How to make ReLaXed faster ?

This issue is intended as general discussion research on how to improve user experience by making rendering faster while avoid partially-rendered PDF documents.

Open questions:

• How to make sure the page is fully rendered before generating a PDF ? Right now this done by
  • Allowing figures and diagrams to be generated separately and included in the page as images/svgs, so that there is no rendering lag.
  • Waiting until “networkidle2” (this line) i.e. until no network exchanges, before rendering. I am wondering if this is too conservative, some pages dont need that and in my experience it really adds a lot of overhead. Would domContentLoaded work better in most cases ? If that’s the case, we can always let users a choice.

I am wondering if other solutions would make ReLaXed faster:

• Would puppeteer’s page.reload() be faster ?
• would a “hot reload” of the page where only a “diff” of the DOM is changed make the rendering faster ?
• Are there options Chromium startup options that would make it faster ?

Any other suggestions ?

[Zulko]

Since v0.1.4 ReLaXed is much faster, and also gives a better breakdown of it’s different rendering steps, which should make it easier to optimize particular cases in the future. Turns out that mathjax rendering was also a bottleneck so it is now optional and replaceable by the faster Katex.

[benperiton]

Yea, there’s quite a big jump! It does seem that the first run is always slower than the rest, not quite sure why that is, it does skew the average slightly but potentially some low hanging fruit to speed it up overall.