page cache disk enhanced – ? characters appear

Interestingly the first time it builds the page its seems fine, however subsequent requests (probably when it grabs the cache file) is when the encoded characers start appearing ?

There are no characters in the database / content so this is being caused by the enhanced page cache.

The difference in page load times is around 100% – i.e. using basic its taking 4 to 6 seconds and using enhanced 2 to 3 seconds.

It only ever seens to occur on the front page ?

I’m seeing this behavior also, but not just on the front page.

Hmm, I’ve tried this on another site and I’m seeing this across all sorts of pages. Is this some kind of file encoding / header problems or white space in php files ?

Same problem. Disable Page Cache in W3TC fixed it, even if downgrading to 0.9.2.5 it was still broken after upgrading WP to 3.5.1.

For me, this issue occurs when page cache is set to Disk: Enhanced. Changing the setting to Disk: Basic eliminates the issue for me.

When Disk: Enhanced mode is enabled files are stored in a seperate folder (wp-content/cache/page_enhanced) with the following htaccess directives to apply additional encoding.

# BEGIN W3TC Page Cache cache
FileETag MTime Size
<IfModule mod_mime.c>
AddType text/html .html_gzip
AddEncoding gzip .html_gzip
AddType text/xml .xml_gzip
AddEncoding gzip .xml_gzip
</IfModule>
<IfModule mod_deflate.c>
SetEnvIfNoCase Request_URI \.html_gzip$ no-gzip
SetEnvIfNoCase Request_URI \.xml_gzip$ no-gzip
</IfModule>
<IfModule mod_expires.c>
ExpiresActive On
ExpiresByType text/html M7200
</IfModule>
<IfModule mod_headers.c>
Header set X-Powered-By “W3 Total Cache/0.9.2.8”
Header set Vary “Accept-Encoding, Cookie”
Header set Pragma “public”
Header append Cache-Control “public, must-revalidate, proxy-revalidate”
</IfModule>
# END W3TC Page Cache cache

I’m guessing that its an encoding problem caused by content being compressed more then once possibly, so I’m going to have a chat with my host to see what they say.

BTW I’m running Litespeed, anybody else or you running Apache ?

If you’re on Litespeed I did find this.

https://www.litespeedtech.com/support/forum/archive/index.php/t-5577.html

So I’m doing a little more digging.

I’ve started this thread in the Litespeed forum (see link below) which may help others and I have a paid ticket open with my host to optimise the environment.

https://www.litespeedtech.com/support/forum/showthread.php?t=6653

nisiwi, I was on litespeed yes. Then I changed to nginx and it just had another error in W3TC so I am just waiting for Frederick to fix it.

BTW, I have found nginx to be much faster versus litespeed in my tests. site loads in about 1.9s now. just worth mentioning as litespeed isnt cheap.

Thanks Keating thats interesting. From what most people say its a configuration issue in terms of delivering performance with each environment. However if the cost doesn’t offer an edge….why pay for it.

There are lots of conflicting tests and comparisons on all this so for now I’m sticking with Litespeed and maybe I’ll give nginx a try once I’ve got this resolved / stable so that I can compare results.

As you’re on a different environments it can’t be a Litespeed issue so much be a problem with the htaccess encoding rules somewhere in general.

nisiwi, it could be a litespeed issue. to clarify, as I’m on nginx now – I don’t see those weird characters any more. It’s just that enabling Page Cache Enhanced on nginx throws an error inside W3TC and won’t let me continue, it just defaults back to Page Cache Basic.

Note that I tried downgrading to 9.2.5 but the same issue occurs, it started when I upgraded to WP 3.5.1 so that’s the probable cause, something to do with the new filesystem.

Ok, understood.