A look at memory on a 1GB DO Droplet

[Ed_S]

It’s really hard to make any sense of “free memory” because it’s a flexible resource which gets used for different purposes.

That said, you are a bit short - but so am I, in the same situation (78 active users in 7 days and 114 active in 30 days):

              total        used        free      shared  buff/cache   available
Mem:           985M        780M         63M         23M        141M         53M
Swap:          2.0G        1.1G        964M

I’ve written elsewhere and recently, perhaps follow up these other comments:

@Ed_S

And on the topic of memory, you should expect your RAM to be used. You will have swap, and that too will be used, and that’s one thing which can become a hard limit. Keeping an eye on free swap and on paging activity will let you know how that’s going. (Use top or free and/or vmstat for this.)

Also

@Ed_S

Essentially, RAM is fast and swap is slow. The operating system will make as much use of the RAM as it can, and this is why “unused RAM” isn’t easy to measure or think about. In your case, the big red proportion is RAM used to cache disk contents, which helps application performance. If that green proportion grew to more than say three quarters, that would be worrying. Maybe for some workloads, more than a half would be worrying.

You have two things to worry about, day to day: the performance of the forum, and the likelihood of a crash because you actually ran out of memory (meaning, your swap all got used and wasn’t enough). If you can monitor swap activity, using a provider’s dashboard or using ‘vmstat 5 5’ on the command line, I’d say do that. If you can monitor your forum’s responsiveness, maybe do that too.

And then month to month you find yourself performing an update, and that will need more memory than the day-to-day forum operation. If you are swapping heavily during an update, the update will take longer than usual. If your swap gets exhausted, you could have a crash and that could be really bad.

Your swap is already half-used - if you have the disk space to double it, do that.

Edit: maybe see also https://www.linuxatemyram.com/