Re: [GIT PULL] kdbus for 4.1-rc1

Greg Kroah-Hartman
2015-04-15T18:37:21Z

On Wed, Apr 15, 2015 at 11:28:58AM -0700, Linus Torvalds wrote:
> On Wed, Apr 15, 2015 at 11:18 AM, Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
> >
> > I've seen this claimed, but I have never seen any actual numbers. What
> > speeds up? By how much? is it actually measurable?
>
> And just to clarify: by "what speeds up, and by how much", I do _not_
> mean "sending a dbus message speeds up by 10x and avoids context
> switches". I've seen _those_ numbers. But does it actually matter?
>
> It was more of a "there are thousands of dbus messages during boot,
> but can you actually measure the speedup?" question. That's the kind
> of numbers I've not seen.

Someone from BMW did the testing on one of their car systems a while ago
and posted some numbers, it was a factor of 10 faster. I'll try to dig
it up, but it was burried in a powerpoint presentation, so it might be
hard to find, give me a day.

thanks,

greg k-h