This video is the first in a two-part video on investigating a GC memory 'leak'. This video discusses a real world memory leak that was found and corrected in PerfView itself. This first part discusses how you likely found the leak (by observing memory growth using TaskManager or a simmiar utility), and that some care is needed because not all memory growth is a leadk. The hallmark of a leak is unbounded growth when repeating an operation.
Also discussed is the the basic theory of taking two snapshots, one as a baseline, and another after doing an operation that should return the application to the same memory configuration.
Aftet watching this you should watch part two of this video. If you have not already done so, you should watch the video on GC Memory Investigation Basics. You may also be interested in the whole PerfView Tutorial Series.