Garry's Mod server lag usually comes from three things that the server pays for on every tick: the tickrate itself, the props and entities players spawn, and addon code that runs every tick. Memory is a weaker suspect: in our August 2026 boot test, an empty Garry's Mod server used 99 MB on a 2 GB plan.
What does tickrate do on a GMod server?
Tickrate is how many times a second the server simulates the world. The Valve Developer Community describes each tick: the server processes incoming player commands, runs a physics simulation step, checks the game rules and updates every object. A higher tickrate increases precision but "requires more CPU power and available bandwidth on both server and client."
The engine's own default is 66.6666 ticks a second, and the Facepunch wiki recommends 30 to 128. On a PlayNHost server the Tickrate setting starts at 22, and you can change it.
That is why tickrate multiplies everything else. Every prop on the map is part of the physics step, so a Sandbox server that copes at one tickrate can fall behind at a higher one with no other change.
Raise tickrate only after the server is stable at a lower one, and change it one step at a time.
How many props can players spawn in Sandbox?
Sandbox already caps what each player can create. The defaults in the gamemode's sandbox.txt:
| Convar | Limits | Default |
|---|---|---|
sbox_maxprops | props a single player can create | 200 |
sbox_maxragdolls | ragdolls a single player can create | 10 |
sbox_maxconstraints | non rope constraints a single player can create | 2000 |
The limits are per player, so the total on the map grows with the number of builders. Lower them from the server console or your server config if builds bring the server down. A negative value removes the limit, so check nobody has set one.
To clear the map, an admin (or the server console) can run gmod_admin_cleanup. It removes everything players have spawned and respawns the map's own entities. Add a type, for example gmod_admin_cleanup props, to remove only that kind.
How do addons cause lag?
Addon code hooked to Think or Tick runs on the server once per tick, so at a tickrate of 22 it runs 22 times a second, and at 66 it runs 66 times. Most addons do not tell you whether they do this.
- Add addons in small batches, so when performance drops you know which batch caused it.
- Know what players download. The server mounts your whole Workshop collection, but players are only sent the current map (if it is in the collection), the gamemode (if it names a Workshop id) and anything an addon marks with
resource.AddWorkshop. Lua files are sent separately. Each extra download slows joining, and the Facepunch wiki warns that marking Lua-only addons for download increases join times.
How do I find the cause of the lag?
Work through it in this order:
- Count entities.
ents.GetCount()returns how many entities exist. If the number climbs all session, props are your problem. - Check the physics. The Facepunch wiki's example below, placed in a server-side Lua file such as
garrysmod/lua/autorun/server/, prints a message when one physics step takes over 100 ms. - Turn off addons in batches and see whether the lag goes.
- Lower tickrate one step and see whether the stutter goes.
- Check memory last. Open your server's Usage graphs while players are online.
hook.Add("Think", "LagDetector", function ()
if physenv.GetLastSimulationTime() * 1000 > 100 then
print("Physics lag detected!")
end
end)
On our Garry's Mod server hosting, Tickrate and Workshop Collection are both fields under Settings, then Game Settings, and they are read when the server starts, so testing a lower tickrate takes a restart. Our Garry's Mod settings reference explains each one.
When is the plan too small?
When memory keeps reaching your plan's limit while players are on. Read the RAM tab under Usage during a busy session, not on an empty server. If memory is fine and the server stutters during builds, look at props, addons and tickrate first.
The smallest plan has 4 player slots. For a build server with a few friends, start there with the Sandbox limits in place.
The same diagnose-first approach applies to Minecraft: see how much RAM a Minecraft server needs.
