[Plugin: WP Super Cache] Change of blog address creating cache errors

Here is an example of the debug log entries during a failure.

03:39:06 /category/1/ supercache dir: /homepages/blog/wp-content/cache/supercache/www.blog.com/category/1/
03:39:06 /category/1/ No wp-cache file exists. Must generate a new one.
03:39:06 /category/1/ In WP Cache Phase 2
03:39:06 /category/1/ Setting up WordPress actions
03:39:06 /category/1/ Created output buffer
03:39:07 /category/1/ Output buffer callback
03:39:07 /category/1/ Buffer is blank. Output buffer may have been corrupted by another plugin or this is a redirected URL. Look for text ‘ob_start’ in the files of your plugins directory.
03:39:07 /category/1/ No closing html tag. Not caching.
03:39:07 /category/1/ wp_cache_shutdown_callback: collecting meta data.

03:39:07 /category/1/ Buffer is blank. Output buffer may have been corrupted by another plugin or this is a redirected URL. Look for text 'ob_start' in the files of your plugins directory.
03:39:07 /category/1/ No closing html tag. Not caching.

This sounds similar to https://bit.ly/JGFKrt

Can you deactivate your other plugins and see if it’s still doing this?

Oh and I meant to ask you what you used to update the database with the new URL in all places. I always use a plugin called WP Move. I don’t think it will make a difference but maybe.

I have not tried deactivating all my other plugins. I will have to find a time to try this as my site is very plugin dependent.

As for change the URLs, I did this through he WP General settings page.

OK, i just deactivated all my other plugins and re-tested. according to the debug log, the error still existed…

17:40:38 /otp/ supercache dir: /homepages/20/blog/htdocs/blog/wp-content/cache/supercache/www.blog.com/otp/
17:40:38 /otp/ No wp-cache file exists. Must generate a new one.
17:40:38 /otp/ In WP Cache Phase 2
17:40:38 /otp/ Setting up WordPress actions
17:40:38 /otp/ Created output buffer
17:40:38 /otp/ Output buffer callback
17:40:38 /otp/ Buffer is blank. Output buffer may have been corrupted by another plugin or this is a redirected URL. Look for text ‘ob_start’ in the files of your plugins directory.
17:40:38 /otp/ No closing html tag. Not caching.
17:40:38 /otp/ wp_cache_shutdown_callback: collecting meta data.

although looking at the pages, i WAS getting a cached page and here is the snippet from the bottom of the HTML
<!– Dynamic page generated in 2.301 seconds. –>
<!– Cached page generated by WP-Super-Cache on 2012-04-18 09:39:46 –>
<!– Compression = gzip –>

You get cached pages (according to HTML comments) even when all your plugins are active?

Do you mean inactive?
I got a cached page when all my plugins BUT SuperCache were DEactivated

No, I mean when you reactivate them, are you still seeing the HTML comments that tell you it’s serving a cached page?

I just went and checked and yes, i’m getting a cached page
<!– Dynamic page generated in 2.169 seconds. –>
<!– Cached page generated by WP-Super-Cache on 2012-04-16 20:27:54 –>
<!– Compression = gzip –>

I did not deactivate and activate again. (only earlier today did I do that)

And this is on the new domain? (without www?) If so, then things are working.

OK, I guess my next question is this…
Why does the debug show an error?…

20:34:02 / supercache dir: /homepages/20/blog/htdocs/blog/wp-content/cache/supercache/www.blog.com/
20:34:02 / No wp-cache file exists. Must generate a new one.
20:34:02 / In WP Cache Phase 2
20:34:02 / Setting up WordPress actions
20:34:02 / Created output buffer
20:34:03 / Output buffer callback
20:34:03 / Buffer is blank. Output buffer may have been corrupted by another plugin or this is a redirected URL. Look for text ‘ob_start’ in the files of your plugins directory.
20:34:03 / No closing html tag. Not caching.
20:34:03 / wp_cache_shutdown_callback: collecting meta data.

or should I just not worry about it since it seems to be working?

I could be wrong but I think it’s a bug in the error logging. I wouldn’t worry as long as it’s definitely serving you those cache files. At least this helps Donncha (or any other developers) prioritize which bugs get fixed first.

OK, sounds good. Is there a method for submitting bugs or is this forum the appropriate way?

This is it. And even though this post has a bunch of back and forth, it has not been marked resolved so I’m assuming the head dev will still read thru it.

Support queries and requests should be made through the Super Cache forum.

source: https://ocaoimh.ie/wp-super-cache/

Have you added a .htaccess rule redirecting visitors from www to non-www?

WP Super Cache doesn’t cache redirects which I think is why the buffer is blank – WP is redirecting and not displaying anything.