yjit-trace-exits appends a synthetic sample for the instruction being
exited, but we didn't increment the size of the stack. Fixing this count
correctly lets us successfully generate a flamegraph from the exits.
I also replaced the line number for instructions with 0, as I don't
think the previous value had meaning.
Co-authored-by: Adam Hess <HParker@github.com>
The stackprof-format raw samples are suffixed with a count (ie. how many
times did the previously recorded side-exit repeat). Previously we were
correctly using this value to increment the :samples count, but not the
:total_samples count or edges.
This made the stackprof aggregate results incorrect (though any
flamegraphs generated should have been correct, since those only rely on
raw samples).
* YJIT: Add --yjit-pause and RubyVM::YJIT.resume
This allows booting YJIT in a suspended state. We chose to add a new
command line option as opposed to simply allowing YJIT.resume to work
without any command line option because it allows for combining with
YJIT tuning command line options. It also simpifies implementation.
Paired with Kokubun and Maxime.
* Update yjit.rb
Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
---------
Co-authored-by: Alan Wu <XrXr@users.noreply.github.com>
Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
Early total_exits condition.
Replace Array#sort_by/first(how_many) with Array#max_by(how_many).
Replace Array#map/max with Array#max_by, match print_counters style for longest_name_length.
Tested on production workloads at Shopify for > 1 year and proven
to be quite stable. Enabling YJIT at run-time is still guarded
behind the --yjit command-line option for now.
* Enable --yjit-stats for release builds
In order for people in the real world to report information about how their application runs with YJIT, we want to expose stats without requiring rebuilding ruby. We can do this without overhead, with the exception of count ratio in yjit, since this relies on the interpreter also counting instructions.
This change exposes those stats, while not showing ratio in yjit if we are not in a stats build.
* Update yjit.rb
Co-authored-by: Takashi Kokubun <takashikkbn@gmail.com>
Co-authored-by: Maxime Chevalier-Boisvert <maximechevalierb@gmail.com>
While I was working on my RubyConf talk for tracing yjit exit locations
I realized that there were exits from the dump code included in the
stats data. For example I saw 224 interp leave exits for a simple script
that should have had 1 or 2. I realized that the dump code needs to be
called _after_ the stats are generated, otherwise the dump code will be
counted in the stats exits.
I've added a `_dump_locations` method to the `at_exit` for stats
generation to ensure that it runs last. I've updated the documentation
to add a note that if you call `dump_exit_locations` directly, your
stats will include the dump code exits as well.
Maxime Chevalier-Boisvert
ywenc
Takashi Kokubun
Noah Gibbs
John Hawthorn
Mau Magnaguagno
Jimmy Miller
Eileen M. Uchitelle