X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/1847d1441271d076b3de449c8853031ea208ce8f..86a55422a209c7793c7f9430c67db0308bdfa474:/src/smpi/internals/smpi_bench.cpp diff --git a/src/smpi/internals/smpi_bench.cpp b/src/smpi/internals/smpi_bench.cpp index 107430771d..5b05ac59db 100644 --- a/src/smpi/internals/smpi_bench.cpp +++ b/src/smpi/internals/smpi_bench.cpp @@ -264,7 +264,18 @@ unsigned long long smpi_rastro_timestamp () } /* ****************************** Functions related to the SMPI_SAMPLE_ macros ************************************/ -typedef struct { +namespace { +class SampleLocation : public std::string { +public: + SampleLocation(bool global, const char* file, int line) : std::string(std::string(file) + ":" + std::to_string(line)) + { + if (not global) + this->append(":" + std::to_string(smpi_process()->index())); + } +}; + +class LocalData { +public: double threshold; /* maximal stderr requested (if positive) */ double relstderr; /* observed stderr so far */ double mean; /* mean of benched times, to be used if the block is disabled */ @@ -272,94 +283,85 @@ typedef struct { double sum_pow2; /* sum of the square of the benched times (to compute the stderr) */ int iters; /* amount of requested iterations */ int count; /* amount of iterations done so far */ - int benching; /* 1: we are benchmarking; 0: we have enough data, no bench anymore */ -} local_data_t; - -std::unordered_map samples; /* Allocated on first use */ + bool benching; /* true: we are benchmarking; false: we have enough data, no bench anymore */ -static std::string sample_location(int global, const char* file, int line) -{ - if (global) { - return std::string(file) + ":" + std::to_string(line); - } else { - return std::string(file) + ":" + std::to_string(line) + ":" + std::to_string(smpi_process()->index()); - } + bool need_more_benchs() const; +}; } -static int sample_enough_benchs(local_data_t *data) { - int res = data->count >= data->iters; - if (data->threshold>0.0) { - if (data->count <2) - res = 0; // not enough data - if (data->relstderr > data->threshold) - res = 0; // stderr too high yet - } +std::unordered_map> samples; + +bool LocalData::need_more_benchs() const +{ + bool res = (count < iters) || (threshold > 0.0 && (count < 2 || // not enough data + relstderr > threshold // stderr too high yet + )); XBT_DEBUG("%s (count:%d iter:%d stderr:%f thres:%f mean:%fs)", - (res?"enough benchs":"need more data"), data->count, data->iters, data->relstderr, data->threshold, data->mean); + (res ? "need more data" : "enough benchs"), count, iters, relstderr, threshold, mean); return res; } void smpi_sample_1(int global, const char *file, int line, int iters, double threshold) { - std::string loc = sample_location(global, file, line); + SampleLocation loc(global, file, line); smpi_bench_end(); /* Take time from previous, unrelated computation into account */ smpi_process()->set_sampling(1); - auto ld = samples.find(loc); - local_data_t* data; - if (ld == samples.end()) { - xbt_assert(threshold>0 || iters>0, - "You should provide either a positive amount of iterations to bench, or a positive maximal stderr (or both)"); - data = static_cast(xbt_new(local_data_t, 1)); - data->count = 0; - data->sum = 0.0; - data->sum_pow2 = 0.0; - data->iters = iters; - data->threshold = threshold; - data->benching = 1; // If we have no data, we need at least one - data->mean = 0; - samples[loc] = data; + auto insert = samples.emplace(loc, LocalData{ + threshold, // threshold + 0.0, // relstderr + 0.0, // mean + 0.0, // sum + 0.0, // sum_pow2 + iters, // iters + 0, // count + true // benching (if we have no data, we need at least one) + }); + LocalData& data = insert.first->second; + if (insert.second) { XBT_DEBUG("XXXXX First time ever on benched nest %s.", loc.c_str()); + xbt_assert(threshold > 0 || iters > 0, + "You should provide either a positive amount of iterations to bench, or a positive maximal stderr (or both)"); } else { - data = ld->second; - if (data->iters != iters || data->threshold != threshold) { + if (data.iters != iters || data.threshold != threshold) { XBT_ERROR("Asked to bench block %s with different settings %d, %f is not %d, %f. " "How did you manage to give two numbers at the same line??", - loc.c_str(), data->iters, data->threshold, iters, threshold); + loc.c_str(), data.iters, data.threshold, iters, threshold); THROW_IMPOSSIBLE; } // if we already have some data, check whether sample_2 should get one more bench or whether it should emulate // the computation instead - data->benching = (sample_enough_benchs(data) == 0); + data.benching = data.need_more_benchs(); XBT_DEBUG("XXXX Re-entering the benched nest %s. %s", loc.c_str(), - (data->benching ? "more benching needed" : "we have enough data, skip computes")); + (data.benching ? "more benching needed" : "we have enough data, skip computes")); } } int smpi_sample_2(int global, const char *file, int line) { - std::string loc = sample_location(global, file, line); + SampleLocation loc(global, file, line); int res; - xbt_assert(not samples.empty(), - "Y U NO use SMPI_SAMPLE_* macros? Stop messing directly with smpi_sample_* functions!"); - local_data_t* data = samples.at(loc); XBT_DEBUG("sample2 %s", loc.c_str()); + auto sample = samples.find(loc); + if (sample == samples.end()) + xbt_die("Y U NO use SMPI_SAMPLE_* macros? Stop messing directly with smpi_sample_* functions!"); + LocalData& data = sample->second; - if (data->benching==1) { + if (data.benching) { // we need to run a new bench XBT_DEBUG("benchmarking: count:%d iter:%d stderr:%f thres:%f; mean:%f", - data->count, data->iters, data->relstderr, data->threshold, data->mean); + data.count, data.iters, data.relstderr, data.threshold, data.mean); res = 1; } else { // Enough data, no more bench (either we got enough data from previous visits to this benched nest, or we just //ran one bench and need to bail out now that our job is done). Just sleep instead XBT_DEBUG("No benchmark (either no need, or just ran one): count >= iter (%d >= %d) or stderrcount, data->iters, data->relstderr, data->threshold, data->mean); - smpi_execute(data->mean); + data.count, data.iters, data.relstderr, data.threshold, data.mean); + smpi_execute(data.mean); smpi_process()->set_sampling(0); res = 0; // prepare to capture future, unrelated computations } @@ -369,36 +371,37 @@ int smpi_sample_2(int global, const char *file, int line) void smpi_sample_3(int global, const char *file, int line) { - std::string loc = sample_location(global, file, line); + SampleLocation loc(global, file, line); - xbt_assert(not samples.empty(), - "Y U NO use SMPI_SAMPLE_* macros? Stop messing directly with smpi_sample_* functions!"); - local_data_t* data = samples.at(loc); XBT_DEBUG("sample3 %s", loc.c_str()); + auto sample = samples.find(loc); + if (sample == samples.end()) + xbt_die("Y U NO use SMPI_SAMPLE_* macros? Stop messing directly with smpi_sample_* functions!"); + LocalData& data = sample->second; - if (data->benching==0) + if (not data.benching) THROW_IMPOSSIBLE; // ok, benchmarking this loop is over xbt_os_threadtimer_stop(smpi_process()->timer()); // update the stats - data->count++; - double sample = xbt_os_timer_elapsed(smpi_process()->timer()); - data->sum += sample; - data->sum_pow2 += sample * sample; - double n = static_cast(data->count); - data->mean = data->sum / n; - data->relstderr = sqrt((data->sum_pow2 / n - data->mean * data->mean) / n) / data->mean; - if (sample_enough_benchs(data)==0) { - data->mean = sample; // Still in benching process; We want sample_2 to simulate the exact time of this loop + data.count++; + double period = xbt_os_timer_elapsed(smpi_process()->timer()); + data.sum += period; + data.sum_pow2 += period * period; + double n = static_cast(data.count); + data.mean = data.sum / n; + data.relstderr = sqrt((data.sum_pow2 / n - data.mean * data.mean) / n) / data.mean; + if (data.need_more_benchs()) { + data.mean = period; // Still in benching process; We want sample_2 to simulate the exact time of this loop // occurrence before leaving, not the mean over the history } - XBT_DEBUG("Average mean after %d steps is %f, relative standard error is %f (sample was %f)", data->count, - data->mean, data->relstderr, sample); + XBT_DEBUG("Average mean after %d steps is %f, relative standard error is %f (sample was %f)", + data.count, data.mean, data.relstderr, period); // That's enough for now, prevent sample_2 to run the same code over and over - data->benching = 0; + data.benching = false; } extern "C" { /** These functions will be called from the user code **/ @@ -432,6 +435,5 @@ void smpi_trace_set_call_location__(const char* file, int* line) void smpi_bench_destroy() { - for (auto const& elm : samples) - xbt_free(elm.second); + samples.clear(); }