In the Tintri 2015 State of Storage report, survey results indicate that for data center professionals ensuring storage system performance (50%) and managing data growth (40%) are top concerns. As the amount of stored data grows exponentially, management of this information remains an increasingly difficult challenge for many organizations to tackle.
Tasked with fulfilling the growing demands of the business on even tighter budgets, this means that YOU must skillfully manage the performance of your storage infrastructure in order to keep the business running smoothly.
Managing Storage with Sub-LUN Tiering
Today, many storage vendors design arrays with various sub-volume level tiering capabilities to improve storage performance. Sub-volume tiering—also commonly referred to as Sub-LUN (Logical Unit Number) tiering—is the process by which blocks of data within a LUN are dynamically assigned to different tiers of physical storage within the array—SAS, Fibre Channel (FC), SSD SATA—depending on a variety of factors i.e. type of application, frequency of access, etc.
For example, arrays with sub-LUN tiering functionality will allow you to carve out LUNs with a heterogeneous mix of underlying drive types. The storage system will then move chunks of data between SSD and hard disk drives within the LUN based on predefined performance and efficiency criteria.
Different storage systems move data in different size chunks ranging from 8KB to 1GB increments and at varying levels of frequency. For example, let’s assume a storage system moves data in 1MB chunks to increase performance of a database application. If the hot chunk is 1MB in size, then the tiering system is 100% efficient. If the storage system moves chunks in 2MB increments, then it would only be 50% efficient as there may be cooler data moved along with the hot data.
While sub-LUN tiering can optimize performance given that the amount of hot data falls within the available capacity of faster tier disks, problems begin to arise when there is no longer enough high performance capacity within the LUN. Once hot chunks of data are forced to reside on slower SAS or SATA disks, performance degradation in the form of disk latency can quickly manifest, resulting in potential productivity and revenue loss for the business.
Given the growing demands being placed on storage systems, how can you manage storage performance amidst the inherent limitations of sub-LUN tiering technologies?
Software-Driven Sub-LUN Tiering is Here
With the VMTurbo storage control module, the software will understand the unique demands of each application, the performance capacity of your storage system from the LUN all the way down to the controller and array. It will then drive the decisions—storage vMotion, LUN migration or even a pool reconfiguration—to make sure your workloads get the resources they need in real time. In an environment with sub-LUN tiering working in conjunction with VMTurbo, once the amount of hot data has exceeded the available capacity on the faster tier and begins to experience unreasonable latency, VMTurbo will migrate—manually or automatically—the hot workload to a data store on a pool with the available space and IOPS capacity.
Armed with VMTurbo, you can rest assured that you are getting the most out of your sub-LUN tiering system, allowing you to focus on moving the business forward rather than responding to alerts.