Profesores

problems using stl in implicit model

Hello,

I am writing this very simple program using implicit offload model. wherein I make use of cilk_plus lib. I run into trouble when I do the following, my code doesn't run, can anyone please help me understand what I am doing incorrect here,

I am not including the definitions because when I do so somehow my message gets spammed. but if you look at the class body it is very straightforward.

#include <iostream>
#include <cilk/cilk.h>

documentation and information about power readings from the Xeon Phi3

I want to get power readings from the mic and I found that power is updated here (/sys/class/micras/power ) around every 5 milliseconds. I found some vague description of these numbers on some websites, and I didnt find anything useful. I would like to get more information on the numbers and details on what parts of the MIC are they representing. I found some descriptions such as win0 and win 1, and if these descriptions are correct what's win 0,win 1 etc?

How to tell ICC to vectorize basic blocks?

Please note, that this is a cross post from StackOverflow: http://stackoverflow.com/questions/21135281/how-to-make-the-intel-c-compiler-icc-vectorize-basic-blocks

I am currently using icc (version 13.1.0.146) to compile C programs running in native mode on the Intel Xeon Phi coprocessor.

Consider the following two code fragments:

adding _mm_delay actually make the code run faster?

I experience an strange situation when I am optimizing some mic code.

The new optimized code runs faster, measured using __rdtsc().  But the new run time is actually slower than the old code!  The code, by the way, is not a loop, and my co-worker found sometimes loop runs faster then unrolled loop.  This lead me to speculate that icache may be starved due to too may vector operation, so I added _mm_delay_32(n) to let it recover.

This is the result I got

no delay added -- run time 6.65

delay(4) -- run time 6.63

delay(8) -- run time 6.60

Suscribirse a Profesores