[Linaro-mm-sig] Memory Management Discussion

[Jesse Barnes]

On Thu, 21 Apr 2011 11:50:25 -0700
Rebecca Schultz Zavin <rebecca at android.com> wrote:

> On Thu, Apr 21, 2011 at 8:14 AM, Jesse Barnes <jbarnes at virtuousgeek.org>wrote:
> 
> > On Thu, 21 Apr 2011 16:09:46 +0100
> > Tom Cooksey <Tom.Cooksey at arm.com> wrote:
> >
> > > > Client apps also have to worry about the fd count, since depending on
> > > > the app and object caching policy it's very easy to get over 1024
> > > > objects.  But the solutions above may work for that case as well; I
> > > > don't expect many apps rely on select(), and those that do can fairly
> > > > easily be converted.
> > >
> > > Though presumably not if you only have an fd for buffers you want to
> > > share with another process or device? I think the common case is you
> > > don't want to share a texture or command buffer or whatever with
> > > another process, so most of the objects don't need an fd?
> >
> > Oh sure, if you don't actually allocate fds for the objects, then
> > there's no issue.  But I think the ION proposal created fds for mapped
> > objects as well?  That count could get pretty high...
> >
> 
> That's lazy programmer (me) wanting to be able to mmap at an offset and not
> wanting to implement all of mmap in an ioctl.  Anyway I think you can map
> them and then close them, wouldn't that allow you to recycle the fd?

Yeah, I think that would work fine.

-- 
Jesse Barnes, Intel Open Source Technology Center