In my experience with technical interviews, the majority of time is spent on algorithm questions. This was especially bad at a recent interview I had at Google... all 5 interview rounds were almost entirely focused on one or two algorithm questions without any regard to any of the usual open-ended questions about past challenges, motivation, etc. I even had one interviewer start out asking about an interesting technical challenge I had, and basically cut me off after a minute or two with kind of a "ok thats great lets get on with the whiteboard now."
Technically I'm not supposed to reveal the exact questions they ask because they have candidates sign an NDA that covers the questions they ask during an interview. But it really shouldn't be too surprising the type of questions they ask, basically similar to stuff you see on sites like Leetcode or books like Cracking the Coding interview. Although very heavy on trees and graphs as opposed to the easier linked list/string/array type problems. Since it was an embedded position, there was on interview round where they asked some stuff about device drivers and Linux Kernel internals. Overall I thought it was a pretty bad interview for how "smart" Google is supposed to be. I thought Amazon actually did a much better job with interview questions, although they were still very algorithm-heavy.
