Hello,
First, let me tell you that fixing problem with DatabaseTasks_sqlsrv class won't give much speed up to your website. There could be many reasons why your website is taking more than 10 seconds to load - bad written queries (very likely), bad coding, missing files, server configuration (unlikely). I would need to investigate to fix the problems as it is never single problem that needs to be fixed. At the end I will show you list with all the things that has been fixed.
I am from Poland. I have great experience as Drupal developer - I specialize in creating and customizing websites to client's needs. I can do advanced things in Drupal - if you need anything done in Drupal - I can do it. It's a matter of how much time I need, not if I can do it or not. I think that's important, because many Drupal developers just can't do nothing more complicated than configure module or use preprocess hook.
If you need more information I would gladly answer your questions, but to briefly tell you what I can do, here's my experience and skills:
- highest completion rate on freelancer.com,
- over 100 A+++ ratings,
- over 5 years of experience in Drupal development,
- over 8 years in other fields (html, css, ajax, php, mysql),
Regards, Darek