I think this is a bit abnormal.
Have someone can investigate this situation.
F2Pool now have near 20% hashrate of BItcoin networt now (The sum of all china pool is alreadly over 50%), I think the situation should not continue, Bitcoin need more decentralize on mining.
Please inform people you know who mining Bitcoin in china pool, advice them pick one the another pool of any another countries, we need to distributing the bitcoin network hashpower to at least 2 – 3 (More is better) countries require to done the 51% attack.
Edit: 4 EH/s more on F2Pool now.