Re: Sdbusplus-based Shared Library

[Andrew Jeffery <andrew@aj.id.au>]

On Tue, 20 Mar 2018, at 06:03, Patrick Venture wrote:
> On Mon, Mar 19, 2018 at 11:24 AM, Tanous, Ed <ed.tanous@intel.com> wrote:
> > Have you tried prototyping to see how much space you'll save?  I suspect it won't be a lot for a few reasons.
> >
> > 1. A lot of sdbusplus is template instantiations, and unless we forward declare a number of base template instantiations for use in the shared library, most of the application code will end up in the binary anyway.
> > 2. Sdbus calls into libsystemd, which is already a shared library.
> > 3. The filesystem is already compressed, so I suspect that any duplicated methods that aren't inlined will have the same binary code pattern and get duplicated by the squashfs filesystem.
> >
> > Those are all the reasons why I haven't really looked into it for the dbus stuff;  I can't speak to the timer stuff, but I suspect the wins in size there are going to be small.
> >
> > Normal disclaimer, on this specific library, I haven't prototyped anything, just done back of the napkin guesses, so I could very easily be missing something here.
> >
> 
> So my thinking wasn't about reducing size of the binary but rather
> reducing the toil of maintaining multiple implementations of the same
> code.
> 

I'm on board with this idea. There are a bunch of utility classes defined for RAII that are (were) used in phosphor-mboxd that would be much better off defined in some library where they can be reused.

Has anyone looked at this beyond what's in the thread?

Cheers,

Andrew