So basically, in 1.15.2 if you run while hitting in the ground with your sword, you start to lag. I've had some friends test this so i could make sure that it wasn't just me.
I could not upload the video here because it's to big, so i uploaded it on my YT channel.
Here's a link to the video:
Thank you for your report!
We're actually already tracking this issue in MC-157436, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
Quick Links:
📓 Issue Guidelines – 💬 Community Support – 📧 Customer Support – 📖 Game Wiki