After some amounr of time random players will get gamebreaming lagg when looking at dropped items, entities and portals. When you break the portal and re-light it it's fixed for the player who lit the portal.

I'll have to try and recreate it, which could take some time as it seems to happen randomly, do you want the client log or the server log?

edit:

I don't have sodium or optifine installed, I do have phosphor and lithium, to try and cancel out the lag which didn't work.

When it's lagging press F3 and take a screenshot. And post the log. Do you have optifine or sodium installed?

Client log.
And try to remove phosphor because it may be an incompatibility

Client log.
And try to remove phosphor because it may be an incompatibility

This is off topic for this issue but I usually use phosphor and I'm fine so I don't think it's an incompatibility.

Close due to not having complete information to diagnose the issue.