Re: [patch] Eliminate quadratic slow-down on number of solibs (part 2).

[Paul Pluzhnikov <ppluzhnikov at google dot com>]

On Fri, May 1, 2009 at 3:16 PM, Paul Pluzhnikov <ppluzhnikov@google.com> wrote:

> This is the patch to eliminate repeated iteration over the same objfile
> looking for Objective-C methods, as Tom suggested here:
> ?http://sourceware.org/ml/gdb-patches/2009-04/msg00551.html

Even after the two patches above, there is still some repeated
and unnecessary setting and resetting of the breakpoints as each
solib is added :-(

Attached is an alternative patch which subsumes the other two,
and kills additional 15% of wasted CPU time.

It feels like a hack, but I don't see how to achieve the same
result in a cleaner way :-(

Timing on my 2780-solib test (just running ldd on that takes 15s):

time gdb -ex 'break main' -ex run -ex kill -ex quit request_test

=== current CVS Head ===
real    11m16.762s
user    11m5.530s
sys     0m9.697s

=== with attached patch ===
real    2m43.595s
user    2m33.350s
sys     0m9.353s

Tested on Linux/x86_64 without regressions.

Comments?
--
Paul Pluzhnikov

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