high memory usage

[dorianmariecom]

retained memory by gem
-----------------------------------
   2643413  dead_end-3.1.1

allocated objects by location
-----------------------------------
    252404  /Users/dorianmariefr/.rvm/gems/ruby-3.0.3/gems/dead_end-3.1.1/lib/dead_end/core_ext.rb:19
    118590  /Users/dorianmariefr/.rvm/gems/ruby-3.0.3/gems/dead_end-3.1.1/lib/dead_end/core_ext.rb:30

allocated objects by file
-----------------------------------
    372794  /Users/dorianmariefr/.rvm/gems/ruby-3.0.3/gems/dead_end-3.1.1/lib/dead_end/core_ext.rb

allocated objects by gem
-----------------------------------
    372794  dead_end-3.1.1

and in case it might be useful:

allocated memory by class
-----------------------------------
  30325876  String
  15374176  File
   3715336  Class
   3533088  Hash
   2718504  Array
   2186776  MatchData
    825600  Proc
    630626  Regexp
    596920  Module

this gem is in my bundle because I run the derailed benchmarks

[dorianmariecom]

basically 40MB it seems like

[dorianmariecom]

oops forgot to put derailed_benchmarks in development group

[dorianmariecom]

hmmm even in development it is required by bundle exec derailed bundle:objects

[schneems]

Memory profiler

That line in dead end isn't doing anything, it's forwarding to your original require call https://github.com/zombocom/dead_end/blob/10232e47fbf4c1372f92b3057cbdc9876f771ca9/lib/dead_end/core_ext.rb#L19. You'll have the same issue if you put bootstrap (or any other gem that aliasesrequire).

Basically whatever file you're loading is actually allocating all that memory. Dead end is getting the blame because it's in the middle.

Dead end monkeypatching

The reason dead end needs that monkeypatch is SyntaxError cannot be monkeypatched. There's a plan to move SyntaxError to be patchable via Ruby core, then we could hook into the exception directly instead of this round-about method which causes confusing results like this sometimes.

Getting require memory with dead_end

If the memory is showing up at boot/require time then it should show up with the other tasks: bundle exec derailed bundle:mem or bundle exec derailed bundle:objects.

Fun fact, derailed uses the same trick to profile require memory (overwriting require) as dead end uses to catch syntax errors today.

[dorianmariecom]

ok makes sense thanks