Support for multi threading in various parts of the sampling algorithm

.gitattributes

@@ -0,0 +1,16 @@
+* text=auto
+
+*.c   text eol=lf
+*.h   text eol=lf
+*.cc  text eol=lf
+*.cuh text eol=lf
+*.cu  text eol=lf
+*.py  text eol=lf
+*.txt text eol=lf
+*.R   text eol=lf
+
+*.sh text eol=lf
+*.ac text eol=lf
+
+*.md  text eol=lf
+*.csv text eol=lf

.github/workflows/cpp-test.yml

@@ -56,6 +56,12 @@ jobs:
       shell: bash
       run: |
         echo "build-output-dir=${{ github.workspace }}/build" >> "$GITHUB_OUTPUT"
+
+    - name: Set up dependencies (linux clang)
+      # Set up openMP on ubuntu-latest with clang compiler toolset (doesn't ship with the compiler suite like GCC and MSVC)
+      if: matrix.os == 'ubuntu-latest' && matrix.cpp_compiler == 'clang++'
+      run: | 
+        sudo apt-get update && sudo apt-get install -y libomp-dev
 
     - name: Configure CMake
       # Configure CMake in a 'build' subdirectory. `CMAKE_BUILD_TYPE` is only required if you are using a single-configuration generator such as make.
@@ -69,6 +75,7 @@ jobs:
         -DUSE_SANITIZER=OFF
         -DBUILD_TEST=ON
         -DBUILD_DEBUG_TARGETS=OFF
+        -DUSE_OPENMP=ON
         -S ${{ github.workspace }}
 
     - name: Build

.github/workflows/pypi-wheels.yml

@@ -21,26 +21,37 @@ jobs:
         include:
           - os: ubuntu-latest
             cibw_archs: "x86_64"
+            macos_deployment_target: "10.13" # Unused, just setting the variable as a placeholder
           - os: ubuntu-24.04-arm
             cibw_archs: "aarch64"
+            macos_deployment_target: "10.13" # Unused, just setting the variable as a placeholder
           - os: windows-latest
             cibw_archs: "auto64"
+            macos_deployment_target: "10.13" # Unused, just setting the variable as a placeholder
           - os: macos-13
             cibw_archs: "x86_64"
+            macos_deployment_target: "13.0"
           - os: macos-14
             cibw_archs: "arm64"
+            macos_deployment_target: "14.0"
 
     steps:
       - uses: actions/checkout@v4
         with:
           submodules: 'recursive'
+
+      - name: Set up openmp (macos)
+        # Set up openMP on MacOS since it doesn't ship with the apple clang compiler suite
+        if: matrix.os == 'macos-13' || matrix.os == 'macos-14'
+        run: | 
+          brew install libomp
 
       - name: Build wheels
         uses: pypa/cibuildwheel@v2.23.2
         env:
           CIBW_SKIP: "pp* *-musllinux_* *-win32"
           CIBW_ARCHS: ${{ matrix.cibw_archs }}
-          MACOSX_DEPLOYMENT_TARGET: "10.13"
+          MACOSX_DEPLOYMENT_TARGET: ${{ matrix.macos_deployment_target }}
 
       - uses: actions/upload-artifact@v4
         with:

.github/workflows/python-test.yml

@@ -30,6 +30,12 @@ jobs:
       with:
         python-version: "3.10"
         cache: "pip"
+
+    - name: Set up openmp (macos)
+      # Set up openMP on MacOS since it doesn't ship with the apple clang compiler suite
+      if: matrix.os == 'macos-latest'
+      run: | 
+        brew install libomp
 
     - name: Install Package with Relevant Dependencies
       run: |

.github/workflows/r-test.yml

@@ -22,6 +22,11 @@ jobs:
         os: [ubuntu-latest, windows-latest, macos-latest]
 
     steps:
+      - name: Prevent conversion of line endings on Windows
+        if: startsWith(matrix.os, 'windows')
+        shell: pwsh
+        run: git config --global core.autocrlf false
+
       - uses: actions/checkout@v4
         with:
           submodules: 'recursive'

.github/workflows/regression-test.yml

@@ -0,0 +1,50 @@
+on:
+  workflow_dispatch:
+
+name: Running stochtree on benchmark datasets
+
+jobs:
+  stochtree_r_bart:
+    name: stochtree-r-bart-regression-test
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout stochtree repo
+        uses: actions/checkout@v4
+        with:
+          submodules: 'recursive'
+
+      - name: Setup pandoc
+        uses: r-lib/actions/setup-pandoc@v2
+
+      - name: Setup R
+        uses: r-lib/actions/setup-r@v2
+        with:
+          use-public-rspm: true
+
+      - name: Create a properly formatted version of the stochtree R package in a subfolder
+        run: |
+          Rscript cran-bootstrap.R 0 0 1
+
+      - name: Setup R dependencies
+        uses: r-lib/actions/setup-r-dependencies@v2
+        with:
+          extra-packages: any::testthat, any::decor, local::stochtree_cran
+
+      - name: Create output directory for regression test results
+        run: |
+          mkdir -p tools/regression/stochtree_bart_r_results
+
+      - name: Run the regression test benchmark suite
+        run: |
+          Rscript tools/regression/regression_test_dispatch_bart.R
+
+      - name: Collate and analyze regression test results
+        run: |
+          Rscript tools/regression/regression_test_analysis_bart.R
+
+      - name: Store benchmark test results as an artifact of the run
+        uses: actions/upload-artifact@v4
+        with:
+          name: stochtree-r-bart-summary
+          path: tools/regression/stochtree_bart_r_results/stochtree_bart_r_summary.csv

.gitignore

@@ -70,6 +70,11 @@ po/*~
 # RStudio Connect folder
 rsconnect/
 
+# Configuration files generated by R build
+config.status
+config.log
+src/Makevars
+
 ## Python gitignore
 
 # Byte-compiled / optimized / DLL files

CMakeLists.txt

@@ -1,6 +1,8 @@
 # Build options
-option(USE_DEBUG "Set to ON for Debug mode" OFF)
+option(USE_DEBUG "Build with debug symbols and without optimization" OFF)
 option(USE_SANITIZER "Use santizer flags" OFF)
+option(USE_OPENMP "Use openMP" ON)
+option(USE_HOMEBREW_FALLBACK "(macOS-only) also look in 'brew --prefix' for libraries (e.g. OpenMP)" ON)
 option(BUILD_TEST "Build C++ tests with Google Test" OFF)
 option(BUILD_DEBUG_TARGETS "Build Standalone C++ Programs for Debugging" ON)
 option(BUILD_PYTHON "Build Shared Library for Python Package" OFF)
@@ -9,8 +11,8 @@ option(BUILD_PYTHON "Build Shared Library for Python Package" OFF)
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
-# Default to CMake 3.16
-cmake_minimum_required(VERSION 3.16)
+# Default to CMake 3.20
+cmake_minimum_required(VERSION 3.20)
 
 # Define the project
 project(stochtree LANGUAGES C CXX)
@@ -34,6 +36,13 @@ if(USE_DEBUG)
     add_definitions(-DDEBUG)
 endif()
 
+# Linker flags (empty by default, updated if using openmp)
+set(
+  STOCHTREE_LINK_FLAGS
+  ""
+)
+
+# Unix / MinGW compiler flags
 if(UNIX OR MINGW OR CYGWIN)
   set(
     CMAKE_CXX_FLAGS
@@ -42,11 +51,12 @@ if(UNIX OR MINGW OR CYGWIN)
   if(USE_DEBUG)
       set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g -O0")
   else()
-      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -O3")
+      set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -g -O3")
   endif()
   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-unknown-pragmas -Wno-unused-private-field")
 endif()
 
+# MSVC compiler flags
 if(MSVC)
     set(
       variables
@@ -72,6 +82,33 @@ else()
     endif()
 endif()
 
+# OpenMP
+if(USE_OPENMP)
+  add_definitions(-DSTOCHTREE_OPENMP_AVAILABLE)
+  if(APPLE)
+    find_package(OpenMP)
+    if(NOT OpenMP_FOUND)
+      if(USE_HOMEBREW_FALLBACK)
+        execute_process(COMMAND brew --prefix libomp
+                        OUTPUT_VARIABLE HOMEBREW_LIBOMP_PREFIX
+                        OUTPUT_STRIP_TRAILING_WHITESPACE)
+        set(OpenMP_C_FLAGS "-Xclang -fopenmp -I${HOMEBREW_LIBOMP_PREFIX}/include")
+        set(OpenMP_CXX_FLAGS "-Xclang -fopenmp -I${HOMEBREW_LIBOMP_PREFIX}/include")
+        set(OpenMP_C_INCLUDE_DIR "")
+        set(OpenMP_CXX_INCLUDE_DIR "")
+        set(OpenMP_C_LIB_NAMES libomp)
+        set(OpenMP_CXX_LIB_NAMES libomp)
+        set(OpenMP_libomp_LIBRARY ${HOMEBREW_LIBOMP_PREFIX}/lib/libomp.dylib)
+      endif()
+      find_package(OpenMP REQUIRED)
+    endif()
+  else()
+    find_package(OpenMP REQUIRED)
+  endif()
+  # Update flags with openmp 
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
+endif()
+
 # Header file directory
 set(StochTree_HEADER_DIR ${PROJECT_SOURCE_DIR}/include)
 
@@ -80,6 +117,8 @@ set(BOOSTMATH_HEADER_DIR ${PROJECT_SOURCE_DIR}/deps/boost_math/include)
 
 # Eigen header file directory
 set(EIGEN_HEADER_DIR ${PROJECT_SOURCE_DIR}/deps/eigen)
+add_definitions(-DEIGEN_MPL2_ONLY)
+add_definitions(-DEIGEN_DONT_PARALLELIZE)
 
 # fast_double_parser header file directory
 set(FAST_DOUBLE_PARSER_HEADER_DIR ${PROJECT_SOURCE_DIR}/deps/fast_double_parser/include)
@@ -109,10 +148,11 @@ file(
 add_library(stochtree_objs OBJECT ${SOURCES})
 
 # Include the headers in the source library
-target_include_directories(stochtree_objs PRIVATE ${StochTree_HEADER_DIR} ${BOOSTMATH_HEADER_DIR} ${EIGEN_HEADER_DIR} ${FAST_DOUBLE_PARSER_HEADER_DIR} ${FMT_HEADER_DIR})
-
-if(APPLE)
-  set(CMAKE_SHARED_LIBRARY_SUFFIX ".so")
+if(USE_OPENMP)
+  target_include_directories(stochtree_objs PRIVATE ${StochTree_HEADER_DIR} ${BOOSTMATH_HEADER_DIR} ${EIGEN_HEADER_DIR} ${FAST_DOUBLE_PARSER_HEADER_DIR} ${FMT_HEADER_DIR} ${OpenMP_CXX_INCLUDE_DIR})
+  target_link_libraries(stochtree_objs PRIVATE ${OpenMP_libomp_LIBRARY})
+else()
+  target_include_directories(stochtree_objs PRIVATE ${StochTree_HEADER_DIR} ${BOOSTMATH_HEADER_DIR} ${EIGEN_HEADER_DIR} ${FAST_DOUBLE_PARSER_HEADER_DIR} ${FMT_HEADER_DIR})
 endif()
 
 # Python shared library
@@ -122,8 +162,13 @@ if (BUILD_PYTHON)
   pybind11_add_module(stochtree_cpp src/py_stochtree.cpp)
 
   # Link to C++ source and headers
-  target_include_directories(stochtree_cpp PRIVATE ${StochTree_HEADER_DIR} ${BOOSTMATH_HEADER_DIR} ${EIGEN_HEADER_DIR} ${FAST_DOUBLE_PARSER_HEADER_DIR} ${FMT_HEADER_DIR})
-  target_link_libraries(stochtree_cpp PRIVATE stochtree_objs)
+  if(USE_OPENMP)
+    target_include_directories(stochtree_cpp PRIVATE ${StochTree_HEADER_DIR} ${BOOSTMATH_HEADER_DIR} ${EIGEN_HEADER_DIR} ${FAST_DOUBLE_PARSER_HEADER_DIR} ${FMT_HEADER_DIR} ${OpenMP_CXX_INCLUDE_DIR})
+    target_link_libraries(stochtree_cpp PRIVATE stochtree_objs ${OpenMP_libomp_LIBRARY})
+  else()
+    target_include_directories(stochtree_cpp PRIVATE ${StochTree_HEADER_DIR} ${BOOSTMATH_HEADER_DIR} ${EIGEN_HEADER_DIR} ${FAST_DOUBLE_PARSER_HEADER_DIR} ${FMT_HEADER_DIR})
+    target_link_libraries(stochtree_cpp PRIVATE stochtree_objs)
+  endif()
 
   # EXAMPLE_VERSION_INFO is defined by setup.py and passed into the C++ code as a
   # define (VERSION_INFO) here.
@@ -154,8 +199,13 @@ if(BUILD_TEST)
   file(GLOB CPP_TEST_SOURCES test/cpp/*.cpp)
   add_executable(teststochtree ${CPP_TEST_SOURCES})
   set(STOCHTREE_TEST_HEADER_DIR ${PROJECT_SOURCE_DIR}/test/cpp)
-  target_include_directories(teststochtree PRIVATE ${StochTree_HEADER_DIR} ${BOOSTMATH_HEADER_DIR} ${EIGEN_HEADER_DIR} ${STOCHTREE_TEST_HEADER_DIR} ${FAST_DOUBLE_PARSER_HEADER_DIR} ${FMT_HEADER_DIR})
-  target_link_libraries(teststochtree PRIVATE stochtree_objs GTest::gtest_main)
+  if(USE_OPENMP)
+    target_include_directories(teststochtree PRIVATE ${StochTree_HEADER_DIR} ${BOOSTMATH_HEADER_DIR} ${EIGEN_HEADER_DIR} ${STOCHTREE_TEST_HEADER_DIR} ${FAST_DOUBLE_PARSER_HEADER_DIR} ${FMT_HEADER_DIR} ${OpenMP_CXX_INCLUDE_DIR})
+    target_link_libraries(teststochtree PRIVATE stochtree_objs GTest::gtest_main ${OpenMP_libomp_LIBRARY})
+  else()
+    target_include_directories(teststochtree PRIVATE ${StochTree_HEADER_DIR} ${BOOSTMATH_HEADER_DIR} ${EIGEN_HEADER_DIR} ${STOCHTREE_TEST_HEADER_DIR} ${FAST_DOUBLE_PARSER_HEADER_DIR} ${FMT_HEADER_DIR})
+    target_link_libraries(teststochtree PRIVATE stochtree_objs GTest::gtest_main)
+  endif()
   gtest_discover_tests(teststochtree)
 endif()
 
@@ -164,7 +214,12 @@ if(BUILD_DEBUG_TARGETS)
   # Build test suite
   add_executable(debugstochtree debug/api_debug.cpp)
   set(StochTree_DEBUG_HEADER_DIR ${PROJECT_SOURCE_DIR}/debug)
-  target_include_directories(debugstochtree PRIVATE ${StochTree_HEADER_DIR} ${BOOSTMATH_HEADER_DIR} ${EIGEN_HEADER_DIR} ${StochTree_DEBUG_HEADER_DIR} ${FAST_DOUBLE_PARSER_HEADER_DIR} ${FMT_HEADER_DIR})
-  target_link_libraries(debugstochtree PRIVATE stochtree_objs)
+  if(USE_OPENMP)
+    target_include_directories(debugstochtree PRIVATE ${StochTree_HEADER_DIR} ${BOOSTMATH_HEADER_DIR} ${EIGEN_HEADER_DIR} ${StochTree_DEBUG_HEADER_DIR} ${FAST_DOUBLE_PARSER_HEADER_DIR} ${FMT_HEADER_DIR} ${OpenMP_CXX_INCLUDE_DIR})
+    target_link_libraries(debugstochtree PRIVATE stochtree_objs ${OpenMP_libomp_LIBRARY})
+  else()
+    target_include_directories(debugstochtree PRIVATE ${StochTree_HEADER_DIR} ${BOOSTMATH_HEADER_DIR} ${EIGEN_HEADER_DIR} ${StochTree_DEBUG_HEADER_DIR} ${FAST_DOUBLE_PARSER_HEADER_DIR} ${FMT_HEADER_DIR})
+    target_link_libraries(debugstochtree PRIVATE stochtree_objs)
+  endif()
 endif()
 

R/bart.R

@@ -51,6 +51,7 @@
 #'   - `rfx_group_parameter_prior_cov` Prior covariance matrix for the random effects "group parameters." Default: `NULL`. Must be a square matrix whose dimension matches the number of random effects bases, or a scalar value that will be expanded to a diagonal matrix.
 #'   - `rfx_variance_prior_shape` Shape parameter for the inverse gamma prior on the variance of the random effects "group parameter." Default: `1`.
 #'   - `rfx_variance_prior_scale` Scale parameter for the inverse gamma prior on the variance of the random effects "group parameter." Default: `1`.
+#'   - `num_threads` Number of threads to use in the GFR and MCMC algorithms, as well as prediction. If OpenMP is not available on a user's setup, this will default to `1`, otherwise to the maximum number of available threads.
 #'
 #' @param mean_forest_params (Optional) A list of mean forest model parameters, each of which has a default value processed internally, so this argument list is optional.
 #'
@@ -130,7 +131,8 @@ bart <- function(X_train, y_train, leaf_basis_train = NULL, rfx_group_ids_train
         rfx_working_parameter_prior_cov = NULL,
         rfx_group_parameter_prior_cov = NULL,
         rfx_variance_prior_shape = 1,
-        rfx_variance_prior_scale = 1
+        rfx_variance_prior_scale = 1,
+        num_threads = -1
     )
     general_params_updated <- preprocessParams(
         general_params_default, general_params
@@ -186,6 +188,7 @@ bart <- function(X_train, y_train, leaf_basis_train = NULL, rfx_group_ids_train
     rfx_group_parameter_prior_cov <- general_params_updated$rfx_group_parameter_prior_cov
     rfx_variance_prior_shape <- general_params_updated$rfx_variance_prior_shape
     rfx_variance_prior_scale <- general_params_updated$rfx_variance_prior_scale
+    num_threads <- general_params_updated$num_threads
 
     # 2. Mean forest parameters
     num_trees_mean <- mean_forest_params_updated$num_trees
@@ -795,7 +798,8 @@ bart <- function(X_train, y_train, leaf_basis_train = NULL, rfx_group_ids_train
                 forest_model_mean$sample_one_iteration(
                     forest_dataset = forest_dataset_train, residual = outcome_train, forest_samples = forest_samples_mean, 
                     active_forest = active_forest_mean, rng = rng, forest_model_config = forest_model_config_mean, 
-                    global_model_config = global_model_config, keep_forest = keep_sample, gfr = TRUE
+                    global_model_config = global_model_config, num_threads = num_threads, 
+                    keep_forest = keep_sample, gfr = TRUE
                 )
 
                 # Cache train set predictions since they are already computed during sampling