DragonFly On-Line Manual Pages

Search: Section:  

hwloc_distances_s(3)       Hardware Locality (hwloc)      hwloc_distances_s(3)


NAME

       hwloc_distances_s -


SYNOPSIS

       #include <hwloc.h>

   Data Fields
       unsigned relative_depth
       unsigned nbobjs
       float * latency
       float latency_max
       float latency_base

Detailed Description
       Distances between objects.

       One object may contain a distance structure describing distances
       between all its descendants at a given relative depth. If the
       containing object is the root object of the topology, then the
       distances are available for all objects in the machine.

       If the latency pointer is not NULL, the pointed array contains memory
       latencies (non-zero values), see below.

       In the future, some other types of distances may be considered. In
       these cases, latency may be NULL.

Field Documentation
   float* hwloc_distances_s::latency
       Matrix of latencies between objects, stored as a one-dimension array.
       May be NULL if the distances considered here are not latencies. Unless
       defined by the user, this currently contains latencies between NUMA
       nodes (as reported in the System Locality Distance Information Table
       (SLIT) in the ACPI specification), which may or may not be accurate. It
       corresponds to the latency for accessing the memory of one node from a
       core in another node.

       Values are normalized to get 1.0 as the minimal value in the matrix.
       Latency from i-th to j-th object is stored in slot i*nbobjs+j.

   float hwloc_distances_s::latency_base
       The multiplier that should be applied to latency matrix to retrieve the
       original OS-provided latencies. Usually 10 on Linux since ACPI SLIT
       uses 10 for local latency.

   float hwloc_distances_s::latency_max
       The maximal value in the latency matrix.

   unsigned hwloc_distances_s::nbobjs
       Number of objects considered in the matrix. It is the number of
       descendant objects at relative_depth below the containing object. It
       corresponds to the result of hwloc_get_nbobjs_inside_cpuset_by_depth().

   unsigned hwloc_distances_s::relative_depth
       Relative depth of the considered objects below the object containing
       this distance information.

Author
       Generated automatically by Doxygen for Hardware Locality (hwloc) from
       the source code.

Version 1.11.1                  Thu Oct 15 2015           hwloc_distances_s(3)

Search: Section: