I am a big fan of Drupal and have used Drupal on more than 50 websites so far. My team has noticed many issues with performance for a website which was serving high traffic. We used modules like Boost for static file caching.
Some programmers i consulted told me that we should look for database optimization. So, i hired a person for DB optimization. He made a profiling tool to records all the queries our Drupal site makes.
Now, the site serves around 10k visitors in a day. And the number of queries for the last 12 hours are 6.1 million.
Some Facts important to be mentioned here
We are using very limited Modules
Views >> Recently stopped using the most popular and recent popular due to performance issues. But views is still enabled.
AcidFree Galleries >> Showing last three images post in galleries
We do not log access files due to performance reasons.
Server has 6 GB RAM, Intel Quad Core, Fast Hard Drive
Now, I want to ask, why Drupal makes so many queries ? Even if we do not install too many modules (in our case, around 3-4 modules, in addition to the core modules of Drupal), this number is too big. 12 million in a day for 10 K visitors ?
Drupal may work fine for small websites, but for websites which start getting some traffic, this CMS doesn't seem to work as good. Is there a need for Drupal team to check on the performance side ?
Regards