brew install gperftools graphviz
Then configure and make Ruby with the profiling library linked
begin
set -lx LIBS '-lprofiler'
set -lx cflags '-fno-omit-frame-pointer'
set -lx LDFLAGS '-Wl,-no_pie'
set -lx debugflags '-g'
set -lx optflags '-O0'
set -lx RUBY_DEVEL 'yes'
../ruby/configure --prefix=/Users/mattvh/src/ruby/install --disable-install-doc --with-openssl-dir=(brew --prefix)/opt/openssl
end
Once this has been done you can set the environment variable CPUPROFILE to a
file path in order to have the binary write profiling informatin to the file at
that path.
So to run our test.rb with miniruby and generate a profile we can do this
CPUPROFILE=./master.prof ./miniruby -I../ruby/lib -I. -I.ext/common ../ruby/test.rb
Then you can use the pprof tool to inspect the results by passing in the
profile file and the compiled binary that generated the profile.
pprof ./miniruby ./master.prof
This will dump you into a repl where you can get various different kinds of
visualisations and outputs. You can pass args to the cli if you know what you
need.
--text Generate text report
--stacks Generate stack traces similar to the heap profiler (requires --text)
--callgrind Generate callgrind format to stdout
--gv Generate Postscript and display
--evince Generate PDF and display
--web Generate SVG and display
--list=<regexp> Generate source listing of matching routines
--disasm=<regexp> Generate disassembly of matching routines
--symbols Print demangled symbol names found at given addresses
--dot Generate DOT file to stdout
--ps Generate Postscript to stdout
--pdf Generate PDF to stdout
--svg Generate SVG to stdout
--gif Generate GIF to stdout
--raw Generate symbolized pprof data (useful with remote fetch)
--collapsed Generate collapsed stacks for building flame graphs
(see http://www.brendangregg.com/flamegraphs.html)