Sometime between v1.0.0 and v1.2.1, we regressed on memory usage for apps that use lots of canvas drawing - e.g. the History of Everything app went from peaking around 6-700mb memory usage to peaking around 1.1 or 1.2gb memory usage.

This regression can lead to crashes on older iPhone's (e.g. 5 or 6) that only have 1gb of ram and memory limit you around 650mb for a single process.

I started bisecting this and will continue to dig in tomorrow - at this point, I suspect it may have been something in Skia. For what it's worth, using the Metal backend uses far less memory, at least according to the same readings from Xcode.

/cc @ened