Long render times

Discussed in https://github.com/quarto-dev/quarto-cli/discussions/1149

^{Originally posted by ma-riviere June 14, 2022}
Hello Quarto,

I'm wondering if there is a way to make Quarto (or Pandoc) use more threads/cores ?

I'm currently compiling a document to HTML (from R), and it takes more than 3 hours. The document is not that long: 2700 lines (more than half of those being text). There are no complex computations (the knitting in itself takes only a few minutes), but once it's done knitting, it will take close to 3 hours to output the HTML document (which is roughly 15MB in size).

During that whole time, only ~5% of my CPU is used by the Deno virtual machine, so I was wondering if there was a way to have it use more CPU resources to speed up the process ?

Thanks :)

Start with the linked Discussion #1149 and profile the HTML render path to establish whether Pandoc or the Deno virtual machine is the bottleneck. No file or test is named in the issue; a complete contribution would need a scoped performance change or documented threading support plus a reproducible timing check.