rtld optimizations

[Joerg Sonnenberger]

On Thu, Jan 27, 2011 at 06:24:18PM -0500, Alexander Kabaev wrote:
> For starters, the number of libraries given binary is linked too is
> completely and utterly irrelevant :) The change NetBSD guys claims to
> revolutionize his application startup times only applies to programs
> that dlopen (read - load dynamically) libraries with long largely
> identical dependency chains and calls dlsym on them many, many
> thousand times. I do not think you will find any real app out there
> that fits this description close enough to actually demonstrate the
> effect of the change that is distinguishable from the statistical noise.
> Pressing ^C certainly not precise enough for that.

(1) The program itself needs to have a large enough number of linked
libraries.

(2) The program needs to dlopen() modules.

(3) The program needs to search for missing symbols often enough.

>From memory, the real world example that fulfilled all three cases was
Evolution. (1) and (2) are pretty typical though.

Joerg