android.os.health
Applications running in the background are responsible for a significant amount
of battery usage on a typical android device. There are several things that
applications can do in order to reduce their impact. For example, by using
JobScheduler, an application does not need
to independently monitor whether the network is available, whether the device is
plugged in, etc. In addition to being simpler to use, the application's
services are only started when the required conditions have been met. But even
when using the appropriate helper APIs, applications still can reduce their
footprint. This package provides more insight into what is going on behind the
scenes when an application is running.
Application data is tracked by which user id (uid) is using particular
resources. A snapshot of an application's measurements can be taken with the
SystemHealth.takeMyUidSnapshot()
method. The HealthStats object returned contains the
statistics.
HealthStats
In order to be returned efficiently, the HealthStats
class uses a set of int keys to identify the data returned. The
UidHealthStats, PidHealthStats,
PackageHealthStats , ProcessHealthStats,
and ServiceHealthStats classes provide those constants.
Each HealthStats object will be associated with
exactly one of those classes. The object returned from
SystemHealth.takeMyUidSnapshot()
will be using the UidHealthStats keys, as it contains all
of the data available for that uid.
Classes
| HealthStats | A HealthStats object contains system health data about an application. |
| PackageHealthStats |
Keys for HealthStats returned from
HealthStats.getStats(int) with the
UidHealthStats.STATS_PACKAGES key.
|
| PidHealthStats |
Keys for HealthStats returned from
HealthStats.getStats(int) with the
UidHealthStats.STATS_PIDS key.
|
| ProcessHealthStats |
Keys for HealthStats returned from
HealthStats.getStats(int) with the
UidHealthStats.STATS_PROCESSES key.
|
| ServiceHealthStats |
Keys for HealthStats returned from
HealthStats.getStats(int) with the
PackageHealthStats.STATS_SERVICES key.
|
| SystemHealthManager | Provides access to data about how various system resources are used by applications. |
| TimerStat | A TimerStat object stores a count and a time. |
| UidHealthStats |
Keys for HealthStats returned from
SystemHealthManager.takeUidSnapshot(int),
SystemHealthManager.takeMyUidSnapshot(), and
SystemHealthManager.takeUidSnapshots(int[]).
|