It's okay to set it to a number that makes sense for your use. Monitor your bill and impact on resources - make the decision based on facts. Generally speaking, blogs don't require near real-time updates - but if there is negligible impact on the bottom line - it doesn't matter.
Just know that if your site gets decent traffic, you will never stop busting cache and rebuilding pages/cache (making a lot of requests) if you have it at one second. However, this approach could be more cost effective than 1 request per user (SSR).
Objectively speaking, a few hundred pages could also build in around two to three minutes via a webhook, realistically, SSG could still be a valid option.
Here is a recap of the ISR process with a revalidation time of 1 second.
- Next.js can define a revalidation time per-page (e.g. 1 second).
- The initial request to the product page will show the cached page.
- The data for the blog post is updated in the CMS.
- Any requests to the page after the initial request and before the 1 second window will show the cached (stale) page.
- After the 1 second window, the next request will still show the cached (stale) page. Next.js triggers a regeneration of the page in the background.
- Once the page has been successfully generated, Next.js will invalidate the cache and show the updated product page. If the background regeneration fails, the old page remains unaltered.