Briefing Note

George Crump, Senior Analyst

Scality is not a client of Storage Switzerland

When we speak of cloud storage as an architecture we most often mean some sort of a scale out or grid storage architecture made up of individual nodes. As you add nodes you add storage and processing capability. The idea is to offer limitless scale without decreasing performance or increasing management requirements. In addition many, if not most, of these solutions run on industry standard hardware which allows this scale and management ease to be realized at very competitive price points. 

This architecture can be deployed by a service provider or even a private data center so they can benefit from that same cloud architecture that the larger cloud storage providers are leveraging to keep costs and management time down. Thus far most deployments have been used as a secondary storage tier to store archives or backup data.

The image of scale out storage is often a linear graph where nodes are added to the end of the chain. The Scality solution is similar to the above except they want you to think in a 360 circle instead of a straight line. The Scality RING is a grid storage architecture that leverages this logical ring to be able to improve performance and reliability. Through math calculations it can more quickly direct data requests because of the nodes position in the ring. By improving performance Scality believes their solution can appeal to more primary storage use cases while still maintaining the cost advantages of traditional cloud storage solutions.

Scality’s background is working with large email service providers. As they worked with these providers the limitations of traditional storage architectures to support the high IOPS, high scalability and high price competitiveness of the email data set began to make growth increasingly more expensive. Public email providers need to be able to provide a unique balance of price and performance. From this experience Scality decided to focus its efforts on creating a storage solution to address these challenges.

As mentioned above the Scality RING leverages the cloud storage architecture but is focused on the primary tier. It is also an object based storage system which is becoming increasingly common in cloud storage architectures and is ideal for high object/file count environments. Scality is a software only storage solution that loads on standard X86 servers. The typical node is a 2U server loaded with drives. Each server that the software is loaded onto becomes a member of the ring. Each processing core within the server is a node within the cluster. This makes it easy to build a fairly high node count with a small number of physical machines.

Files or data are stored as objects within the Scality RING. As with most object based systems you do not typically access the storage with the typical file system mount most of the time you are using a REST API set or some other form of direct communication. As mentioned above Scality’s background is in the email space so it is not surprising that they built direct access to their storage from Zimbra, an email solution common within the email service provider community.

Objects (files, email messages, etc...) are written intact on a single node. As those objects are stored within the ring, the objects are replicated to another node in the ring to make sure that redundant data is not stored in the node next to node that had the original copy of the object. The Scality RING uses a mathematical formula to understand where all the object replica’s are. There is no look up that needs to occur which helps performance as the environment scales.

Why object storage in the email provider and other markets? In most cases these systems will run into file system limitations (running out of inode space) long before they run out of capacity. In this environment the system administrators are often balancing email data across many volume and storage system heads. Object storage gets around these problems by eliminating the need for file system metadata like inode tables. The storage administrator now has to deal with a single storage management object which eases management significantly.

Storage Swiss Take

The Scality RING is an interesting approach to solving the storage challenges of high object count environments, with email storage infrastructures being the perfect example of the problem that the product can solve. These environments not only have the complexity of the storage management challenges caused by high object counts, they also have the added pressure of being in a market where price competitiveness as well as reliability are keys to survival. It is hard to deliver the three requirements of performance, competitiveness and reliability in a single platform. By leveraging its RING, Scality may be able to do just that.