Oh. I've found it. I had x32 java installed, not x64, so i could not set more than 1 ram. Thank you for help.
Server still lags. What to do, how to fix that problem? I can't set more than 1 ram, why? Oh, and also, there is not version for 1.13.2.. EDIT...
How to pregenerate the world?
Are we rendering new chunks? Yes. Was the server created earlier? Yes
https://pastebin.com/cBtvfidC (i've player with my friends)
Yes, it lags a bit
still... It does not use more than 1% of system and server really lags..
What arguments? Xmx1550M -Xms1550M?
Why? UPD. It does not use more than 15% of accessible ram
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