We preload classes for two reasons. Classes that are popular can be
shared and can increase the number of apps that can be run concurrently.
Classes that initialize slowly can be initialized at system boot time
by the zygote, decreasing the time to launch a specific app.
To select which classes to preload, I exercised Android's built-in apps
as well as these apps from Market: ESPN score center, Amazon, Flixster,
Twitter, Adobe Reader, Ebay Mobile, Facebook, Solitare (Ken Magic),
Barcode Reader, Google Earth and Square.
A cycle of launching ~460 (non unique) activities in sequence took 9m35s
with the previous preloaded-classes list. The update improves the launch
time of the same sequence to 9m27s: the marginal improvement over the
previous set of preloaded classes is negligible.
http://b/3004763
Change-Id: Ida511ae31eeff6d95d9cb6aacae68b9bb9dd2ebe
Unlike previous releases where the set of classes-to-be-preloaded
was generated on a first-generation device (G1 and MyTouch 3G), this
round I used a second-generation device, a Nexus One. As a consequence,
class loading is faster (win) and fewer classes hit the 1250ms threshold.
Instead of sharing classes based on load time alone, classes are now shared
based on the number of applications loading them.
Change-Id: I18f7aa3e7e6258818871b3968b515c06314371b3
http://b/2546002
