mirror of
https://github.com/ruby/ruby.git
synced 2026-01-27 12:34:21 +00:00
The following code previously caused a crash:
```ruby
h = {}
1000000.times{|i| h[i.to_s.to_sym] = i}
def f(kw: 1, **kws) end
f(**h)
```
Inside a thread or fiber, the size of the keyword splat could be much smaller
and still cause a crash.
I found this issue while optimizing method calling by reducing implicit
allocations. Given the following code:
```ruby
def f(kw: , **kws) end
kw = {kw: 1}
f(**kw)
```
The `f(**kw)` call previously allocated two hashes callee side instead of a
single hash. This is because `setup_parameters_complex` would extract the
keywords from the keyword splat hash to the C stack, to attempt to mirror
the case when literal keywords are passed without a keyword splat. Then,
`make_rest_kw_hash` would build a new hash based on the extracted keywords
that weren't used for literal keywords.
Switch the implementation so that if a keyword splat is passed, literal keywords
are deleted from the keyword splat hash (or a copy of the hash if the hash is
not mutable).
In addition to avoiding the crash, this new approach is much more
efficient in all cases. With the included benchmark:
```
1
miniruby: 5247879.9 i/s
miniruby-before: 2474050.2 i/s - 2.12x slower
1_mutable
miniruby: 1797036.5 i/s
miniruby-before: 1239543.3 i/s - 1.45x slower
10
miniruby: 1094750.1 i/s
miniruby-before: 365529.6 i/s - 2.99x slower
10_mutable
miniruby: 407781.7 i/s
miniruby-before: 225364.0 i/s - 1.81x slower
100
miniruby: 100992.3 i/s
miniruby-before: 32703.6 i/s - 3.09x slower
100_mutable
miniruby: 40092.3 i/s
miniruby-before: 21266.9 i/s - 1.89x slower
1000
miniruby: 21694.2 i/s
miniruby-before: 4949.8 i/s - 4.38x slower
1000_mutable
miniruby: 5819.5 i/s
miniruby-before: 2995.0 i/s - 1.94x slower
```
ruby/benchmark
This directory has benchmark definitions to be run with benchmark_driver.gem.
Normal usage
Execute gem install benchmark_driver and run a command like:
# Run a benchmark script with the ruby in the $PATH
benchmark-driver benchmark/app_fib.rb
# Run benchmark scripts with multiple Ruby executables or options
benchmark-driver benchmark/*.rb -e /path/to/ruby -e '/path/to/ruby --jit'
# Or compare Ruby versions managed by rbenv
benchmark-driver benchmark/*.rb --rbenv '2.5.1;2.6.0-preview2 --jit'
# You can collect many metrics in many ways
benchmark-driver benchmark/*.rb --runner memory --output markdown
# Some are defined with YAML for complex setup or accurate measurement
benchmark-driver benchmark/*.yml
See also:
Usage: benchmark-driver [options] RUBY|YAML...
-r, --runner TYPE Specify runner type: ips, time, memory, once, block (default: ips)
-o, --output TYPE Specify output type: compare, simple, markdown, record, all (default: compare)
-e, --executables EXECS Ruby executables (e1::path1 arg1; e2::path2 arg2;...)
--rbenv VERSIONS Ruby executables in rbenv (x.x.x arg1;y.y.y arg2;...)
--repeat-count NUM Try benchmark NUM times and use the fastest result or the worst memory usage
--repeat-result TYPE Yield "best", "average" or "worst" result with --repeat-count (default: best)
--alternate Alternate executables instead of running the same executable in a row with --repeat-count
--bundler Install and use gems specified in Gemfile
--filter REGEXP Filter out benchmarks with given regexp
--run-duration SECONDS Warmup estimates loop_count to run for this duration (default: 3)
--timeout SECONDS Timeout ruby command execution with timeout(1)
-v, --verbose Verbose mode. Multiple -v options increase visilibity (max: 2)
make benchmark
Using make benchmark, make update-benchmark-driver automatically downloads
the supported version of benchmark_driver, and it runs benchmarks with the downloaded
benchmark_driver.
# Run all benchmarks with the ruby in the $PATH and the built ruby
make benchmark
# Or compare with specific ruby binary
make benchmark COMPARE_RUBY="/path/to/ruby --jit"
# Run vm benchmarks
make benchmark ITEM=vm
# Run some limited benchmarks in ITEM-matched files
make benchmark ITEM=vm OPTS=--filter=block
# You can specify the benchmark by an exact filename instead of using the default argument:
# ARGS = $$(find $(srcdir)/benchmark -maxdepth 1 -name '*$(ITEM)*.yml' -o -name '*$(ITEM)*.rb')
make benchmark ARGS=benchmark/erb_render.yml
# You can specify any option via $OPTS
make benchmark OPTS="--help"
# With `make benchmark`, some special runner plugins are available:
# -r peak, -r size, -r total, -r utime, -r stime, -r cutime, -r cstime
make benchmark ITEM=vm_bigarray OPTS="-r peak"