From 3f511a3e48c8348bb4eab2718956260a8fbda291 Mon Sep 17 00:00:00 2001 From: Arnaud Giersch Date: Thu, 1 Sep 2011 11:30:58 +0200 Subject: [PATCH] Fix random auto-deployment in integer mode. --- deployment.cpp | 42 ++++++++++++++++++------------------------ 1 file changed, 18 insertions(+), 24 deletions(-) diff --git a/deployment.cpp b/deployment.cpp index 2befb00..0b30423 100644 --- a/deployment.cpp +++ b/deployment.cpp @@ -64,34 +64,28 @@ void deployment_generator::distribute_load() std::transform(loads.begin(), loads.end(), loads.begin(), std::bind(std::multiplies(), _1, factor)); if (opt::integer_transfer) { - // round the loads - std::vector iloads(hosts.size()); - std::transform(loads.begin(), loads.end(), iloads.begin(), round); - // compute the differences between each load and its rounded value - std::vector diffs(hosts.size()); - std::transform(loads.begin(), loads.end(), iloads.begin(), - diffs.begin(), std::minus()); - // compute the absolute values of the diffs - std::vector adiffs(hosts.size()); - std::transform(diffs.begin(), diffs.end(), adiffs.begin(), fabs); - // find i, index of the element farthest from its rounded value + double iload; + double residue = 0.0; unsigned i; - i = std::max_element(adiffs.begin(), adiffs.end()) - adiffs.begin(); - // remove element i from diffs, and compute the residual part... - diffs[i] = diffs.back(); - diffs.pop_back(); - double residue = std::accumulate(diffs.begin(), diffs.end(), 0.0); - // ... and compute element i (rounded to avoid numerical errors) - iloads[i] = fabs(round(loads[i] + residue)); + for (i = 0 ; i < hosts.size() - 1; ++i) { + if (residue < 0.0) + iload = floor(loads[i]); + else if (residue > 0.0) + iload = ceil(loads[i]); + else // residue == 0.0 + iload = round(loads[i]); + residue += (loads[i] - iload); + loads[i] = iload; + } + // abs(round(...)) to avoid rounding errors, or a value of -0 + iload = abs(round(loads[i] + residue)); // i == hosts.size() - 1 + loads[i] = iload; // final sanity check xbt_assert(opt::auto_depl::load == - std::accumulate(iloads.begin(), iloads.end(), 0.0)); - for (unsigned i = 0 ; i < hosts.size() ; ++i) - set_load(i, iloads[i]); - } else { - for (unsigned i = 0 ; i < hosts.size() ; ++i) - set_load(i, loads[i]); + std::accumulate(loads.begin(), loads.end(), 0.0)); } + for (unsigned i = 0 ; i < hosts.size() ; ++i) + set_load(i, loads[i]); } void deployment_generator::deploy() -- 2.39.5