如何在 CMake 中测量每个对象的编译时间？

Question

I'm searching for tool that helps calculate compilation time using CMake. Target project builds a lot of files, so I need to craft some "table" per each module. For example, project consists of 2 files - main.cc and libs.cc I need to calculate build time for libs and main differently.

I'm trying to set wrapper for g++, but in make -j4 it has some "race condition". Strings with Building status and building time are crossing.

.......
[  3%] Building CXX object irohad/simulator/CMakeFiles/block_creator_common.dir/block_creator_common.o
0.12    1.42
[  4%] Building CXX object schema/CMakeFiles/yac_grpc.dir/yac.grpc.pb.o
0.13    1.36
0.10    0.71
.......

Set new "Compiler" - wrapper for g++

#!/bin/bash
{ /usr/bin/time -f "%S\t%U" g++ "$@"; } 2> >(cat <(echo "g++ $@") - | cat)

and then

cmake -H. -Bbuild -DCMAKE_CXX_COMPILER=/path/to/script.sh
make | tee -a buildResults.txt

Answer 1

Please try adding following lines in the cmake, to measure time you can compile with single cpu and then run in parallel mode

set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE "${CMAKE_COMMAND} -E time")

set_property(TARGET <your target> PROPERTY RULE_LAUNCH_COMPILE "${CMAKE_COMMAND} -E time")

replace per your project name.

Hope this helps.

Answer 2

My solution is:

#!/bin/bash
( /usr/bin/time -f "%S\t%U" g++ "$@" 2> >(cat <(echo "g++ $@") - )) | sponge

sponge allows to put output only after program exits

Answer 3

你可以试试这个

set_property(GLOBAL PROPERTY RULE_LAUNCH_COMPILE "${CMAKE_COMMAND} -E time") set_property(GLOBAL PROPERTY RULE_LAUNCH_LINK "${CMAKE_COMMAND} -E time")