite their apps. We are partnering and co-selling with Google and hope to do the same with AWS.


The metamorphosis into Silk has taken Kaminario two and half years. In January 2018, the company made its Vision array OS and Clarity analytics software available on a pay-as-you-go basis to cloud service providers. It exited the hardware business at the same time, supplying its software to run on certified hardware built by Tech Data. This hardware and Kaminario’s software became available on subscription in June 2019.

Kaminario started talking about a single storage data plane spanning multiple clouds at the end of last year. And in April, the company announced the Vision OS roadmap, with porting to AWS, Azure and the Google Cloud Platform (GCP).

Google is becoming an important partner. If Swanson is right about Silk’s scalable and consistent performance advantage in the cloud then Silk could grow at the expense of all-flash array vendors, such as NetApp and Pure, with cloudy ambitions.