Quick answer: Start with 10 GB base, add player overhead, then add automation/chunk-loading headroom. Most active groups land between 12 and 18 GB.
Simple formula
Use this starting estimate:
Estimated RAM = 10 GB base + (players x 0.35 GB) + automation buffer
Automation buffer guide:
- light automation: +1 GB
- medium automation: +2 to 3 GB
- heavy automation/chunk loaders: +4 to 6 GB
These numbers are our own rule of thumb. The ATM team publishes no ATM10-specific server RAM recommendation, and the official server files cap the Java heap at 8 GB (-Xmx8G).
Examples
| Scenario | RAM target | Space-Node plan |
|---|---|---|
| 3 players, light automation | 12 GB | MC Special 1 (12 GB) |
| 8 players, medium automation | 15 GB | MC Special 3 (16 GB) |
| 12 players, heavy automation | 18 to 20 GB | MC Special 4 (32 GB) |
If your result falls between plan sizes, round up to the next plan. We start ATM10 at 12 GB for 1 to 5 players, 16 GB for 5 to 15 players and 32 GB for 15 or more, and heavy automation can push a smaller group into the next plan. Prices for each plan are on the ATM10 server hosting page.
Why servers still lag with "enough" RAM
RAM is only one part.
- CPU single-core performance matters for tick stability.
- Storage latency matters for chunk and save operations.
- Bad JVM flags can still create stutter.
Use this with ATM10 server requirements, ATM10 JVM arguments, and ATM10 lag fixes.
Allocation guidance
Do not allocate all host memory to Java.
Leave memory for:
- OS and filesystem cache,
- panel/agent processes,
- monitoring and backups.
One ATM10 detail: the official server files set -Xms4G -Xmx8G in user_jvm_args.txt. If your server starts through that file, its Java heap stays capped at 8 GB until you raise -Xmx to fit your plan.
FAQ
Is 8 GB enough for ATM10?
Not as a plan size. The official server files already use an 8 GB Java heap, and Java needs memory on top of the heap, so an 8 GB plan is too tight once people start building. Start at 12 GB.
Is 16 GB enough for ATM10?
For many active groups yes, if CPU/storage are strong and automation is controlled. It is the plan size we suggest for 5 to 15 players.
Can 24 GB be needed?
Yes, for larger player counts with heavy automation and many loaded chunks. There is no 24 GB plan, so go to the 32 GB plan (MC Special 4), which is also what we suggest for 15 or more players.