Re: [Libunwind-devel] Performance issue with tdep_get_elf_image()

[David Mosberger-Tang]

Ah, I'd forgotten about that!  Good.

  --david

On 6/3/08, Arun Sharma <address@hidden> wrote:
> On Sat, May 31, 2008 at 7:16 AM, David Mosberger-Tang
>  <address@hidden> wrote:
>  > Caching would improve performance greatly.  The ia64 version of
>  > libunwind has this implemented, but not the DWARF-based version (yet).
>
>
> There is such a cache in dwarf/Gparser.c:get_rs_cache().
>
>  But I've tested it only on x86. Perhaps it's not getting enabled on
>  ARM for some reason?
>
>  On x86_64:
>
>  $ tests/Lperf-simple
>  unw_getcontext : cold avg=  259.876 nsec, warm avg=  209.808 nsec
>  unw_init_local : cold avg=  309.944 nsec, warm avg=  169.277 nsec
>  no cache        : unw_step : 1st=10104.406 min= 1750.674 avg= 1812.264 nsec
>  global cache    : unw_step : 1st= 7665.725 min=  122.615 avg=  133.057 nsec
>  per-thread cache: unw_step : 1st= 6103.516 min=  122.615 avg=  133.020 nsec
>
>
>   -Arun
>


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