This document discusses various techniques for optimizing page load times in Drupal, including disabling unused modules, enabling caching, using a CDN, and investigating slow queries. It describes how the Authcache module works by caching rendered HTML for logged-in users. Various stages of Drupal's bootstrap process are outlined and their timings shown. Custom "thin applications" are discussed as an alternative approach, but they have disadvantages around maintainability, security and development speed compared to Drupal. Finally, opportunities for optimizing Drupal's rendering and bootstrap processes are suggested.

1. Respond in 60ms.
Extremal optimization with reinventing a
wheel

2. Artem Sylchuk
About me: Drupal developer since 2010

3. How long it takes to load a page?

4. 1,096,471 microsecs
24,824 microsecs
?

5. XHProf

6. Optimize it!
1. Disable and uninstall unused modules.
2. Switch to non-database cache backend.
3. Enable page caching, CSS and JS aggregation.
4. CDN
5. Install “caching” modules.
6. Investigate page load time using XHProf and/or NewRelic, etc.
7. Configure cron jobs and other background processes.
8. Optimize slow queries.
9. Authcache?

7. Do more caching...
The Authcache module offers page caching for both anonymous users and
logged-in authenticated users. This allows Drupal/PHP to only spend 1-2
milliseconds serving pages, greatly reducing server resources.
How does it work?
Authcache saves the final rendered HTML of a page to serve visitors. A separate cache is created for each user role as defined by the
administrator, so some roles can be excluded if necessary.
Authcache places priority on serving pages to the visitor as fast as possible. After a page is loaded by the browser, a second HTTP request may
be performed via Ajax. This initiates a lightweight DRUPAL_BOOTSTRAP_SESSION that allows SQL queries to be executed (such as updating
the user "history" table or node "statistics" table), and returns any user-customized data to the page (such as form tokens or default values on a
contact form).

9. How does Drupal load pages?
drupal_bootstrap()
3,294 microsecs
48,839 microsecs
63,089 microsecs
65,190 microsecs
66,188 microsecs
73,894 microsecs
687,986 microsecs

10. menu_execute_active_handler
1,639,028 microsecs

11. drupal_deliver_page
drupal_deliver_html_page
drupal_render_page

12. (Un)Real tasks?
● Less than 10 database requests
● Less than 100ms for the page generation
● More than 10 000 users per minute
● Page must be dynamic

13. History of Chiq.com

14. Thin applications idea

15. start
load bootsrap.inc
bootstrap session //
connect to DB, start
session
home
page?
Load homepage
application
search
page?
Load
Search
application
bootstrap language
bootstrap late page cache
check for canvas page
bootstrap path
yes
bootstrap FULL
finish
finish
Load
Drupal
finish
yes
yes
no
no
item
?
load item
application
no
finish

17. Result?

18. Cons
1. It is custom. Too custom.
● Maintainability.
● Security.
● Documentation.
● Complexity.
● Bicyclelity.
● Development speed.
● All other things why we prefer Drupal over a custom solution.

19. Is there a way to make it better?

20. Page delivery callbacks
Add headers, print content. They deliver.
● drupal_deliver_html_page
● ajax_deliver
● drupal_json_output (Media browser plus)
● admin_menu_deliver (Admin menu)

21. Renderable arrays https://www.drupal.org/node/930760
"Render Arrays" or
"Renderable Arrays" are the
building blocks of a Drupal
page, starting with Drupal 7.
A render array is an
associative array which
conforms to the standards
and data structures used in Drupal's theme rendering system.
In many cases, the data used to build a page (and all parts of it) is kept as
structured arrays until the rendering stage in the theming system. This allows
enormous flexibility in changing the layout or content of a page, and provides future
performance enhancements as well.

22. Views, panels, etc

23. hook_boot

24. Profit?

25. Main myth of Drupal
We do write the code.
A lot of code. “81792 lines” lot of code.

26. Drupal 8 - brave new world
Page generation time for anonymous user: 353,903 ms …
?

27. Future?
= ?

28. Questions?