Nathan Hjelm writes:
> I wouldn't be concerned about the usage of gettimeofday in scif. Those
> calls are disabled by default and are for internal measurements
> only. Nothing to do with Wtime.
That was the point -- clock_gettime doesn't anywhere relevant.
George Bosilca writes:
> In opal/mca/linux/timer_linux_component.c. The timer is a special component
> which is statically included during the build process (via
> the MCA_timer_IMPLEMENTATION_HEADER define in opal/mca/timer/base/base.h
> line 48). Thus the symbol should appear directly in the li
I wrote:
> Are you talking about different source?
On further investigation it looks so -- the development source does
feature clock_gettime, but the release doesn't. Back to LD_PRELOAD...
Dave,
fwiw, on v1.10, we likely use the number of cycles / cpu freq.
see opal_sys_timer_get_cycles in
https://github.com/open-mpi/ompi-release/blob/v1.10/opal/include/opal/sys/amd64/timer.h
I cannot remember whether this is a monotonic timer.
(e.g. MPI_Wtime() invoked on a given cpu is always lo
git blame reports that the gettime patch is in master for the last 1 1/2
years (Nov 2014). Here is an untested patch (cherrypicked 00300f464d plus
few changes).
george.
On Wed, Apr 6, 2016 at 9:32 AM, Gilles Gouaillardet <
gilles.gouaillar...@gmail.com> wrote:
> Dave,
>
> fwiw, on v1.10, w
Gilles Gouaillardet writes:
> Dave,
>
> fwiw, on v1.10, we likely use the number of cycles / cpu freq.
That would be a horribly broken means of timing. gettimeofday is
actually called under mpi_wtime, as ompi_info claims.
> see opal_sys_timer_get_cycles in
> https://github.com/open-mpi/ompi-re
Dave,
i checked again, and yes, v1.10 uses gettimeofday() in MPI_Wtime() on linux.
native timers are only used in aix and solaris
$ grep -R OPAL_TIMER_USEC_NATIVE opal/mca/timer
opal/mca/timer/aix/timer_aix.h:#define OPAL_TIMER_USEC_NATIVE 1
opal/mca/timer/altix/timer_altix.h:#define OPAL_TIMER
