Recent Features
| |||||||||||||
GCC celebrates 25 years with the 4.7.0 releaseGCC celebrates 25 years with the 4.7.0 releasePosted Mar 23, 2012 9:08 UTC (Fri) by engla (guest, #47454)In reply to: GCC celebrates 25 years with the 4.7.0 release by PaXTeam Parent article: GCC celebrates 25 years with the 4.7.0 release
Any performance improvements with LTO?
(Log in to post comments)
GCC celebrates 25 years with the 4.7.0 release Posted Mar 23, 2012 10:11 UTC (Fri) by PaXTeam (subscriber, #24616) [Link]
i didn't do any benchmarks so i can't tell. note also that the above kernels don't have the exact same config due to some yet-to-be-fixed deficiences with LTO or clang (e.g., the LTO kernel above didn't have KALLSYMS/KPROBES/FUNCTION_TRACER enabled and the clang one didn't use the PaX gcc plugins for obvious reasons).
GCC celebrates 25 years with the 4.7.0 release Posted Mar 25, 2012 1:07 UTC (Sun) by nix (subscriber, #2304) [Link]
I frankly doubt you'd see enormous improvements in non-pathological benchmarks anyway, because the kernel is not the predominant consumer of CPU time in most benchmarks, and LTO will do nothing to improve locality of reference or any of the heaps of algorithmic things which a kernel has to deal with and which really do take time. You'd probably see an improvement from reduction in icache pressure though, but I have no idea how big it might be. Probably minimal, but one can hope.
As always, the numbers will tell.
|
|||||||||||||