[Bug c/12695] New: Unusually long link times for large executables on x86_64

[tbennett at cray dot com]

PLEASE REPLY TO gcc-bugzilla@gcc.gnu.org ONLY, *NOT* gcc-bugs@gcc.gnu.org.

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12695

           Summary: Unusually long link times for large executables on
                    x86_64
           Product: gcc
           Version: 3.3.2
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: c
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: tbennett at cray dot com
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: x86_64-unknown-linux-gnu
  GCC host triplet: x86_64-unknown-linux-gnu
GCC target triplet: x86_64-unknown-linux-gnu

I am getting long link times for large executables when running GCC/3.3.2 on an
x86_64 Opteron processor.  I have been comparing the performance to an
alphaev68-unknown-linux-gnu machine also running GCC/3.3.2.

For a 30MB executable, the Opteron takes 5 minutes to link vs. a couple seconds
on the alpha.

For a 100MB executable, the Opteron takes nearly 2 hours while still only a few
seconds on the Alpha processor.

Both machines were configured to compile 64-bit executables.  Also, both
machines were only servicing this single task during the benchmark and I/O was
on a local mounted disc.  In all other applications, including compilation, the
Opteron is much faster than the Alpha system.