Nexjs high average response time

[soheilnikroo]

We deployed a NextJS app with version 15.4.1 with SSR, and we use cache too, but the NextJS response time is too high, and it also gets down We use the method On-demand revalidation with revalidatePath

[Bhaathii]

Hi! 👋
I faced a similar issue with slow response times and server instability when using SSR + on-demand revalidation in Next.js 15.4.1.

A few things that helped me:

⚙️ 1. Avoid Revalidating Too Frequently
If you're calling revalidatePath() too often (especially for the same path), it can block the request or overload the server.

Make sure you're not calling it on every request or from multiple places.

Use logging to check if revalidations are stacking up.

🧠 2. Move Revalidation to Background
If you're using app directory (app router), ensure revalidation happens outside the request/response cycle if possible.

ts
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import { revalidatePath } from 'next/cache';

export async function POST(req: Request) {
setTimeout(() => revalidatePath('/your-page'), 100); // delay to free up request
return new Response('Revalidation triggered');
}
🚀 3. Use Edge Caching or CDN Layer
Even with SSR, using Vercel Edge Network or external CDN (like Cloudflare) can help cache full-page responses and reduce TTFB (time to first byte).

🔧 4. Profiling & Logs
Use:

css
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next dev --turbo --profile
Or enable Vercel Logs → watch for slow functions or route handlers.

[soheilnikroo]

Thanks @Bhaathii, I see the code, and I didn't use any revalidatePath at all. I think I found the problem, all of the pages are rendered dynamically based on the slug we request to the cms and get the data and render the page, but somehow NextJS renders a page on every request and doesn't cache i.t so, so I don't know what I'm setting up wrong, but I use these:
export const dynamic = 'force-dynamic';

export const revalidate = 300;
on my page.tsx. The thing that I think doesn't work is because of CPU usage. It seems that on every request, a dynamic rendering of that page is generated.

[soheilnikroo]

I found something, and I think it's working:

export const revalidate = 300;
export const dynamicParams = true;
export const dynamic = 'force-static';

[Gavrushuk]

@soheilnikroo, is it working, or have you made a change?
Do you also add generateStaticParams or render on demand?

[soheilnikroo]

@Gavrushuk Yeah, it worked for us, but what we do in the end is that we use an nginx as a sidecar to cache the HTML and chunks for 5 mins, SO the next JS dont get down. Why do we do this? Because we need a headers hook form next to that, it just works when we use force dynamic. Our use case is that we need a scalable subdomain, and we should fetch data from Strapi based on that domain config and paths. Also, each page renders fully dynamically based on strapi cms data. If you set the export const dynamic = 'force-static', you can use the headers from Next.js

[Gavrushuk]

@soheilnikroo Thanks. We don't need headers for dynamic pages, so I think we can do just force-static, and generateStaticParams for 100 last articles, but not sure if it will help us.
What is the average response time for crawlers in GSC before changes and after?

[soheilnikroo]

@Gavrushuk, for the metrica we set, before this solution with 2 pods in Kubernetes, for I think 2 core CPU and 512 MB memory, it gets down, I think, around 70rps. After the force static for the cold start, we have a spike around 1s, after that, we get 300ms - 700ms response time, since I recall