Like I said, it is part of a much lower-level part of the IPC system, so independent of what you are doing at the level of marshalling a bitmap across processes. I don't have the exact number off-hand, but if you are thinking about this as a limit on how big a bitmap you can send, you are probably going to have other problems (such as multiple local allocations to hold the data and the copying overhead) before that comes into play. As a rule I would avoid sending anything more than 100K across processes, and really try to keep that far less... and though the current impl does allow for far more, as I said other performance issues will come into play and that memory is used for all active transactions delivering data or replies to the process.
Also, this memory is not shared between two processes, it is shared between the kernel and the process it is delivering data to. On Tue, May 26, 2009 at 5:22 PM, George <[email protected]> wrote: > > Thanks Dianne. > > Is the shared memory size fixed? If yes, what is typically the size? > > On May 26, 4:59 pm, Dianne Hackborn <[email protected]> wrote: > > Depends on how you define this. It makes a copy of the bitmap. The > > underlying Binder IPC mechanism uses shared memory to deliver data, but > this > > isn't happening up at the Bitmap level so you have at least a couple > copies > > of the data being made. > > > > In general, please avoid sending anything except icon size bitmaps across > > processes. > > > > On Tue, May 26, 2009 at 4:49 PM, George <[email protected]> wrote: > > > > > When I pass a Bitmap using the Binder Remote service mechanism, does > > > the internal implementation of writeToParcel/createFromParcel of the > > > Bitmap class use shared memory? > > > > -- > > 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, 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. > > > -- 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, 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 [email protected] 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 -~----------~----~----~----~------~----~------~--~---
