Your NAS feels slow because your files are too small

Published 9 minutes ago

I am a Senior Author at XDA with a decade of experience covering consumer tech. I care more about the impact of technology on people’s everyday lives than the superfluous features companies keep adding each year, which is central to my reviews and product recommendations.

When a NAS starts to feel slow, most of us default to blaming the hardware. Maybe the CPU isn’t able to keep up with the power requirements anymore, or the RAM may be hitting its limits. I will start to question our decision to get 5400 RPM drives instead of 7200 RPM ones when setting up the NAS. The reasoning makes sense, but a NAS is such a complex device that there could be a zillion reasons for the sluggish performan…

Published 9 minutes ago

After living with a NAS for quite some time and watching it behave very differently depending on what I threw at it, I’ve come to realize that the bottleneck often isn’t the hardware. It’s often the files themselves — more specifically, how small they are.

The claimed transfer rates of hundreds of megabytes per second can definitely make people expect those numbers all the time. Those are indeed easy to achieve when copying large files, but you may be left disappointed if, say, you are trying to open a folder full of photos. What we need to realize is that storage and storage speeds don’t behave consistently.

The expectation of uniformity

The inconsistency is the actual reality

When buying a new NAS, people expect it to behave like a faster, bigger external drive. If a single file copies quickly, everything else should too. All the benchmarks and spec sheets aren’t doing enough to break that notion. Sure, faster drives and more RAM do mean a faster system, but storage speed definitely isn’t linear. The performance dips are real, but they aren’t something we expect, which leads to disappointment later on.

The delta between copying a large 40GB 4K Dolby Vision movie and moving some 20,000 photos to a different folder is massive. And that difference is exactly where the confusion about performance lives. In many cases, it comes off as inefficient. But it’s actually the NAS responding to two different kinds of workloads — that’s it.

7 reasons why drive speed doesn’t matter for NAS

Other factors impact NAS performance more than drive speed

The invisible tax of small files

Latency over throughput

Large files are the easiest to move. They are used as a benchmark for the speed figures that companies claim on spec sheets and marketing copy. When the system is moving a large file, it can easily hit the maximum claimed transfer speed if the entire transfer chain is optimized.

Small files, on the other hand, come with a lot of baggage. Each one has its own metadata, permissions, timestamps, author, ownership, checksums, and indexing information. All of that needs to be fetched and verified while the files are moving and before you see them in the destination folder. Now multiply that overhead by tens of thousands of files, and the cost in time becomes noticeable enough to be annoying.

Instead of continuous reads, the system has to deal with thousands of small requests and complete the round-trip over the network. This doesn’t pose an issue for bandwidth, but it does affect latency. And if you don’t already know, mechanical drives are perhaps one of the weakest links here because they aren’t as well optimized for random access as they are for continuous access. But that is not to say that SSDs are the answer. Small files are going to choke the system, no matter what kind of drive you use.

The slowest folders matter the most

The reality is that our NAS servers are full of small files — from documents and app data to RAW files and Docker volumes. This workload is almost always the one we interact with every single day. You might copy large files once a week, but you open and interact with your project files, notes, and media libraries probably dozens of times a day. So even if the NAS is objectively fast, it would still feel slow where it matters the most, and the perception of slowness would stick with it, too.

It’s not like you can’t do anything at all

Optimizing your NAS for small files could benefit you greatly. If your NAS feels slow, one thing you can do right now is schedule scans during off-peak hours so that your active work isn’t affected. Limiting real-time indexing would also help in the same way. You can take this a step further by creating SSD-only volumes where frequently accessed small files live exclusively. This will help cut down latency and make the experience faster, as SSDs tend to slash seek times and random read delays.

While reserving a fast pool for your actively used data is a sensible move, thinking about your archival system would also make your NAS feel faster. You can keep a slower pool for media libraries, backups, and long-term archives. Furthermore, you can bundle these archives into ZIP files and sort them by year to reduce the burden on the NAS.

The best thing you can do to fix the problem is to alter your expectations, not the hardware. If the NAS has started to feel slow with lots of small files stored on the system, maybe the NAS isn’t broken — it just needs some rearrangement. The NAS is behaving exactly the way it is designed to, but the problem is that we expect it to behave like something it’s not. Once you understand the problem and start paying attention to exactly where the friction lies, your problems with the NAS will disappear in a jiffy.

QNAP TS-464

Brand QNAP

CPU Intel Celeron N5095

Memory 8GB DDR4 (max. 8GB)

Drive Bays 4

Expansion 2x M.2 PCIe 3.0, 1x PCIe Gen 3 x2

Ports 2x 2.5 GbE, 2x USB-A 3.2 Gen 2, 2x USB-A 2.0, 1x HDMI

QNAP’s TS-464 is an impressive four-bay NAS with a striking design, powerful internal specs, and IR support for a remote control. If you’re looking for the best-equipped NAS for running Plex (or other media solutions) without spending a small fortune, this is the NAS for you.