Profiling MAPL Builds

Building MAPL with Ninja

Profiling MAPL builds is fairly simple but requires a non-standard build, namely a Ninja build. First, clone MAPL per usual:

mepo clone [email protected]:GEOS-ESM/MAPL.git

and checkout your favorite branch. Then run CMake:

cmake -B build -S . --install-prefix=$(pwd)/install -DCMAKE_BUILD_TYPE=Debug -G Ninja

Then you can build and install with:

cmake --build build --target install -j 8

Checking the build times on CLI

To look at the build times on the CLI, you can use this script:

#!/usr/bin/env gawk -f

!/^#/ {
    TIMES[$4] += ($2 - $1)/1000
    COUNT[$4] += 1
}

END {
    for (TGT in TIMES)
        AVG[TGT]=TIMES[TGT]/COUNT[TGT]
    asorti(AVG, SORTED, "@val_num_desc")
    for (num in SORTED)
        print AVG[SORTED[num]] " " SORTED[num]
}

If saved as show-ninja-build-stats, you can run:

$ show-ninja-build-stats build/.ninja_log | grep -v 'mod$' | head
34.786 gridcomps/ExtData2G/CMakeFiles/MAPL.ExtData2G.dir/ExtDataGridCompNG.F90.o
33.706 base/CMakeFiles/MAPL.base.dir/Base.F90.o
28.799 gridcomps/History/CMakeFiles/MAPL.history.dir/MAPL_HistoryGridComp.F90.o
25.658 Apps/CMakeFiles/Regrid_Util.x.dir/Regrid_Util.F90.o
25.497 gridcomps/ExtData/CMakeFiles/MAPL.ExtData.dir/ExtDataGridCompMod.F90.o
20.136 gridcomps/History/CMakeFiles/MAPL.history.dir/MAPL_HistoryCollection.F90.o
15.395 gridcomps/History/CMakeFiles/MAPL.history.dir/Sampler/MAPL_EpochSwathMod.F90.o
14.97 base/CMakeFiles/MAPL.base.dir/MAPL_CFIO.F90.o
14.644 generic/CMakeFiles/MAPL.generic.dir/MAPL_Generic.F90.o
13.423 gridcomps/History/CMakeFiles/MAPL.history.dir/Sampler/MAPL_TrajectoryMod_smod.F90.o

These are the top 10 files in time of compilation.

Obtaining Trace

To get the profile trace, we will use the ninjatracing code by @nico:

https://github.com/nico/ninjatracing

This code can convert .ninja_log files into a format that can be read by Chromium's trace format.

If you don't already have it, clone the repo and then run:

ninjatracing build/.ninja_log > trace.json

or wherever your build from above is.

Displaying trace

To display the trace, copy your JSON file to your local machine, go to https://ui.perfetto.dev/ and click "Open Trace File". Navigate to your trace file and open it. You'll see something like:

The longer the bar, the longer the time to compile. In the example above, it matches the CLI output for the tall poles.