Grafana direct rendering API is very very slow

Hi everyone, I’m using Grafana v5.2.0 on my localhost, I’m using postgres database.
When I’m trying to generate chart panel using direct rendering API, it is very slow. I have about 10 chart panels and 7 variables in this dashboard.

I want to know that: When I render a panel using panelId param, and provide all other variables, does Grafana query data for all panels inside this dashboard, then select the chosen panel to render, or just query & render the one that specified by panelId?

How can I speed up the rendering process? Does split the dashboard to multiple dashboard works?

Thank you!

you mean the server rendering? (using api/render) How long does your query take? the render api takes some time because it needs to spin up phantomjs and load grafana in this browser and then graps a image of the page

About 45s in average, but sometimes it goes up to over 180s.

Does Grafana render entire dashboard or just the selected panel? Does split the dashboard to multiple dashboard help?