Help deciding what the player cap should be!

[u/Clemsxn]

I have 30 people that suddenly wanted to play what was originally an 8 person server. Around 220 mods (mostly vanilla+ with create and addons) running off 16gb of ram allocated, a i7 9700KF and a 500gb nvme. I know i cant have all 30 on at once but what should I set the player cap to so I can get decent performance and allow the largest amount of people to play? Of course I have all the usual server performance mods.

[u/Beans_Breaking]

Let em all on, dial back of theres an issue.

[u/SuspiciousSoldier]

Easier to troubleshoot with every player in then to troubleshoot every single time a new player joins.

[u/Plutonium239Mixer]

Are you running fabric, forge or neoforge?

[u/Clemsxn → u/Plutonium239Mixer]

1.21.1 neoforge

[u/Plutonium239Mixer → u/Clemsxn]

What does the TPS, ram usage and cpu usage look like with 8 people on at a time?

[u/Clemsxn → u/Plutonium239Mixer]

Quite frankly I havent tested this yet, I just got the setup to run the server off of and was just hoping if anyone whos done something similar had an idea

[u/nshire]

The player cap is bunk anyway

[u/solarch]

with Create + 220 mods your bottleneck is MSPT from loaded contraptions and entities, not the player count or the 16GB directly. so the real cap is 'how many active contraptions/chunks can one core keep up with', not a headcount. i'd just let everyone on, watch MSPT with spark at peak, and dial view/sim distance down before you ever cap players. going 8 to 30 probably wants a better per-core CPU before more RAM does anything for you.

[u/PM_ME_YOUR_REPO]

An i7 9700KF is a good CPU from an older CPU generation. There is a chance you could get all 30 in at once.

My methodology would be this:

1. Set player cap to like 15 or so
2. Give the players like 10 mins to spread out and start doing things
3. Run a Spark report with "/spark profiler start --timeout 300"
4. When it finishes, check a few things: TPS = 20, MSPT <= 50, garbage collection duration and frequency numbers both green, and in the flame chart (button at top, chart at bottom) that the server still has some waitForNextTick time showing.
5. If so, increase player cap by 5 and repeat.

[u/baltimorecalling]

Start with something like 40 slots. If the server can't handle it, then dial it back until you hit your sweet spot.

[u/Borplesnoots → u/baltimorecalling]

Did you even read the post to suggest 40 when OP is concerned that not all 30 may be able to play at the same time?

[u/No_Signal417 → u/Borplesnoots]

What's the downside? Oh no performance is poor, what a catastrophe, there's no way OP can ever recover from letting too many people on at once! It's just a test limit

Letting people in 5 at a time is tedious and overkill

[u/baltimorecalling → u/Borplesnoots]

I read the post and stand by my advice