Also:
PHP message: PHP Warning: Parameter 1 to W3_Plugin_TotalCache::ob_callback() expected to be a reference, value given in /wp-includes/functions.php on line 3549" while reading response header from upstream, client: 105.188.192.209, server: xxxxxxxxxx, request: "GET / HTTP/1.1", upstream: "fastcgi://unix:/run/php/php7.0-fpm-staging.sock:", host: "xxxxxxxxxxx"
After fixing that, performance were up again
Just as a curiosity, how did you ‘fix that’? (I mean what changes did you make to which file?)
Ah yes, sorry, in the mean time I saw that as well. However, I’m now questioning if W3TC works at all. That small change definitely fixed the warnings, but somehow, I don’t see any content being cached on disk… not even the directories are being written (i.e. deleting them and reinstalling W3TC does not help). Maybe it’s just my configuration, though…
it works for me: Apache 2.4 / PHP 7.0 / Ubuntu 16.04
All right! So that might be a nginx issue, then, because that’s what I’m using (also on Ubuntu 16.04).