[android-developers] Re: service process priority: startService() vs bindService()
Still no anwsers/comments.. Not any specialist of Android Services?... On Mar 1, 8:06 pm, pedro242 pedro.contreir...@gmail.com wrote: Hi there, I would need your help to clarify what is the priority of a process hosting a Service when the service is either started (startService() ) or bound (bindService()): When the Service is started, the Android doc is quite clear saying: If the service has been started, then its hosting process is considered to be less important than any processes that are currently visible to the user on-screen, but more important than any process not visible. = it means that the process is ranked as Service process level (Cf. Processes and Threads android doc) As far as i understand, this priority level should warrant us the process will only be killed in a very constraining RAM configuration, and makes it suitable for long time running background thread.. Is my understanding correct? My concern deals with the bound case.. Android doc says: If there are clients bound to the service, then the service's hosting process is never less important than the most important client. That is, if one of its clients is visible to the user, then the service itself is considered to be visible. So if my most important client gets stopped and goes in the background (or even worse, is destroyed), the Service process is then ranked in the same way?? It would then mean that it does not keep ranked as Service process level (started case) and will be about to be destroyed by the system at any time.. So what the point of launching a background thread in a bound Service?? What's the difference between a simple thread launching from an Activity? Am i missing a point? Any comments? Thanks.. Pedro -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: service process priority: startService() vs bindService()
(Great! An answer from the prestigious M.Murphy!! Great books!!) Thanks Mark for your answer.. But the Services in bound mode are still not clear for me.. Android Doc says: If there are clients bound to the service, then the service's hosting process is never less important than the most important client. That is, if one of its clients is visible to the user, then the service itself is considered to be visible. So if my most important client gets stopped and goes in the background (or even worse, is destroyed), the Service process is then ranked in the same way?? wich means most likely to be also destroyed.. That is my real concern.. Mark, do you confirm my understanding? On Mar 5, 3:40 pm, Mark Murphy mmur...@commonsware.com wrote: On Tue, Mar 1, 2011 at 2:06 PM, pedro242 pedro.contreir...@gmail.com wrote: When the Service is started, the Android doc is quite clear saying: If the service has been started, then its hosting process is considered to be less important than any processes that are currently visible to the user on-screen, but more important than any process not visible. = it means that the process is ranked as Service process level (Cf. Processes and Threads android doc) As far as i understand, this priority level should warrant us the process will only be killed in a very constraining RAM configuration, and makes it suitable for long time running background thread.. Is my understanding correct? Please do not have a long time running background thread except in extreme situations (e.g., VOIP client), and even then you will need to use startForeground() to keep the service around. Pure background services (i.e., those without an accompanying activity in the foreground) are designed to run for seconds or minutes, not hours or days. So what the point of launching a background thread in a bound Service?? What's the difference between a simple thread launching from an Activity? Activities undergo configuration changes, where they get destroyed and recreated (e.g., screen rotation). Services do not. Dealing with either background threads or bound services is annoying to deal with in an Activity. -- Mark Murphy (a Commons Guy)http://commonsware.com|http://github.com/commonsguyhttp://commonsware.com/blog|http://twitter.com/commonsguy Android App Developer Books:http://commonsware.com/books -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
Re: [android-developers] Re: service process priority: startService() vs bindService()
On Sat, Mar 5, 2011 at 11:30 AM, pedro242 pedro.contreir...@gmail.com wrote: So if my most important client gets stopped and goes in the background (or even worse, is destroyed), the Service process is then ranked in the same way?? If your activity is no longer in the foreground (e.g., user presses HOME), then it and its service are not considered a high-priority process. If your activity is destroyed (e.g., user presses BACK, Android destroys the background activity to free up RAM), then your service will be destroyed, because you should have unbound from the service when your activity is destroyed. Please do not attempt to bind to services then leak them by never unbinding them. -- Mark Murphy (a Commons Guy) http://commonsware.com | http://github.com/commonsguy http://commonsware.com/blog | http://twitter.com/commonsguy Android App Developer Books: http://commonsware.com/books -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
Re: [android-developers] Re: service process priority: startService() vs bindService()
The service will be at the level of the most important thing it is doing. If it has a service that is started, and an application that is in the foreground bound to it, then it will be in the foreground as long as any such bound application is foreground. When the application goes to the background, it will be lowered to the service level (unless there is some other component or something else going on more important than the service). This is very different than just making a long running thread in the processes, which the system then doesn't know about and never prioritizes the process based on the thread being there. (And anyway you can't bind to a thread from another processes, so functionally you just can't do the same things.) Also please realize that just having a service started doesn't mean your process won't get killed except under unusual situations. In fact the current implementation ensures that, for a service that remains started a long time, its process will eventually get killed (and the service then restarted). On Sat, Mar 5, 2011 at 8:30 AM, pedro242 pedro.contreir...@gmail.comwrote: (Great! An answer from the prestigious M.Murphy!! Great books!!) Thanks Mark for your answer.. But the Services in bound mode are still not clear for me.. Android Doc says: If there are clients bound to the service, then the service's hosting process is never less important than the most important client. That is, if one of its clients is visible to the user, then the service itself is considered to be visible. So if my most important client gets stopped and goes in the background (or even worse, is destroyed), the Service process is then ranked in the same way?? wich means most likely to be also destroyed.. That is my real concern.. Mark, do you confirm my understanding? On Mar 5, 3:40 pm, Mark Murphy mmur...@commonsware.com wrote: On Tue, Mar 1, 2011 at 2:06 PM, pedro242 pedro.contreir...@gmail.com wrote: When the Service is started, the Android doc is quite clear saying: If the service has been started, then its hosting process is considered to be less important than any processes that are currently visible to the user on-screen, but more important than any process not visible. = it means that the process is ranked as Service process level (Cf. Processes and Threads android doc) As far as i understand, this priority level should warrant us the process will only be killed in a very constraining RAM configuration, and makes it suitable for long time running background thread.. Is my understanding correct? Please do not have a long time running background thread except in extreme situations (e.g., VOIP client), and even then you will need to use startForeground() to keep the service around. Pure background services (i.e., those without an accompanying activity in the foreground) are designed to run for seconds or minutes, not hours or days. So what the point of launching a background thread in a bound Service?? What's the difference between a simple thread launching from an Activity? Activities undergo configuration changes, where they get destroyed and recreated (e.g., screen rotation). Services do not. Dealing with either background threads or bound services is annoying to deal with in an Activity. -- Mark Murphy (a Commons Guy)http://commonsware.com| http://github.com/commonsguyhttp://commonsware.com/blog|http://twitter.com/commonsguy Android App Developer Books:http://commonsware.com/books -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support, and so won't reply to such e-mails. All such questions should be posted on public forums, where I and others can see and answer them. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: service process priority: startService() vs bindService()
Thanks Dianne for your answer.. I just compared the basic thread and a thread launched in a service process upon an AIDL request in the sense that if the client actvity was destroyed, then in both cases, the basic long time running thread and the service thread would also be destroyed... With your responses it's now more clear for me.. and by the way I realized it's make no sense in launching a thread upon an AIDL request from a component and expecting this thread keeps on running, after the component be destroyed. (Dianne, your Multitasking the Android Way paper is very very helpfull, keep on doing things in this way..) On Mar 5, 7:04 pm, Dianne Hackborn hack...@android.com wrote: The service will be at the level of the most important thing it is doing. If it has a service that is started, and an application that is in the foreground bound to it, then it will be in the foreground as long as any such bound application is foreground. When the application goes to the background, it will be lowered to the service level (unless there is some other component or something else going on more important than the service). This is very different than just making a long running thread in the processes, which the system then doesn't know about and never prioritizes the process based on the thread being there. (And anyway you can't bind to a thread from another processes, so functionally you just can't do the same things.) Also please realize that just having a service started doesn't mean your process won't get killed except under unusual situations. In fact the current implementation ensures that, for a service that remains started a long time, its process will eventually get killed (and the service then restarted). On Sat, Mar 5, 2011 at 8:30 AM, pedro242 pedro.contreir...@gmail.comwrote: (Great! An answer from the prestigious M.Murphy!! Great books!!) Thanks Mark for your answer.. But the Services in bound mode are still not clear for me.. Android Doc says: If there are clients bound to the service, then the service's hosting process is never less important than the most important client. That is, if one of its clients is visible to the user, then the service itself is considered to be visible. So if my most important client gets stopped and goes in the background (or even worse, is destroyed), the Service process is then ranked in the same way?? wich means most likely to be also destroyed.. That is my real concern.. Mark, do you confirm my understanding? On Mar 5, 3:40 pm, Mark Murphy mmur...@commonsware.com wrote: On Tue, Mar 1, 2011 at 2:06 PM, pedro242 pedro.contreir...@gmail.com wrote: When the Service is started, the Android doc is quite clear saying: If the service has been started, then its hosting process is considered to be less important than any processes that are currently visible to the user on-screen, but more important than any process not visible. = it means that the process is ranked as Service process level (Cf. Processes and Threads android doc) As far as i understand, this priority level should warrant us the process will only be killed in a very constraining RAM configuration, and makes it suitable for long time running background thread.. Is my understanding correct? Please do not have a long time running background thread except in extreme situations (e.g., VOIP client), and even then you will need to use startForeground() to keep the service around. Pure background services (i.e., those without an accompanying activity in the foreground) are designed to run for seconds or minutes, not hours or days. So what the point of launching a background thread in a bound Service?? What's the difference between a simple thread launching from an Activity? Activities undergo configuration changes, where they get destroyed and recreated (e.g., screen rotation). Services do not. Dealing with either background threads or bound services is annoying to deal with in an Activity. -- Mark Murphy (a Commons Guy)http://commonsware.com| http://github.com/commonsguyhttp://commonsware.com/blog|http://twitter.com/commonsguy Android App Developer Books:http://commonsware.com/books -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -- Dianne Hackborn Android framework engineer hack...@android.com Note: please don't send private questions to me, as I don't have time to provide private support, and so won't reply to such e-mails. All such questions should be posted on public forums, where I and others can see
Re: [android-developers] Re: service process priority: startService() vs bindService()
Service.startForeground does increase the chances that the service will keep running (as this puts the service into foreground process class). You can use this independently of binding, it's orthogonal that way. Can be useful if the user requests some kind of update from the network (for example) and you'd like to be able to finish it even if the user leaves the controlling activity before it's done. 06.03.2011 2:09 пользователь pedro242 pedro.contreir...@gmail.com написал: Thanks Dianne for your answer.. I just compared the basic thread and a thread launched in a service process upon an AIDL request in the sense that if the client actvity was destroyed, then in both cases, the basic long time running thread and the service thread would also be destroyed... With your responses it's now more clear for me.. and by the way I realized it's make no sense in launching a thread upon an AIDL request from a component and expecting this thread keeps on running, after the component be destroyed. (Dianne, your Multitasking the Android Way paper is very very helpfull, keep on doing things in this way..) On Mar 5, 7:04 pm, Dianne Hackborn hack...@android.com wrote: The service will be at the level of the most important thing it is doing. If it has a service that is started, and an application that is in the foreground bound to it, then it will be in the foreground as long as any such bound application is foreground. When the application goes to the background, it will be lowered to the service level (unless there is some other component or something else going on more important than the service). This is very different than just making a long running thread in the processes, which the system then doesn't know about and never prioritizes the process based on the thread being there. (And anyway you can't bind to a thread from another processes, so functionally you just can't do the same things.) Also please realize that just having a service started doesn't mean your process won't get killed except under unusual situations. In fact the current implementation ensures that, for a service that remains started a long time, its process will eventually get killed (and the service then restarted). On Sat, Mar 5, 2011 at 8:30 AM, pedro242 pedro.contreir...@gmail.com wrote: (Great! An answer from the prestigious M.Murphy!! Great books!!) Thanks Mark for your answer.. But the Services in bound mode are still not clear for me.. Android Doc says: If there are clients bound to the service, then the service's hosting process is never less important than the most important client. That is, if one of its clients is visible to the user, then the service itself is considered to be visible. So if my most important client gets stopped and goes in the background (or even worse, is destroyed), the Service process is then ranked in the same way?? wich means most likely to be also destroyed.. That is my real concern.. Mark, do you confirm my understanding? On Mar 5, 3:40 pm, Mark Murphy mmur...@commonsware.com wrote: On Tue, Mar 1, 2011 at 2:06 PM, pedro242 pedro.contreir...@gmail.com wrote: When the Service is started, the Android doc is quite clear saying: If the service has been started, then its hosting process is considered to be less important than any processes that are currently visible to the user on-screen, but more important than any process not visible. = it means that the process is ranked as Service process level (Cf. Processes and Threads android doc) As far as i understand, this priority level should warrant us the process will only be killed in a very constraining RAM configuration, and makes it suitable for long time running background thread.. Is my understanding correct? Please do not have a long time running background thread except in extreme situations (e.g., VOIP client), and even then you will need to use startForeground() to keep the service around. Pure background services (i.e., those without an accompanying activity in the foreground) are designed to run for seconds or minutes, not hours or days. So what the point of launching a background thread in a bound Service?? What's the difference between a simple thread launching from an Activity? Activities undergo configuration changes, where they get destroyed and recreated (e.g., screen rotation). Services do not. Dealing with either background threads or bound services is annoying to deal with in an Activity. -- Mark Murphy (a Commons Guy)http://commonsware.com| http://github.com/commonsguyhttp://commonsware.com/blog|http://twitter.com/commonsguy Android App Developer Books:http://commonsware.com/books -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to
[android-developers] Re: Service Process Vs background process
On Feb 17, 7:11 am, Sivaprakash sivaprakashshanmu...@gmail.com wrote: OK if you go through the following link http://developer.android.com/guide/topics/fundamentals.html Processes and lifecycles sectionthere are two things Service Process and Background Process, how they differ each other? - Siva The process descriptions at the bottom of that link are letting you know the order in which the OS will reclaim resources. Here's my rudimentary understanding: background process is something that is not currently visible or actively processing, the canonical example being an Activity whose onStop() has been called. Such processes can be killed by the OS when it needs to reclaim resources. service process is something that is not visible, but is currently processing and affecting the user experience. Think of playing music or monitoring location, for example. A Service (i.e. instantiation of the class Service) can and will be classified as all of those processes during its lifetime. Part of the confusion is that a service isn't necessarily running in a separate process from the Activity that instantiates it and launches it. -- You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to android-developers+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/android-developers?hl=en
[android-developers] Re: (Service == Process)?
Hi guys, thanks very much for your answers. Your answers and the link that I obviously missed helped me clear out these things. Patrick On Dec 1, 8:03 pm, Dianne Hackborn [EMAIL PROTECTED] wrote: On Mon, Dec 1, 2008 at 5:41 AM, patrick [EMAIL PROTECTED] wrote: - therefore an activity is a process - but from what I know a service uses another address space than the hosting activity If there is anything inhttp://code.google.com/android/intro/appmodel.htmlorthe other docs leading you to this conclusion, please let me know what that is so we can fix it. :) - how are AIDL IPC calls synchronized when they are different processes? There is a special driver in the kernel called binder that takes care of these IPCs. -- Dianne Hackborn Android framework engineer [EMAIL PROTECTED] Note: please don't send private questions to me, as I don't have time to provide private support. All such questions should be posted on public forums, where I and others can see and answer them. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~--~~~~--~~--~--~---
[android-developers] Re: (Service == Process)?
patrick wrote: I am a little confused about the difference between services and processes in Android. From what I understood: - each package may run as one process At minimum. A package might have more than one process, though that is discouraged. - therefore an activity is a process No, because a package may have more than one activity. - a service runs in the main thread of an activity (therefore it needs to run in the same process) If it is a local service, yes. Or, in your AndroidManifest.xml file, you could specify that the service is to run in another process. - but from what I know a service uses another address space than the hosting activity A local service shares the address space with anything else in that process, including, possibly, one or more activities. - because I don't know of another way in Linux to create a new virtual memory space than by using a new process I assume, that a service is actually a new process Only if you set it up that way in AndroidManifest.xml. And, again, this is discouraged. -- Mark Murphy (a Commons Guy) http://commonsware.com Android Training on the Ranch! -- Mar 16-20, 2009 http://www.bignerdranch.com/schedule.shtml --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~--~~~~--~~--~--~---
[android-developers] Re: (Service == Process)?
On Mon, Dec 1, 2008 at 5:41 AM, patrick [EMAIL PROTECTED] wrote: - therefore an activity is a process - but from what I know a service uses another address space than the hosting activity If there is anything in http://code.google.com/android/intro/appmodel.htmlor the other docs leading you to this conclusion, please let me know what that is so we can fix it. :) - how are AIDL IPC calls synchronized when they are different processes? There is a special driver in the kernel called binder that takes care of these IPCs. -- Dianne Hackborn Android framework engineer [EMAIL PROTECTED] Note: please don't send private questions to me, as I don't have time to provide private support. All such questions should be posted on public forums, where I and others can see and answer them. --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~--~~~~--~~--~--~---
