Due to MC-147818, chunks are not loaded by redstone lines. But instead of just updating to the new state of the redstone line once the chunk is loaded, it apparently keeps a list of changes that would have had to be done, had the chunk been loaded, and then executes them all at once as soon as the chunk is loaded.
If for example a long redstone+repeater line leads out of the render distance and it's toggled on and off without loading the repeater in the attached screenshot, that repeater will instantly turn on and off again once it's loaded, creating a zero-tick pulse. (The existence of zero-tick pulses is tracked in MC-8328, here it's just an easy way to visualise this bug.)
Attachments
Comments 7
After testing I believe this is related to MC-151057, not to border chunks.
Now they certainly do get their updates, but those just all pile up because the chunks don't load. That leads to the redstone line in my example setup getting zero-ticked and causing the repeater circuit to blink.
I think yes, the original version of this was caused by MC-151057, but the new one is caused by MC-147818. I wouldn't close it as duplicate though, because it might as well be something different. But I also won't add the version, because I'm really not sure.
If I understand this correctly, you have a repeater clock that gets stuck on a border chunk. Sending it another update breaks it later. That would be MC-147818, no?
It's not the clock that has problems, that is just there to visualise it. It's the redstone line itself. Also, the latest state is in my other comment, I should probably also update the description. The redstone line now does update, but only once I manually load the chunks (which is described in MC-147818), but now the scheduled redstone updates are apparently all queued for that block until I load the chunk, meaning that if I flick the lever two million times and then load the chunk, the repeater will blink a million times at once (which probably only results in a single zero-tick pulse and a lot of lag, but there might be other cases where it breaks a lot).
20w06a affected. To visualise power and depower long line that will make 0-tick pulse in unloaded chunks which can trigger sticky piston that lefts blocks.
I've noticed some repeaters staying on forever when not powered even if they were really close to me. Needless to say that for this reason or another (i've noticed very weird behavior with clocks) in this version alot of my redstone creation are no longer working