Large Markdown or Asciidoctor README are cut off at 512k bytes from repo front pages

[cirosantilli]

Minimal synthetic examples:

• https://github.com/cirosantilli/test-adoc-readme-large | http://web.archive.org/web/20190701071234/https://github.com/cirosantilli/test-adoc-readme-large
• https://github.com/cirosantilli/test-adoc-readme-large/blob/master/README.adoc | http://web.archive.org/web/20190701071238/https://github.com/cirosantilli/test-adoc-readme-large/blob/master/README.adoc
• https://github.com/cirosantilli/test-md-readme-large | http://web.archive.org/web/20190701071248/https://github.com/cirosantilli/test-md-readme-large
• https://github.com/cirosantilli/test-md-readme-large/blob/master/README.md | http://web.archive.org/web/20190701071256/https://github.com/cirosantilli/test-md-readme-large/blob/master/README.md

On the above examples, it can be seen that the README is cut off on the repo main pages at: 00000000031999, which according to wc is exactly 512000 bytes.

The blob view however shows up to the correct value of 00000000063999. Edit: as of 2020-06-04 there was an update, and now the blob view just says "Sorry about that, but we can’t show files that are this big right now.", which I'm fine with as it is a clear result. I'd rather have the cropped readme with a clear warning though.

Please either render the full thing, or give a clear warning somewhere that the README is being cut down.

I wonder if it's truly not technically feasible to render it somehow, since the corresponding github pages of those websites render fine: https://cirosantilli.com/linux-kernel-module-cheat/ I know this is a dynamic website, but maybe there's a way.

Real world examples:

• https://github.com/2019ncovmemory/nCovMemory "由于Github的错误，在初始页面README底部不会完整显示。请移步我们的网站或完整README阅读。"
• GitHub cut down the README.adoc of this repo at 512k bytes cirosantilli/linux-kernel-module-cheat#75

Oh, and the blame unicorns "This page is taking way too long to load": https://github.com/cirosantilli/linux-kernel-module-cheat/blame/d6d7f15c912ed6371c8cf15a93f43488d6fc5efb/README.adoc (archive).