I made a small plugin to pre generate chunks, using the world border api. This means that the command will create a task that will generate all the chunks within the world border over an amount of time.
The main command is:
/chunkpregen <start|stop> [<world>]
The world is optional and will default to the command executor, the console must specify the world.
And the start command allows the following flags:
--tickInterval <ticks> ~ Sets the interval between generation runs. (Default: 10)
--chunksPerTick <chunkCount> ~ Sets maximum number of chunks per tick to generate. (Default: Disabled)
--tickPercentLimit <tickPercent> ~ Sets the limit of tick time that can be used to generate chunks as a percentage of the preferred tick interval. (Default: 0.15)
--log ~ Logs info to the console, like the progress.
Example:
/chunkpregen start world --tickInterval 1 --chunksPerTick 100 --log
The flag names are exact as the method names in the link you posted, so you can check there for more info what they will exactly do.
Download: here
And if anyone is interested in the source code: here
Good luck 