Cold starts with SSG on the first page load on Vercel

Answered

Shikoku posted this in #help-forum

ShikokuOP

2023-10-23T09:29:45.000Z

Is there any way to get rid of cold starts in the context of SSG in the App Router? HTML files are generated and ready to go, so I don't understand why the server takes 2-3 seconds for the first page load. I don't want any dynamic behavior, just rendering the HTML file that has been built at built-time.

There is no such cold start in export mode. I tried adding dynamic = 'error' and dynamicParams = false, but I'm still hitting cold starts for all pages after every deployment on Vercel.

const SSGPage = ({ params }) => <div>SSG: {params.slug}</div>

export const generateStaticParams = () => Array.from({ length: 100 }, (_, i) => ({ slug: `${i}` }))

export const dynamic = 'error'
export const dynamicParams = false

export default SSGPage

This code is deployed here if you want to see what I am talking about:

https://minimal-gamma.vercel.app/1

Pick a number between 1 and 100 that hopefully no one has used before directly in the URL to see the 2-second load.

Answered by Shikoku

Thanks for your patience with this. I have now had confirmation from the team that the difference you're seeing in the time for the initial render when it's PRERENDER is currently expected behaviour. This is due to the way the initial request is fulfilled. For a fully static page, or using output: export to set a page as fully static when not using revalidate, the first response is served from the cache initially. When using the app or page router to render all pages at build time, even with no revalidation, the initial page is not served from the cache, but is added to the cache after the first response which is why subsequent requests to the page are faster.

In this case, the team is aware that this could be improved and they are working on that as part of their backlog tasks. However, I don't have a timeframe for when any improvements would be released but I have made them aware of your use case and need for this.

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@Shikoku Is there any way to get rid of cold starts in the context of SSG in the App Router? HTML files are generated and ready to go, so I don't understand why the server takes 2-3 seconds for the first page load. I don't want any dynamic behavior, just rendering the HTML file that has been built at built-time. There is no such cold start in export mode. I tried adding `dynamic = 'error'` and `dynamicParams = false`, but I'm still hitting cold starts for all pages after every deployment on Vercel. jsx const SSGPage = ({ params }) => <div>SSG: {params.slug}</div> export const generateStaticParams = () => Array.from({ length: 100 }, (_, i) => ({ slug: `${i}` })) export const dynamic = 'error' export const dynamicParams = false export default SSGPage This code is deployed here if you want to see what I am talking about: https://minimal-gamma.vercel.app/1 Pick a number between 1 and 100 that hopefully no one has used before directly in the URL to see the 2-second load.