We would like to thank Synology for supplying the review sample.
Almost two years have passed since the review of the DS916+, and we have today on our test bench its successor, the DS918+ which is equipped with a newer and slightly more capable CPU (supporting Intel's virtualization technology) and twice the RAM over the basic version of the DS916+ with 2 GB. Another strong advantage of the DS918+ is that it supports up to two M.2 NVMe 2280 SSDs, allowing for fast system cache creation without occupying any of the internal drive bays, which would reduce its overall storage capacity. This will mean a great deal to users who want to use the NAS as a fast storage server.
The DS918+ mostly targets the enthusiast home user; however, it lacks an HDMI port, which is an essential feature for every home NAS, at least in our expert opinion. Synology for its own reasons refuses to offer HDMI ports with its NAS products, while other major NAS manufacturers (QNAP, Asustor, and Thecus) have many models with more than a single HDMI port in some cases.
Like its predecessor, the DS918+ offers Btrfs and standard ext4 file-system support. The ext4 journaling file system is currently the most popular for Linux distributions, but within the last few years, some other file systems with more capabilities have emerged to address some of ext4's shortcomings. One of these fresh filesystems is Btrfs, a copy-on-write filesystem with support for a maximum file size of 16 EiB instead of the 1 EiB in ext4. Btrfs includes other interesting features, like snapshots, pooling, and checksums. One of the most interesting features of Btrfs is snapshot, a special type of subvolume that doesn't make copies of files, but shares the data and metadata of the subvolume, which makes it very fast and takes up very little space. A Btrfs subvolume's size isn't static since its space is dynamically allocated from the storage pool according to the data that is added or removed. Subvolume creation is also pretty easy, and a subvolume can even have nested subvolumes of its own. By default, there is always a top-level subvolume, which is mounted with all of its own subvolumes, but you can change the default subvolume to allow for a specific subvolume to be mounted without having to mount the subvolume that contains it.
For those of you who didn't understand much of the above, Btrfs offers better data protection than ext4, which is why Synology recommends you format the DS918+'s drives to Btrfs instead of ext4. However, we will use ext4 in our tests for our results to be comparable to those of other NAS servers in our database.