• 2019 Update 3
  • 03/07/2019
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This timer is provided by the MPI implementation. In general this is simply a wrapper around
gettimeofday()
and then using it instead of
gettimeofday()
only has disadvantages: with
gettimeofday()
Intel® Trace Collector knows that processes running on the same node share the same clock and thus does not synchronize between them. The same information cannot be obtained through the MPI API and thus Intel® Trace Collector is conservative and assumes that clock synchronization is needed. This can be overridden with the
SYNCED-HOST
configuration option. Another disadvantage is increased overhead and potentially implementation errors in MPI.
If the MPI has access to a better timer source (for example a global clock in the underlying communication hardware), then using this timer would be advantageous.

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804