Back in June, I did manage to test PHP 7.0 (Alpha release 1) on my IIS 8.5 / MariaDB where I noticed 30% (not calculated) performance increase using PHP 7. While I have done re-tests to know performance difference, which you'll be able to find in screen shots/ tables below.
Recently my one of the shared hosting provider made PHP 7.0 (RC 4) available making me thinking of testing the claim of faster performance in PHP 7 and how much performance increase can be achieved particularly in Moodle. Whilst I already tested PHP 7 the day it released as Beta and I was impressed with results, but few things didn't worked for me to wait until RC versions started coming out. This tests includes both cases of Zend OpCache enabled and disabled so users can have idea how much OpCache alone can bring difference to the Moodle's performance.
I am using shared hosting environment with following resources allocated.
One thing to mention here, the web server I am using is LiteSpeed as opposed to Apache, so those who want to test on theirs, your results may vary based on plenty of factors and that includes web server performance factor where LiteSpeed is faster in performance when compared to Apache.
I haven't done advance tests like JMeter, for I am limited with what I can and cannot do on a shared hosting environment. So I am relying on "Performance Information" from the footer of the theme. The theme I am using is Elegance (Latest one), for I have mentioned theme for different themes have different code to render the page effecting the whole output.
Test is done on a course page with 7 Labels and 77 Page Module links (so fairly moderate course size). Browser window is refreshed 3 times before taking readings.
The tests were done using:
PHP 5.6 - OpCache Disabled
PHP 5.6 - OpCache Enabled
PHP 7.0 (RC4) - OpCache Disabled
PHP 7.0 (RC4) - OpCache Enabled
I am attaching the screen shots of "Performance Info" from Theme footer.
Test 1 - PHP 5.6 - OpCache Disabled
Test 2 - PHP 5.6 - OpCache Enabled
For those who want to know if using OpCache really makes a difference, then this above screenshot will be good enough to prove that, where not only time taken to render the page has decreased, as well amount of memory used has drastically reduced.
Test 3 - PHP 7.0 (RC4) - OpCache Disabled
Where just using PHP 7.0 roughly took same time, but see the amount of memory used, its almost halfed.
Test 4 - PHP 7.0 (RC4) - OpCache Enabled
And summarizing below, with % of improvement over PHP 5.6 both with and without using OpCache.
Now I am looking forward to Tim if he can manage to do the high level tests using JMeter etc.