ClickHouse/cmake/limit_jobs.cmake

58 lines
2.5 KiB
CMake

# Usage:
# set (MAX_COMPILER_MEMORY 2000 CACHE INTERNAL "") # In megabytes
# set (MAX_LINKER_MEMORY 3500 CACHE INTERNAL "")
# include (cmake/limit_jobs.cmake)
cmake_host_system_information(RESULT AVAILABLE_PHYSICAL_MEMORY QUERY AVAILABLE_PHYSICAL_MEMORY) # Not available under freebsd
cmake_host_system_information(RESULT NUMBER_OF_LOGICAL_CORES QUERY NUMBER_OF_LOGICAL_CORES)
# 1 if not set
option(PARALLEL_COMPILE_JOBS "Maximum number of concurrent compilation jobs" "")
# 1 if not set
option(PARALLEL_LINK_JOBS "Maximum number of concurrent link jobs" "")
if (NOT PARALLEL_COMPILE_JOBS AND AVAILABLE_PHYSICAL_MEMORY AND MAX_COMPILER_MEMORY)
math(EXPR PARALLEL_COMPILE_JOBS ${AVAILABLE_PHYSICAL_MEMORY}/${MAX_COMPILER_MEMORY})
if (NOT PARALLEL_COMPILE_JOBS)
set (PARALLEL_COMPILE_JOBS 1)
endif ()
endif ()
if (PARALLEL_COMPILE_JOBS AND (NOT NUMBER_OF_LOGICAL_CORES OR PARALLEL_COMPILE_JOBS LESS NUMBER_OF_LOGICAL_CORES))
set(CMAKE_JOB_POOL_COMPILE compile_job_pool${CMAKE_CURRENT_SOURCE_DIR})
string (REGEX REPLACE "[^a-zA-Z0-9]+" "_" CMAKE_JOB_POOL_COMPILE ${CMAKE_JOB_POOL_COMPILE})
set_property(GLOBAL APPEND PROPERTY JOB_POOLS ${CMAKE_JOB_POOL_COMPILE}=${PARALLEL_COMPILE_JOBS})
endif ()
if (NOT PARALLEL_LINK_JOBS AND AVAILABLE_PHYSICAL_MEMORY AND MAX_LINKER_MEMORY)
math(EXPR PARALLEL_LINK_JOBS ${AVAILABLE_PHYSICAL_MEMORY}/${MAX_LINKER_MEMORY})
if (NOT PARALLEL_LINK_JOBS)
set (PARALLEL_LINK_JOBS 1)
endif ()
endif ()
# ThinLTO provides its own parallel linking
# But use 2 parallel jobs, since:
# - this is what llvm does
# - and I've verfied that lld-11 does not use all available CPU time (in peak) while linking one binary
if (ENABLE_THINLTO AND PARALLEL_LINK_JOBS GREATER 2)
message(STATUS "ThinLTO provides its own parallel linking - limiting parallel link jobs to 2.")
set (PARALLEL_LINK_JOBS 2)
endif()
if (PARALLEL_LINK_JOBS AND (NOT NUMBER_OF_LOGICAL_CORES OR PARALLEL_COMPILE_JOBS LESS NUMBER_OF_LOGICAL_CORES))
set(CMAKE_JOB_POOL_LINK link_job_pool${CMAKE_CURRENT_SOURCE_DIR})
string (REGEX REPLACE "[^a-zA-Z0-9]+" "_" CMAKE_JOB_POOL_LINK ${CMAKE_JOB_POOL_LINK})
set_property(GLOBAL APPEND PROPERTY JOB_POOLS ${CMAKE_JOB_POOL_LINK}=${PARALLEL_LINK_JOBS})
endif ()
if (PARALLEL_COMPILE_JOBS OR PARALLEL_LINK_JOBS)
message(STATUS
"${CMAKE_CURRENT_SOURCE_DIR}: Have ${AVAILABLE_PHYSICAL_MEMORY} megabytes of memory.
Limiting concurrent linkers jobs to ${PARALLEL_LINK_JOBS} and compiler jobs to ${PARALLEL_COMPILE_JOBS}")
endif ()