Yes, it’s a three step process: Upload, Build, and Download.
The Upload/Download parts are dependent to the internet speed.
The Build part for Win32/Win64 is currently very slow and we’re actively working on improving it (From several minutes down to only 5-10 seconds depending on content). We should have some improvements in a few releases from now.
In your case, the logs says it takes exactly 6 minutes, so if your build takes exactly 10 minutes (does it?), that means it took 4 minutes to upload your source. It’s relevant since I need to figure out a good timeout value for the Download step.