Maybe the reproduce:

1. prepare TPCC 10k warehouses and set tiflash replica 1
2. stop tiflash node
3. alter table customer drop primary key
4. start tiflash node

The Tiflash server store size decreased very much

The Grafana url is http://172.16.6.27:3009/d/SVbh2xUWk/simple-tiflash-summary?orgId=1&from=1620724839540&to=1620725512568