Recently I made a speed test between Magento Community Edition (ver. 188.8.131.52) and Magento Enterprise Edition (ver. 184.108.40.206). Here, I will show you the results of that test with short explanation of the testing procedure. For the purpose of testing, I made a little modification in index.php file from both of magento instances.
$start_time = microtime(true);
at the beginning, and
echo microtime(true) - $start_time;
at the end of the index.php file.
That allowed me to measure and print the execution time for each request (time is displayed as a floating point number in seconds).
The test was separated in three parts. First part was to measure response time for CMS page (cms/index/index in my case), second part was category page (catalog/category/view/id/5) and the third part was product page (catalog/product/view/id/19).
Magento Community Edition was tested both with and without cache enabled.
Enterprise Edition was tested in three variantes: first was with all cache disabled, second was with all cache enabled except full page cache (like the cache from Community Edition), and the third was with all cache enabled.
Final comparison is derived from previous tests for cases when all cache available is enabled, both for Enterprise and Community edition.
Whole test is created at the same machine with default Magento installations with sample data. There has been 20 requests per each test case. Tests are automated using Selenium testing system.