module ZJIT

This module allows for introspection of ZJIT, CRuby’s just-in-time compiler. Everything in the module is highly implementation specific and the API might be less stable compared to the standard library.

This module may not exist if ZJIT does not support the particular platform for which CRuby is built.

Public Class Methods

enabled? ()

Source

# File zjit.rb, line 18
def enabled?
  Primitive.cexpr! 'RBOOL(rb_zjit_enabled_p)'
end

Check if ZJIT is enabled

reset_stats! ()

Source

# File zjit.rb, line 33
def reset_stats!
  Primitive.rb_zjit_reset_stats_bang
end

Discard statistics collected for ‘–zjit-stats`.

stats (target_key = nil)

Source

# File zjit.rb, line 28
def stats(target_key = nil)
  Primitive.rb_zjit_stats(target_key)
end

Return ZJIT statistics as a Hash

stats_enabled? ()

Source

# File zjit.rb, line 23
def stats_enabled?
  Primitive.rb_zjit_stats_enabled_p
end

Check if ‘–zjit-stats` is used

stats_string ()

Source

# File zjit.rb, line 38
def stats_string
  buf = +"***ZJIT: Printing ZJIT statistics on exit***\n"
  stats = self.stats

  # Show exit reasons, ordered by the typical amount of exits for the prefix at the time
  print_counters_with_prefix(prefix: 'unhandled_call_', prompt: 'unhandled call types', buf:, stats:, limit: 20)
  print_counters_with_prefix(prefix: 'unhandled_yarv_insn_', prompt: 'unhandled YARV insns', buf:, stats:, limit: 20)
  print_counters_with_prefix(prefix: 'compile_error_', prompt: 'compile error reasons', buf:, stats:, limit: 20)
  print_counters_with_prefix(prefix: 'exit_', prompt: 'side exit reasons', buf:, stats:, limit: 20)
  print_counters_with_prefix(prefix: 'dynamic_send_type_', prompt: 'dynamic send types', buf:, stats:, limit: 20)

  # Show the most important stats ratio_in_zjit at the end
  print_counters([
    :dynamic_send_count,

    :compiled_iseq_count,
    :failed_iseq_count,

    :compile_time_ns,
    :profile_time_ns,
    :gc_time_ns,
    :invalidation_time_ns,

    :code_region_bytes,
    :side_exit_count,
    :total_insn_count,
    :vm_insn_count,
    :zjit_insn_count,
    :ratio_in_zjit,
  ], buf:, stats:)

  buf
end

Get the summary of ZJIT statistics as a String