How much RAM does an All the Mods 10 server need?

What do the ATM10 authors say about server RAM?

The All the Mods team publishes general figures and a heap example, and no number specific to ATM10. Its server setup guide lists "Server with at least 6GB+ allocated RAM (As required for most ATM packs)". Its Java guide (updated 3 July 2025) requires Java 21 for Minecraft 1.21 and later, says server arguments go in user_jvm_args.txt, and gives two examples: -Xms4G -Xmx6G with G1, and -Xms8G -Xmx12G with ZGC "for fast CPUs with 4+ cores & lots of ram (8-12GB)". Those are starting flags and not stated requirements for ATM10.

The ATM10 FAQ answers launch crashes with "Lack of RAM most likely" and sends server arguments to a Discord bot command. The Discord was not opened for this page, and the pack's CurseForge page refused automated access on 8 November 2026, so its current version could not be confirmed here. The ATM-10 GitHub README gives no RAM figure.

Space-Node, a host, says the 8.4 server files ship user_jvm_args.txt with -Xms4G -Xmx8G, a 1.26 GB zip holding 469 mods (setup guide, updated 1 Nov 2026). iTechGuides reports conflicting claims elsewhere, including one that no heap is set by default. Open user_jvm_args.txt in the exact server pack you download before copying any value.

What figures do other publishers give?

Publishers disagree because they answer different questions. This table lists each figure as reported on 8 November 2026, with the publisher's commercial interest.

iTechGuides labels its numbers "third-party planning figures, not an official ATM10 requirement." None of these publishers states a test method behind its number. WinterNode says its bands reflect what it sees on its own hardware and shows no data. BisectHosting's page also calls ATM10 a Minecraft 1.20.1 pack, while the ATM team's FAQ and repository describe it as 1.21 on NeoForge, so check any host page against the pack itself.

How much RAM should your ATM10 group start with?

Choose by concurrent players first, then adjust for automation. The last column is a reading of the table above, not a measurement.

Sellers disagree most at the top. WinterNode says "going past 16GB rarely helps" and warns that very large heaps lengthen garbage-collection pauses, while Space-Node sells 32 GB for that band. Space-Node's heap advice is to set -Xmx 2 to 4 GB below plan size, for example 13 GB on 16 GB, and PaperMC's general Java guidance is 1,000 to 1,500 MB below (PaperMC, Aikar's flags). Space-Node also notes that a heap left at the shipped 8 GB leaves the rest of a larger plan unused.

What changes how much RAM ATM10 needs?

Player spread and automation change ATM10 memory more than the headcount does, according to the hosts.

• Loaded chunks. Space-Node says RAM scales with loaded chunks, and that five players running in different directions cost far more than five in one valley.
• Automation. WinterNode says item transport, mob farms and chunk loaders push memory up steadily. The ATM team's lag guide recommends enabling Crash Utilities' disabled Item Clear on packs with farms and automation "to prevent massive entity leaks".
• World age. WinterNode says a world after two weeks of building uses more than on day one, so size for a few weeks in.
• View and simulation distance. WinterNode gives both defaults as 10 and suggests 8 and 6, or 6 and 4 with 10 or more players, while Space-Node says the pack's start script writes view-distance=8 and simulation-distance=5 when no server.properties exists, so check the file you actually have. Space-Node's load-testing guide says farms and machines outside simulation distance stop running while nobody is near them.
• New terrain. WinterNode suggests pre-generating a 3,000 to 5,000 block radius before opening the server.
• Meaning of "RAM". A plan's "12 GB" is usually total RAM, while -Xmx sets only the Java heap, so an 8 GB heap on a 10 GB plan can match a "10 GB" recommendation.

What CPU and storage does an ATM10 server need?

The ATM team publishes no CPU or disk figure for ATM10 beyond Java 21, so these numbers are sellers' advice. Space-Node labels its own table "our own advice, not official ATM figures": 4 cores at 3.5 GHz or better and 50 GB of NVMe for 1-5 players, 4-6 cores at 3.8 GHz and 80 GB for 5-15, and 6-8 cores at 4.0 GHz and 120 GB beyond that. The ATM team's ZGC example points the same way, asking for fast CPUs with four or more cores. Players need their own memory too: WinterNode suggests 8 to 10 GB allocated in each client.

Does more RAM fix a laggy ATM10 server?

More RAM does not fix low TPS on ATM10, because tick speed is mostly limited by CPU. If the server stays below 20 TPS while the heap has plenty of free space after garbage collection, adding memory will not change the tick time. The reverse case is real: too small a heap causes frequent garbage collection and out-of-memory crashes. Read MSPT and TPS explained first, then see how to find and lower high MSPT on ATM10. PaperMC's docs also say a server "should always be expected to use the entire Xmx", so a full-looking memory bar alone is not a fault.

How can you tell whether an ATM10 server has enough RAM?

Start from a published figure, then let your own server tell you whether it is right.

1. Set the heap inside your plan as in the table above.
2. Pre-generate the area your players use, so terrain generation is not mixed into your readings.
3. Play a normal session with your machines running. Space-Node's load-testing guide makes the same point about bots: most fake players don't build farms, run machines or open mod menus.
4. Run /spark health (TPS, CPU, memory and disk) and /spark gc (garbage collection history), from the spark command docs. The ATM team says most of its packs include Spark and the Observable profiler.
5. Run /spark profiler --timeout 180, the ATM team's three-minute snapshot, if TPS is low.

Use the server RAM calculator to compare these figures with overhead included, and see Java flags for modded servers for garbage collector choices.

What should you check on a host's ATM10 plan?

Check what a host's RAM figure actually covers before you buy an ATM10 plan:

• Whether the stated RAM is the container limit or the heap, and whether you can edit user_jvm_args.txt. PaperMC suggests asking whether the host will cover Java's overhead.
• Whether Java 21 is selectable, which ATM10 requires.
• The CPU model and whether cores are shared, since ticks depend on single-core speed.
• How many players the plan allows, and whether it can be upgraded without reinstalling.
• Whether the panel updates the pack safely. The ATM team says to back up the world and any changed configs first.

Which hosts fit a given situation is covered on the ATM10 hosting hub, based on published plans and terms rather than speed.

What would GameServerBench measure?

The planned protocol would run ATM10 at 10, 20 and 30 players on a pre-generated world, and record heap use after garbage collection and median and 95th-percentile MSPT from spark exports. Because bots skip automation, it would also replay a pre-built machine world. None of this has been run. For general Minecraft sizing, see how much RAM a Minecraft server needs.