1 Reply Latest reply on Sep 4, 2008 7:30 AM by rahulgarg

    calExtGetCounter : Negative values for cache hit rates??

    rahulgarg
      Getting weird values from cache hit rate counters

      I am trying to determine the cache hit rate on on one of my kernels. To create, begin, end, get and destroy counters I am following the example in perf_counters.cpp.
      However, when I get the counter value (the counter being CAL_COUNTER_CACHE_HIT_RATE), I get a negative value in some cases.

      Any pointers to what might be wrong?

        • calExtGetCounter : Negative values for cache hit rates??
          rahulgarg
          Some info :
          a) I am running the same kernel multiple times inside a loop. Each time its run with different parameters. I am basically trying to find out the cache hit rate as a function of the kernel parameters.
          b) In some iterations I get a postivie and mostly expected hit rate. In other iterations, the hit rates are negative. Moreover the results are not random. I get the same results on every run.
          c) Card : 3850. OS : Tested under XP + Catalyst 8.7 as well as OpenSuse 32-bit + Catalyst 8.6. In both cases results are the same.