Lumira display with Raspberry pi

Hi,

I am trying to use Raspberry pi as a kiosk server to connect to Lumira Cloud to display my Lumira page. But the speed is awfully slow and not stable.
(It takes more than 1 minute to show a single page with 8 small charts. Sometimes it just crashed.)

I'm using Chromium browser. According to the task manager, it takes around 35% of the CPU and 30% of the memory. The speed to open other website is fine.

Thanks,

Ping