What Is SSD Caching and How Can It Optimize My NAS Performance

For modern storage technology, solid-state drives (SSD) have been a complete game changer compared to traditional hard disk drives (HDD). Compared to traditional HDD, SSD offer much higher IOPS performance and faster response times, but their capacity and durability are not as good as traditional HDD. The performance improvement also comes at a cost—a much higher cost that often negates the benefits of an all-SSD NAS. When running applications or environments that require higher IOPS, such as virtualized systems and databases, for example, building an all-flash memory data storage system can easily run into up to ten thousand dollars just for a 32TB NAS.

However, you can reap the benefits of SSD caching to enjoy the price savings of traditional HDD while having reduced latency, essentially optimizing both data efficiency and storage costs and enjoy the best of both worlds. SSD cache works by improving performance where input-output (I/O) operations require frequent access to randomly placed data. It can thereby benefit predominantly re-read workload patterns, such as mail servers and file services.

A NAS with SSD caching capability is especially worth considering for SMB looking to optimize their workflow without needing to spend too much, as lower-capacity SSD storage is highly affordable.

What Is an SSD Cache

A traditional HDD has many moving parts, and when dealing with higher occurrences of read/write requests (especially for a large number of small-sized files), it takes time for the drive to locate the data, resulting in latency. On the other hand, an SSD has no moving parts and uses flash memory, resulting in much higher data access speeds.

At its heart, SSD cache works by creating a temporary storage cache that stores frequently-accessed data on SSDs on a NAS. After you set up an SSD cache, any time an application accesses the system hard drives, data is stored in the SSD. Later on when the same data is required, the system will read the cached data from the SSD instead of the HDD. By storing hot or active data on the SSD, you leverage the faster speed and better responsiveness of the SSD to reduce latency, thereby delivering a noticeable improvement in NAS performance.

An SSD cache care be created by both hardware and software. Flash-based cache come in different form factors, including Nonvolatile Memory Express (NVMe), Dual In-line Memory Module (DIMM), PCI Express (PCIe), and Serial Attached SCSI (SAS).

Types of SSD Cache

When considering SSD caching, there are different SSD caching types available: write-through SSD caching and write-back SSD caching. Typically, write-through SSD caching writes data to both the hard drive and the cache. Whenever a user changes that file, both the storage and the cached copy will update. This dual-copy strategy ensures that changes are not lost if a sudden drive failure or power outage appears.

On the other hand, write-back SSD caching stores data writes to the SSD cache first, then updates the copy on the storage drive after the changes have been confirmed on the SSD cache. This version does not offer the safety of saving data in case a drive failure occurs, but offers higher performance for file operations.

Uses and Benefits of SSD Caching

SSD caching is specifically beneficial when it comes to memory-dependent tasks, thereby benefiting NAS storage being used in heavy file operations, such as file sharing, production data storage, or application server. SSD caching can also enable your NAS to run and manage virtual machines, as well as acting as a node in a HCI cluster. IOPS-demanding applications such as databases (online transaction processing, email servers) are also possible with SSD caching. Basically, anything that requires continual and systematic retrieval of data, you will benefit extensively from using an SSD cache.

When it comes to SSD caching, there are two limitations you will need to pay attention to for optimized performance: the SSD’s write endurance and the available system memory of your NAS. Write performance specifically refers to the maximum amount of data that can be written to the drive while it is under warranty. SSD lifespan is entirely determined by how frequently data is written to it. You will want to make sure that the SSD you choose for caching can withstand heavy write activity so it meets your IOPS demands.

Your system’s memory is important to SSD caching, as the amount of allocated system memory will determine the cache size. In order to mount a larger SSD cache, your NAS must have sufficient memory, about 1/4 of your base system memory to maintain SSD caching. Being able to expand your system memory will benefit your SSD cache.

SSD Caching on Buffalo TeraStation

An SSD cache is a way of obtaining faster storage, reduced latency, and improved all-round NAS performance and access speeds. SSD caching is the perfect solution for IOPS-demanding applications such as virtualization and databases, significantly improving the quality of workflow. With the price of SSD going up throughout the years, a NAS capable of SSD caching is a great investment to help optimize your workflow without stretching the budget.

Buffalo’s TeraStation 71210RH network storage is optimized for NVMe caching of up to 2TB. TS71210RH comes with expandable RAM for a larger cache and four native 10GbE ports that allow you to capitalize on the performance boost. The TS71210RH also comes with PCIe ports so you can attach SSD storage without needing to occupy the 3.5-inch drive bays, allowing you to maximize both your storage capacity and performance.

Buffalo prides itself in providing data storage solutions that offer the security, stability, and simplicity you need so you can store and manage your data with peace of mind. Responsible for many industry firsts and technology standards, Buffalo has four decades of networking and computer peripheral manufacturing and design experience. Contact us today to learn more about our secure network storage solutions and how they can benefit you.