前台服务是否在睡眠模式（而非打瞌睡模式）下存活？

Question

So i have read a lot of posts about android services and their lifecycle during doze.

So far:

Background Services are restricted by doze mode.

Foreground Services are immune from doze mode. Meaning that they continue to have access network and etc.

There are plenty posts about doze mode and foreground services and none of them are referring to what happens to foreground services when sleep mode kicks in.

Sleep Mode - means CPU will be sleeping and will not accept any command except from RIL(Radio Interface Layer) and alarms. CPU will go to sleep mode with in fraction of seconds after LCD is turned off.

Doze Mode - means that apps on your phone will have no network access, the system will ignore “wakelocks” when apps try to keep the device from going to sleep, and no background tasks will be allowed to run. That certainly makes it sound like your phone won't do you much good, but there are a few ways Doze preserves functionality. While apps can't wake the device up to run sync jobs and other background tasks, high-priority push messages will still show up. So for example, a Hangouts message will appear on a device that's in Doze mode.

App Standby - an app that goes into standby loses all network access and all its background sync jobs are suspended. These restrictions are temporarily lifted when your phone is plugged in and for a few minutes every day or two. This gives suspended apps a chance to run any pending sync jobs, but they won't be allowed to continue running. A high-priority push notification will also be able to wake an app from standby for a short time.

Questions:

1. Do foreground services also pause when in sleep mode? If yes, do they restart or continue from where it left off?
2. Does the device even get to sleep mode when having a foreground service active?

Answer 1

Foreground service still alive during Doze and Standby. I checked this. My app is local proxy with tcp sockets. But... network module is going to sleep. My proxy continues to work, port stays open but connection to network will be lost for the reason of network sleeping during Standby. Simple push power button - and ups, packets begin to go out. Now searching for wakeup device programmatically on connection timeout condition

Answer 2

Sleep mode is same as doze mode. As foreground services are not affected by doze mode, so you should be fine using the foreground service.

Ex: running song using foreground service