You probably know SSDs are quite a bit faster than spinning hard drives. They've replaced conventional HDDs in most use cases, and might become the universal standard when prices become comparable to those of hard drives. You might be curious about SSD caching, and whether it could help you increase drive performance even more. By using an SSD as a dedicated cache, you can improve access times significantly, but the benefits aren't worth it on every system. With the right hardware, however, you stand to gain a lot, and setting it up is a breeze.

SSD caching can boost overall performance

But there's a catch

Put simply, SSD caching uses flash storage as cache memory to store frequently accessed data. Whenever data from the primary storage (the drive being cached) is accessed, the data is also stored in the SSD cache. When your system requires the same data again, it is fetched from the SSD cache instead of the primary storage. This is why SSD caching benefits systems where the drive being cached is a hard drive or an SSD slower than the one being used for caching.

Hence, most people using a desktop PC with an NVMe SSD as primary storage, or an all-SSD setup, won't find SSD caching of much use. Since the speed of the SSD cache is more or less the same as the base drive in question, there's little incentive to set up SSD caching on your gaming PC. On the other hand, using an SSD as a cache for your NAS or home server running multiple hard drives is worth it.

When you've set up SSD caching on your system, how it works is that each time a piece of data is requested, the system checks the RAM first. If it doesn't find it in the RAM, it tries the SSD cache. If it finds it there, it's called a "cache hit"; if it doesn't, it's a "cache miss." In the case of the latter, the data will be requested from your NAS hard drive after the system has exhausted all the faster options.

Setting up SSD caching on your NAS

A simple change in storage settings

Now that you know that SSD caching is worth setting up only on your NAS or home server, here's how you set it up. The process is quite simple — you simply need to add an unallocated SSD to an existing or new storage pool. Whichever NAS operating system you're using, accessing the storage and cache settings is pretty simple. From there, you can set up L2ARC, if you're on TrueNAS, by pointing the wizard to your chosen SSD.

SSD caching doesn't even need you to move your data across drives or anything like that. The performance improvements can be experienced immediately after configuring the SSD as the cache. This is highly preferable for people who don't want to move their data from hard drives to SSDs, but still want to boost performance using the superior speeds of flash storage.

Your gaming PC is better off with other upgrades

Your storage is already fast enough

I mentioned how SSD caching isn't worth it for most people who're already using fast SSDs for their operating system, games, and most other data. Another reason to look at other upgrades instead is that having more RAM (much faster than SSDs) on your PC will give you better results — the first place the CPU looks for the requested data is in the RAM. By upgrading to faster and more memory, you're essentially improving the more impactful link in the chain.

Upgrading to a more powerful CPU can also net you bigger performance gains compared to SSD caching. And this is not just about gaming or productivity performance. A new CPU can also help increase overall system performance in terms of multitasking and general responsiveness. You could play around with SSD caching on your Windows 11 PC just for kicks, but I can assure you it's not going to do anything for your PC's performance.

SSD caching can be game-changing on the right setup

If your PC already has most of the stuff on SSDs, you won't find SSD caching all that impressive. However, NAS and home server users must try it out, since hard drives can benefit a lot from a high-performance cache. When you're transferring tons of files, running memory-intensive virtual machines, or backing up your data, SSD caching can help keep your system responsive for longer.