the owner is also running a bitcoin full node on a computer that can crash, be shut down/restarted,... for many reasons. and when you do that your node has to come back and report back to the front end (the website) about its mempool and all the fee rates which is what must have happened here.
That's what I thought until I've seen it in the second place.
Now I wait for more info. Did more research, it has to be a crash.
i wouldn't be surprised if btc.com were taking its data from jochen-hoenicke.de!
LoL !!!!
I would expect better than than that. I mean, they have their own pool, why would they use 3rd party data?
Also btc.com chart may be older that J-H one (at least I've heard of btc.com page way earlier than about the J-H page, but I am aware that this may not mean anything).
On the other hand.. other 2 charts don't seem to have the glitch:
https://mempool.observer/#historical-mempoolhttps://www.blockchain.com/charts/mempool-sizeMy current assumption is that certain software has crashed. If it was the same computer or not, I cannot tell.