Ssd me nvme difference

General
1

Hi.

I have a DS920+ and know it can take 2 SSD NVME Drives.

What will the difference be? Overal speeds of copy Quicker? I struggle with copy speeds.

Can I just add it and work on? Any difficult setup or change to current setup?

2

First some things that you could do without an M.2 NVMe SSD cache.

If you max out your Synology’s RAM, you will have more memory to use as cache. That could speed up read & write operations. (RAM cache is always faster than SSD cache.) If you use both of the Synology’s 1GbE ports and enable SMB multi-channel, you could increase (effectively double) the bandwidth, but your switch or router/AP and your client machines would also have to support network speeds faster than 1GbE, e.g. with a USB 2.5GbE dongle on your Mac/PC. Switching from HDDs to SATA SSDs will increase both read & write speeds. Choosing the right RAID configuration will also help, but you are limited to 4 bays on the base model, so there won’t be huge differences.

Whether M.2 NVMe SSD caches help, depends on your use case. Synology writes this (emphasis added):

SSD cache enhances 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. However, the benefits of using SSD cache are limited on certain workload patterns, in particular, large sequential read/write operations (e.g., HD video streaming) and entirely random data reading patterns.

I assume that in your case a read-write cache (with two M.2 SSDs) would be the right choice, but it will probably only improve speed for random small file reads and writes.

Here is a list of applications that would benefit from an M.2 SSD cache:

However, there are users who report that a read-write cache has improved things for them, especially via small file access for metadata and application data; see e.g. here: https://www.reddit.com/r/synology/comments/rvqsw6/comment/hr75nt0/ … so it can make certain things snappier and faster, but only for the UI, folder access etc., not for regular file copies via SMB, for example.