It is time to upgrade my Synology DS214+ and this time I would like to start using the ‘docker’ function; I want to install Home Assistant and use that together with Homey.
I am looking at both the DS218+ and the DS718+
How ‘snappy’ is the DS218+ is, whilst running HASSIO in docker. Is that okay? Does it lag? Would the DS218+ be overkill?
I would rather invest in more disk capacity that redundant CPU capacity, so I hope the DS218+ is sufficient.
Any suggestions / experiences?
Thanks!
Looking at the specs (I don’t have either device myself), the DS718+ is about twice as fast reading/writing encrypted volumes, and is supports an SSD cache which the DS218+ doesn’t. Both don’t necessarily have to do with disk capacity, but they do with disk performance.
I think HA will run fine on the DS218+, I think RAM will be more of a bottleneck than CPU but both devices have the same amount of RAM (and also have the same maximum amount).
It depends of the other things you use your Syno for, but normally the DS218+ is more than sufficient for the average user. When running Docker, enough RAM is very important like @robertklep says.
When you want to run multiple containers or containers that need a lot of allocated RAM, expanding the RAM is a must. Therefor a DS218+ with extra RAM is a good buy, especially if you want to spend your money on more disk space. A DS718+ is better, but not needed for some basic stuff and running Docker only.
(I own a DS718+ myself)
Edit:
When only running a HA container, extra RAM isn’t needed.
Also consider DS220+ (the 2020 model of DS218+) is already announced for this summer, it will be available before 1st of september…
If you can wait, you can have or the latest model or have the 218+ probably for a better price 
