>The fact is, persistent DB connections aren't really that great for websites, where you need a few resources quickly and then nothing for a long time. Having 10,000 idle DB connections is a great way to eat up resources. But you can do it.

Which is why you should be using connection pooling. Which can not be done efficiently with PHP. Necessitating that people create an entire extra layer of database proxying software to do the pooling for you.