How much RAM will I need?

I host a 24/7 survival server with minimal plugins.

These plugins include the following:
- LWC
- Core Protect
- World Edit and World Guard
- Vault
- Essentials Core
- Group Manager
- ZavAutoMessager

I currently have 1gb RAM and I have around ~20 people on at a time. It starts to lag around 15-16 people. I was thinking about upgrading to 2gb RAM, will this be enough?

 

I had a 1GB server with way more plugins and roughly 20 people. It was fine. 2GB will be more than enough.

 

Rardical Problem is, people are spread out on my map so there are more chunks loaded causing us to use more RAM

 

Might I suggest you uses two essential plugins when it comes to reducing lag? Both ClearLagg and WorldBorder significantly reduce the amount of RAM required to run your server.

I suggest first installing ClearLagg, then saying /lagg unloadchunks, which does what the command suggests. (No world data is lost when doing so) As well as that, say /butcher periodically to kill all hostile mobs, while keeping in mind that players with mob farms won't be happy with that.

Afterward, get WorldBorder and set the bounds to 10,000 blocks from the center of your world. (This expands 10,000 in all directions)

I recommend 2 gb RAM if you can afford it, because it will definitely be beneficial to your players' lag amount on your server.

I forgot to mention, the WorldBorder can be any amount, but I use 10,000 on my 2gb server and it works fine.

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

A good server has about 75-100 Mb per person. So if around 20 people are always on then you should have about 1700 Mb's of RAM which is ~1.660156 Gbs of RAM. So I would recommend 2 Gbs because you will have the plugins and you want no lag. I also recommend to get NoLagg. You can download it here.