Add support for --split-compile and --jobserver in build.sh

Makefile

@@ -0,0 +1,15 @@
+# SPDX-FileCopyrightText: Copyright (c) 2025, NVIDIA CORPORATION. All rights reserved.
+# SPDX-License-Identifier: Apache-2.0
+
+# Makefile
+
+LIBCUOPT_BUILD_DIR ?= cpp/build
+VERBOSE_FLAG ?=
+PARALLEL_LEVEL ?=
+
+.PHONY: all ninja-build
+
+all: ninja-build
+
+ninja-build:
+	cmake --build $(LIBCUOPT_BUILD_DIR) $(VERBOSE_FLAG) $(if $(PARALLEL_LEVEL),-j$(PARALLEL_LEVEL),)

build.sh

@@ -15,7 +15,7 @@ REPODIR=$(cd "$(dirname "$0")"; pwd)
 LIBCUOPT_BUILD_DIR=${LIBCUOPT_BUILD_DIR:=${REPODIR}/cpp/build}
 LIBMPS_PARSER_BUILD_DIR=${LIBMPS_PARSER_BUILD_DIR:=${REPODIR}/cpp/libmps_parser/build}
 
-VALIDARGS="clean libcuopt libmps_parser cuopt_mps_parser cuopt cuopt_server cuopt_sh_client docs deb -a -b -g -fsanitize -v -l= --verbose-pdlp --build-lp-only  --no-fetch-rapids --skip-c-python-adapters --skip-tests-build --skip-routing-build --skip-fatbin-write --host-lineinfo [--cmake-args=\\\"<args>\\\"] [--cache-tool=<tool>] -n --allgpuarch --ci-only-arch --show_depr_warn -h --help"
+VALIDARGS="clean libcuopt libmps_parser cuopt_mps_parser cuopt cuopt_server cuopt_sh_client docs deb -a -b -g -fsanitize -v -j -l= --verbose-pdlp --build-lp-only  --no-fetch-rapids --skip-c-python-adapters --skip-tests-build --skip-routing-build --skip-fatbin-write --host-lineinfo [--cmake-args=\\\"<args>\\\"] [--cache-tool=<tool>] -n --allgpuarch --ci-only-arch --show_depr_warn -h --help"
 HELP="$0 [<target> ...] [<flag> ...]
  where <target> is:
    clean            - remove all existing build artifacts and configuration (start over)
@@ -34,6 +34,7 @@ HELP="$0 [<target> ...] [<flag> ...]
    -b               - Build with benchmark settings
    -fsanitize       - Build with sanitizer
    -n               - no install step
+   -j               - parallel build jobs (unlimited if no value, or -j<N> for N threads)
    --no-fetch-rapids  - don't fetch rapids dependencies
    -l=              - log level. Options are: TRACE | DEBUG | INFO | WARN | ERROR | CRITICAL | OFF. Default=INFO
    --verbose-pdlp   - verbose mode for pdlp solver
@@ -85,6 +86,7 @@ CACHE_ARGS=()
 PYTHON_ARGS_FOR_INSTALL=("-m" "pip" "install" "--no-build-isolation" "--no-deps")
 LOGGING_ACTIVE_LEVEL="INFO"
 FETCH_RAPIDS=ON
+PARALLEL_LEVEL=""
 
 # Set defaults for vars that may not have been defined externally
 #  FIXME: if PREFIX is not set, check CONDA_PREFIX, but there is no fallback
@@ -172,6 +174,26 @@ function cmakeArgs {
     read -ra EXTRA_CMAKE_ARGS <<< "$EXTRA_CMAKE_ARGS"
 }
 
+function parallelArgs {
+    # Check for -j option
+    if [[ -n $(echo "$ARGS" | { grep -E "\-j" || true; } ) ]]; then
+        # Extract -j with optional number (e.g., -j, -j8, -j16)
+        PARALLEL_ARG=$(echo "$ARGS" | { grep -Eo "\-j[0-9]*" || true; } | head -1)
+        if [[ -n ${PARALLEL_ARG} ]]; then
+            # Remove the -j argument from list of args so that it passes validArgs function
+            ARGS=${ARGS//$PARALLEL_ARG/}
+            # Extract the number if present
+            PARALLEL_NUM=$(echo "$PARALLEL_ARG" | sed 's/-j//')
+            if [[ -z ${PARALLEL_NUM} ]]; then
+                # If no number specified, use nproc
+                PARALLEL_LEVEL=$(nproc)
+            else
+                PARALLEL_LEVEL=${PARALLEL_NUM}
+            fi
+        fi
+    fi
+}
+
 
 if hasArg -h || hasArg --help; then
     echo "${HELP}"
@@ -183,6 +205,7 @@ if (( NUMARGS != 0 )); then
     cacheTool
     cmakeArgs
     loggingArgs
+    parallelArgs
     for a in ${ARGS}; do
         if ! (echo " ${VALIDARGS} " | grep -q " ${a} "); then
             echo "Invalid option: ${a}"
@@ -349,13 +372,19 @@ if buildAll || hasArg libcuopt; then
           -DSKIP_ROUTING_BUILD=${SKIP_ROUTING_BUILD} \
           -DWRITE_FATBIN=${WRITE_FATBIN} \
           -DHOST_LINEINFO=${HOST_LINEINFO} \
+          -DPARALLEL_LEVEL="${PARALLEL_LEVEL}" \
           "${CACHE_ARGS[@]}" \
           "${EXTRA_CMAKE_ARGS[@]}" \
           "${REPODIR}"/cpp
     if hasArg -n; then
-        cmake --build "${LIBCUOPT_BUILD_DIR}" ${VERBOSE_FLAG}
+        # Manual make invocation to start its jobserver
+        make -j${PARALLEL_LEVEL} -C "${REPODIR}" LIBCUOPT_BUILD_DIR="${LIBCUOPT_BUILD_DIR}" VERBOSE_FLAG="${VERBOSE_FLAG}" PARALLEL_LEVEL="${PARALLEL_LEVEL}" ninja-build
     else
-        cmake --build "${LIBCUOPT_BUILD_DIR}" --target ${INSTALL_TARGET} ${VERBOSE_FLAG} -j"${PARALLEL_LEVEL}"
+        if [[ -n "${PARALLEL_LEVEL}" ]]; then
+            cmake --build "${LIBCUOPT_BUILD_DIR}" --target ${INSTALL_TARGET} ${VERBOSE_FLAG} -j"${PARALLEL_LEVEL}"
+        else
+            cmake --build "${LIBCUOPT_BUILD_DIR}" --target ${INSTALL_TARGET} ${VERBOSE_FLAG}
+        fi
     fi
 fi
 

conda/recipes/libcuopt/recipe.yaml

@@ -55,6 +55,7 @@ cache:
       - ${{ stdlib("c") }}
       - cuda-version =${{ cuda_version }}
       - cmake ${{ cmake_version }}
+      - make
       - ninja
       - tbb-devel
       - zlib

cpp/CMakeLists.txt

@@ -124,6 +124,11 @@ if(CMAKE_CUDA_COMPILER_VERSION VERSION_GREATER_EQUAL 12.9 AND CMAKE_CUDA_COMPILE
 endif()
 list(APPEND CUOPT_CUDA_FLAGS -fopenmp)
 
+# Add jobserver flags for parallel compilation if PARALLEL_LEVEL is set
+if(PARALLEL_LEVEL AND NOT "${PARALLEL_LEVEL}" STREQUAL "")
+  message(STATUS "Enabling nvcc jobserver support for parallel builds")
+  list(APPEND CUOPT_CUDA_FLAGS --threads=0 --split-compile=0 --jobserver)
+endif()
 
 if(NOT DISABLE_OPENMP)
   find_package(OpenMP)