I'm on an Android Galaxy S6, but the bug is also present on my laptop running windows 10 edition.

TL;DR: After travelling far from spawn, my minecraft world freezes for 1-2 seconds at a time, exactly once every 30 seconds.

I've been playing in one specific world of minecraft for quite a while, through many updates.
Recently, I traveled a long way from spawn (by travelling one direction in the nether and then making a gate) and then made a portal, walking back to spawn in the overworld. Just straight running in the overworld took around 30 minutes to return to spawn. My world size increased to 140-150 MB from around 80-90 MB.

Ever since this, my world consistently lags for around 1-2 seconds every 30 seconds. The time is completely predictable.

I copied the world to my laptop running the Windows 10 edition and experienced the same problem.

Playing as a client on the other device while not hosting causes the freeze on the hosting device, but not the client device.

The lag is completely unaffected by visual settings.

I'm not sure how acceptable this is, but given the size of the world file, I have shared it from my google drive as I am unable to attach it here.

https://drive.google.com/open?id=0B-NRsFEp5kmQX1JNanplNVp3N3M