Limited cpu usage while chunk generation

[NXTler]

Hey, I tested this mod for an while now on my server(all the data down below) and I notice that while generating new chunks all threads are being used, but only running between 10% - 15% load. This is not the case for other loads. For example when I spawn a few thousend mobs the load an the cpu cores is scaling properly. I hope this can be fixed it whould give me the last push to switch from 1.12.2 to 1.15.2. I also hope you will continue working on this mod because its so powerfull and can bring some new life in servers. (Sry for my English im native german so :D)

Hardware: Dual Intel Xeon X5560 (12 Cores 24 Threads at 2,66Ghz) 164Gb of DDR3 RAM

Software: Linux Mint 19.1 Java 1.8.0_241 Forge-1.15.2-31.2.0 jmt_mcmt-0.17.54-1.15.2 preview OptiFine 1.15.2 HD U G1 (same problem even without but makes it all a bit more stable) no extra plugins or mods just bare minecraft

[jediminer543]

In theory minecraft does some of it's own parallelism for chunk generation; but I can see what I can do to make it more parallel

Also, nice hardware, I'm guessing old rackserver or something?

Also sorry for delayed response, have been having mental health issues

[NXTler]

@jediminer543 I did some more testing to world generation. Me and a friend found out that there is only limited power for world generation. In my case the limit is about 30% of all the cpu power. That means when one player is online he has all 30% of power but when there are two it seems to stay overall 30% so each only 15% power now. Any Idea what is going on here?

[KubiRemPL]

@NXTler I found the same problem with entites. My tps is going down but not any of cpu's are at 100%. I was testing on windows in that case, but still it's cool 23K entities and 16 tps. Spark doesn't give any good info.

The graph from procss explorer looks like this. I don't think MCMT likes HT.

[NXTler]

@KubiRem I quickly tested that on linux. In my case it was more or less going up too 100% but at one point only really slowly with the tps dropping and after about 60% or 80% the usage cpu was really jiggly. so it hit 100% at some time but not all the time.

[mcchouse]

I've been having the same sort of issue. There's 8 cores dedicated to my server (ubuntu) and as i watch the CPU usage during server startup it works great, using up 700-750% of the CPU (7-7.5 cores). When new chunks are being loaded, however, the server lags a crap ton while CPU usage remains around 150%. If you fixed this issue it would be heavenly, this would literally quintuple my server's speed. Thanks.

[KubiRemPL]

Hi @mcchouse The loading process of the server is threaded by forge, and the chunk gen is weirdly sort of threaded by minecraft. When using TerraForged with modified config I am using all of my cores at the same usage (usually near max of my CPU processing power) and chunks are generating without any lag and this generation is nearly instant, but chunk loading should be very light and asynced as well (by MC). Maybe I can help more if you will share more details?

Best Regards Kubi