The drop in price for solid state drives continues to fuel the adoption rate of this storage media. While the debate continues about if and when solid state will replace hard drives, it is clear that in the majority of applications, tiering solid state storage with HDDs into a hybrid volume makes economic sense today.
The true cost of storage takes into account both the acquisition costs of hardware as well as ongoing operating costs, with power and cooling accounting for a significant portion of the operating costs. Over a 5 year period, a scale out storage architecture which incorporates tiered hybrid storage saves significant costs over both a pure HDD solution as well as an all flash solution.
Total savings are dependent on the performance and capacity requirements of the system, but tiered hybrid storage shows cost benefits in most cases. For example, the TCO chart above shows the cost benefits of a scale out server based storage implementation with ~ 530 TB of storage. In this case, the hybrid solution provides significant savings as compared to both pure HDD and pure SSD solutions over a 5 year span. The Hybrid storage solution, which utilizes tiering technology, lowers TCO in multiple ways:
- Reduces server count – Adding SSDs to a server using tiering increases the efficiency and performance of each server. Each individual server can handle more transactions than a pure HDD solution therefore fewer servers are required.
- Eliminates over provisioning of HDDs to meet performance requirements – It is common to overprovision the quantity of hard drives in a solution in order to achieve the required level of performance.
- Eliminates over provisioning of SSDs in an all flash array to meet capacity requirements – While an all flash array does provide uncompromised performance, it can be cost prohibitive for most applications that have capacity requirements.
- Reduces power and cooling costs – Power and cooling represents a significant portion of ongoing operational costs. Power usage is lowered by the combination of fewer servers, fewer hard drives as well as adding energy efficient SSD drives. A bonus in a tiered hybrid solution is that the capacity, of the SSDs are additive to the volume capacity.
Other savings include simplicity, management and software – The TCO chart above does not include other cost savings such as software costs. These costs are very dependent on individual applications but reducing server/processor count can also result in significant savings in software licenses. Additionally, reducing server count can also reduce floor space requirements, which can add to costs depending in locations of the data center. Also, we cannot forget about the impact of simplicity. Fewer servers means fewer components, cables, switches etc, which leads to both hardware and management savings.
From the standpoint of pure capacity, it is hard to argue that high capacity drives offer the best value, just like it is hard to argue that pure SSD offers the best performance for those large budget applications that require guaranteed response time. Unfortunately, users storage requirements are not that black and white. Fortunately, there is a solution that satisfies the requirements of the majority of applications that lie between these two extremes. Tiered hybrid storage offers SSD performance with high capacity, but best of all, it offers the lowest total cost of ownership. If performance and capacity are required, the choice is simple – Tiered Storage.