server slow response time

The wait time in Pingdom is very slow response time. Is there a way to check?
Generally, anything under 100 ms is acceptable and good TTFB. In my case I am approaching the 300-400 ms range I might have something misconfigured on my server

 

The issue is, the browser does not utilitize one connection to get them (almost) all. That's why your "Web browser is connecting to the server and Web browser is waiting for data from the server" time might be a bit high each time.

It does fire up to 8 or 10 connections when it knows what to fetch, but it could do that much sooner and could fetch much more at once.

Use http2 to send multiple files over one lane:

Code:

    Header add Link "</css/styles.css>; rel=preload; as=style"
    Header add Link "</js/scripts.js>; rel=preload; as=script"

there are more options available.

You can use dynamic languages and smart caching headers to leave out the link headers on some (most) requests.
https://tools.ietf.org/html/draft-ietf-httpbis-cache-digest-02 soon


Edit: oh yeah, this brings mpm_worker ( please only event if you have backported newer apache, I assume its your debian 9 box ) leaves out mod_php mpm_prefork which boosts your stats on its own already.

https://de.wordpress.org/plugins/http2-server-push/
https://extensions.joomla.org/extension/http-2-server-push/
https://extensions.typo3.org/extension/http2_push/
https://github.com/terminal42/contao-http2
https://www.drupal.org/project/http2_server_push

 

does css and js need to be in the /js/ and /css/ directory?
can I do without it?

 

it is just an example, you can of course put them into root directory and use

Code:

    Header add Link "</otherstyles.css>; rel=preload; as=style"
    Header add Link "</yet/otherstyle.css>; rel=preload; as=style"
    Header add Link "</dist/generated.css>; rel=preload; as=style"

as long as they match the referenced path in your document.

You could set a session-cookie with a specific name depending on your (sub)resources and send headers based on that :

Code:

SetEnvIf PUSH_MAIN ^ PUSH_MAIN
SetEnvIf Cookie "(^|;\s*)pushmaincss=no($|\s*;)" !PUSH_MAIN
Header add Link "</main.css>; rel=preload; as=style" env=PUSH_MAIN
Header add Link "</main.js>; rel=preload; as=script" env=PUSH_MAIN
Header add Link: </logo.png>; rel=preload; as=image; env=PUSH_MAIN

https://www.w3.org/TR/preload/

 

i'm basically following this tutorial
https://http2.pro/doc/Apache

 

you can get additional ideas from
https://www.howtoforge.com/communit...be-enigma-munin-phpmyadmin-aliases-fix.77489/
https://www.howtoforge.com/community/threads/debian-9-php-5-6-7-2-with-sury-and-isp.79528/
https://www.howtoforge.com/community/threads/debian-9-install-mariadb-10-3.79531/
which will boost your performance if you use innodb or heavy logging compared to current debian stable

/etc/apache2/conf-enabled/http2.conf

Code:

Protocols h2 h2c http/1.1
ProtocolsHonorOrder On

 

Also enable zend opcode if you use php and not done already

Code:

opcache.enable=1
opcache.use_cwd=1
opcache.validate_timestamps=1
opcache.revalidate_freq=2
opcache.save_comments=1
opcache.load_comments=1

and if PHP prior 7.0.16 and 7.1.2

Code:

realpath_cache_size = "4M"

 

I see duplicates in the Response Headers
is "Header set Link" better?

Code:

    Header add Link "</otherstyles.css>; rel=preload; as=style"
   Header add Link "</yet/otherstyle.css>; rel=preload; as=style"
   Header add Link "</dist/generated.css>; rel=preload; as=style"

 

Also I need the Link Headers to work with all websites, ( wordpress, drupal, etc )

 

duplicates? https://tools.ietf.org/html/rfc5988#section-5.5 you can link multiple same kind resources together, however you might have some link headers, that's not bad, just try to keep the request / response small but efficient.

If you need them to work with all websites... well that's not my job Everything there to help you make it