Parallel Processing / Speed Up Generation?

[reedsutliff]

I am using Marp as part of a static site generation, in which i generate a slide cover image using --image jpg

I am running this against 40 presentations and it takes 1.5 minutes to process on github actions. I am doing the whole directory at one, so it seems like it would be trivial to parallelize the generation. Any ideas on how this could be done?

Thanks

[yhatt]

Interesting. A one of possible ways is running Converter.prototype.convertFile() in parallel within Converter.prototype.convertFiles(), powered by worker_threads module.

marp-cli/src/converter.ts

Line 273 in 8926641

for (const file of files) await this.convertFile(file, opts)

I feel there are a lot of barriers to using multi processes than you thought, e.g. a shared Converter class, the process handling of a singleton Chromium launched by Puppeteer, and compatibility with post-processing such as --server, --watch, and --preview.

[yhatt]

Currently I'm testing a simple parallelism (5 workers) on #628. It is already 4.5x faster than sequential PDF conversion 😎