NBT-data are sent for each command-block every time the 'previous output' is updated (This is obviously useless - the client does not care). This kills every bandwidth even with just 100 command-blocks.
The solution would be quite simple: Do not send the NBT-data immediately, but only when a user opens the GUI (this is the only case the client needs it)
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Thanks for the hint. But it's still useless to send the stuff every tick/activation (and, while it might not be a traditional bug, it is still bad behavior). Not to mention that I might want to have the output, but this seems impossible since my bandwidth is not infinite (what I would need if I let the output on)
This is no bug, it's coded to work like this.
You can switch off the output of the command block with the [X] besides the output line.
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