A component may request that persistent storage be present in its incoming
/cache by using the
feature. This directory, unlike the storage provided by
isolated-persistent-storage, will be cleaned up by the system when disk
pressure is high. This cache cleaning event will walk every component's cache
storage and unlink everything it finds.
Because this cache cleaning event only happens under very specific situations, a
service interface named
provided to allow tests to cause cache clearing events. To exercise this
interface tests should cause components under test to populate items in their
/cache storage, the test should call the
Clear() function in
fuchsia.sys.test.CacheControl, and then the test should ensure that the
component continues to behave correctly when faced with this unexpected removal
of a file it needs.
Note that components not related to the test will also have their caches cleared
Clear() function is called. The function clears the cache of every
component on the system.
An example demonstrating test coverage of a user of