view-distance

You can change the view-distance of your server by going to server.properties and changing:

view-distance=10

To a different number, for example:

view-distance=8

Default value: 10

Recommended starting value

view-distance=8

The render distance you choose entirely depends on:

• your server’s hardware (mainly RAM)
• how many players are online at peak times
• what kind of world your server has (flat minigame/event world vs open-world SMP, for example)
• how much lag you are experiencing
• whether your server crashes due to out-of-memory errors

I’d recommend startin with a value of 8, and then increasing it if your server can handle it or your players complain!

Players can always use mods like Bobby and Distant Horizons to increase their client-side render distance, without any load on the server.

View distance vs render distance

One of the first things you probably think of when talking about server lag is the render distance. There’s an important distinction to be made between view distance and render distance.

View distance

The view distance is a server-side setting that decides what the absolute maximum distance (in chunks) that the server will send to each player.

If this setting is set to 10, for example, the server will send chunks up to 10 chunks away from each player. Even if the player’s client has a render distance of, say, 16, the server will only send chunks up to 10 chunks away, and the player will only see chunks up to 10 chunks away.

From a server admin point of view, instead of thinking of view distance as “how far players can see”, think of it as “how many chunks the server has to load and send to each player”.

Render distance

Render distance is the client-side setting. It doesn’t decide what the max number of chunks the server will send, but rather how many chunks the client will actually render.

The client render distance won’t do anything if it’s above the server’s view distance, because the server simply won’t send those chunks to the client.

What range of chunks will be sent?

The number of chunks sent to the player is either the view-distance or) the player’s render distance, whichever is lower.

For example, if the server’s view distance is set to 8, and the player’s render distance is set to 12, the server will only send chunks up to 8 chunks away. Or, if the server’s view distance is set to 10, and the player’s render distance is set to 6, the server will only send chunks up to 6 chunks away.

Number of chunks sent per player

The view-distance is the radius of chunks sent to each player.

If you have it set to 10, it will send the chunks in a square, going 10 chunks outwards in each direction (north, south, east, west) from the player. That means that there will be 20 chunks in each direction (10 chunks in one direction, and 10 chunks in the opposite direction), plus the chunk the player is standing in. That means a total of 21 chunks in each direction.
In this case, the total number of chunks sent would be chunks.

You can calculate this as follows:

Exponential growth

From this, you can probably see that doubling the view distance doesn’t double the number of chunks sent to each player, it actually quadruples it.

You need to be careful when increasing the view distance, because even a small increase can have a big impact on performance - especially RAM usage, as I’ll explain.

CPU effect

The view-distance doesn’t affect CPU usage too much - sending more chunks does require more CPU power, but it’s not as significant as the RAM usage impact.

If you see ServerChunkCache on Spark taking up a lot of tick time, though, it may be worth lowering the view-distance to see if it helps.

RAM effect

The view-distance has a huge effect on RAM usage. Each chunk uses up a certain amount of RAM, and the more chunks you have to load and send to each player, the more RAM you will need.

If you’ve got a lot of RAM and not too many players, you can probably get away with a higher view-distance. However, if you’re running low on RAM or have a lot of players, you may need to lower the view-distance to prevent crashes.

Network effect

If you’re using a hosting provider, either from a datacenter or a specialised Minecraft host, you probably don’t need to worry about network usage too much.

If you’re self-hosting, however, you may want to consider lowering the view-distance if you have a limited upload bandwidth, or your network speed isn’t very good.

Sending more chunks to each player means a lot more data sent over the network.

If your server can’t keep up with network usage, you can see lag spikes.

Some example RAM values

Note: these were taken from a new Purpur 1.21.10 server with no plugins and a standard world, with one player online. These are likely not accurate.

• With a view distance of 10, a player joining added about 150MB of RAM.
• With a view distance of 30, a player joining added about 600MB of RAM.

The view distance massively affects the RAM usage. Be careful when increasing it.

An alternative: adaptive view distance

Some plugins, such as View Distance Tweaks, claim to adjust the view distance dynamically based on server performance.

If the server starts to lag, it lowers the view distance, and when the server is performing well, it increases it so that players cna see further.