mirror of
https://github.com/ceres-solver/ceres-solver.git
synced 2026-08-29 08:34:37 +08:00
Mike Vitus
5d8b494557
With the addition of C++11 support we can simplify the parallel for code by removing the ifdef branching. Converts coordinate_descent_minimizer.cc to use the thread_id ParallelFor API. Tested by building with OpenMP, C++11 threads, TBB, and no threads. All tests pass. Also compared timing via the bundle adjuster. ./bin/bundle_adjuster --input=../problem-744-543562-pre.txt With OpenMP num_threads=8 Head: Time (in seconds): Residual only evaluation 0.807753 (5) Jacobian & residual evaluation 4.489404 (6) Linear solver 41.826481 (5) Minimizer 50.745857 Total 73.294424 CL: Time (in seconds): Residual only evaluation 0.970483 (5) Jacobian & residual evaluation 4.647438 (6) Linear solver 41.781892 (5) Minimizer 50.848904 Total 73.089983 With OpenMP num_threads=1 HEAD: Time (in seconds): Residual only evaluation 2.990246 (5) Jacobian & residual evaluation 14.132090 (6) Linear solver 79.631951 (5) Minimizer 100.281847 Total 122.946267 CL: Time (in seconds): Residual only evaluation 3.075178 (5) Jacobian & residual evaluation 13.966451 (6) Linear solver 77.005441 (5) Minimizer 97.568712 Total 120.410454 Change-Id: I1857d7943073be7465b6c6476bf46ab11c5475a3
84 lines
3.1 KiB
C++
84 lines
3.1 KiB
C++
// Ceres Solver - A fast non-linear least squares minimizer
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// Copyright 2018 Google Inc. All rights reserved.
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// http://ceres-solver.org/
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are met:
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//
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// * Redistributions of source code must retain the above copyright notice,
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// this list of conditions and the following disclaimer.
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// * Redistributions in binary form must reproduce the above copyright notice,
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// this list of conditions and the following disclaimer in the documentation
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// and/or other materials provided with the distribution.
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// * Neither the name of Google Inc. nor the names of its contributors may be
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// used to endorse or promote products derived from this software without
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// specific prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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// POSSIBILITY OF SUCH DAMAGE.
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//
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// Author: vitus@google.com (Michael Vitus)
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// This include must come before any #ifndef check on Ceres compile options.
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#include "ceres/internal/port.h"
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#if !(defined(CERES_USE_TBB) || defined(CERES_USE_CXX11_THREADS))
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#include "ceres/parallel_for.h"
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#include "ceres/scoped_thread_token.h"
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#include "ceres/thread_token_provider.h"
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#include "glog/logging.h"
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namespace ceres {
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namespace internal {
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void ParallelFor(ContextImpl* context,
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int start,
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int end,
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int num_threads,
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const std::function<void(int)>& function) {
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CHECK_GT(num_threads, 0);
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CHECK(context != NULL);
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if (end <= start) {
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return;
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}
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#ifdef CERES_USE_OPENMP
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#pragma omp parallel for num_threads(num_threads) \
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schedule(dynamic) if (num_threads > 1)
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#endif // CERES_USE_OPENMP
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for (int i = start; i < end; ++i) {
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function(i);
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}
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}
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void ParallelFor(ContextImpl* context,
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int start,
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int end,
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int num_threads,
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const std::function<void(int thread_id, int i)>& function) {
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CHECK(context != NULL);
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ThreadTokenProvider thread_token_provider(num_threads);
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ParallelFor(context, start, end, num_threads, [&](int i) {
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const ScopedThreadToken scoped_thread_token(&thread_token_provider);
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const int thread_id = scoped_thread_token.token();
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function(thread_id, i);
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});
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}
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} // namespace internal
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} // namespace ceres
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#endif // !(defined(CERES_USE_TBB) || defined(CERES_USE_CXX11_THREADS))
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