eileencodes 34a2acdac7 Add a cache for class variables ... This change implements a cache for class variables. Previously there was no cache for cvars. Cvar access is slow due to needing to travel all the way up th ancestor tree before returning the cvar value. The deeper the ancestor tree the slower cvar access will be. The benefits of the cache are more visible with a higher number of included modules due to the way Ruby looks up class variables. The benchmark here includes 26 modules and shows with the cache, this branch is 6.5x faster when accessing class variables. ``` compare-ruby: ruby 3.1.0dev (2021-03-15T06:22:34Z master 9e5105ca45) [x86_64-darwin19] built-ruby: ruby 3.1.0dev (2021-03-15T12:12:44Z add-cache-for-clas.. c6be0093ae) [x86_64-darwin19] | |compare-ruby|built-ruby| |:--------|-----------:|---------:| |vm_cvar | 5.681M| 36.980M| | | -| 6.51x| ``` Benchmark.ips calling `ActiveRecord::Base.logger` from within a Rails application. ActiveRecord::Base.logger has 71 ancestors. The more ancestors a tree has, the more clear the speed increase. IE if Base had only one ancestor we'd see no improvement. This benchmark is run on a vanilla Rails application. Benchmark code: ```ruby require "benchmark/ips" require_relative "config/environment" Benchmark.ips do |x| x.report "logger" do ActiveRecord::Base.logger end end ``` Ruby 3.0 master / Rails 6.1: ``` Warming up -------------------------------------- logger 155.251k i/100ms Calculating ------------------------------------- ``` Ruby 3.0 with cvar cache / Rails 6.1: ``` Warming up -------------------------------------- logger 1.546M i/100ms Calculating ------------------------------------- logger 14.857M (± 4.8%) i/s - 74.198M in 5.006202s ``` Lastly we ran a benchmark to demonstate the difference between master and our cache when the number of modules increases. This benchmark measures 1 ancestor, 30 ancestors, and 100 ancestors. Ruby 3.0 master: ``` Warming up -------------------------------------- 1 module 1.231M i/100ms 30 modules 432.020k i/100ms 100 modules 145.399k i/100ms Calculating ------------------------------------- 1 module 12.210M (± 2.1%) i/s - 61.553M in 5.043400s 30 modules 4.354M (± 2.7%) i/s - 22.033M in 5.063839s 100 modules 1.434M (± 2.9%) i/s - 7.270M in 5.072531s Comparison: 1 module: 12209958.3 i/s 30 modules: 4354217.8 i/s - 2.80x (± 0.00) slower 100 modules: 1434447.3 i/s - 8.51x (± 0.00) slower ``` Ruby 3.0 with cvar cache: ``` Warming up -------------------------------------- 1 module 1.641M i/100ms 30 modules 1.655M i/100ms 100 modules 1.620M i/100ms Calculating ------------------------------------- 1 module 16.279M (± 3.8%) i/s - 82.038M in 5.046923s 30 modules 15.891M (± 3.9%) i/s - 79.459M in 5.007958s 100 modules 16.087M (± 3.6%) i/s - 81.005M in 5.041931s Comparison: 1 module: 16279458.0 i/s 100 modules: 16087484.6 i/s - same-ish: difference falls within error 30 modules: 15891406.2 i/s - same-ish: difference falls within error ``` Co-authored-by: Aaron Patterson <tenderlove@ruby-lang.org>		2021-05-11 13:27:06 -04:00
..
arithmetic	Inline LONG_LONG conversions	2021-04-13 14:50:13 +09:00
attr	Fix trivial -Wundef warnings	2021-05-04 14:56:55 +02:00
compiler_is
core	Add RBIMPL_RVALUE_EMBED_LEN_MAX neeeded by internal/bignum.h	2021-05-04 14:56:55 +02:00
has	Fix -Wundef warnings for RBIMPL_HAS_BUILTIN	2021-05-04 14:56:55 +02:00
intern	Add a cache for class variables	2021-05-11 13:27:06 -04:00
anyargs.h
arithmetic.h
assume.h	Revert "RBIMPL_UNREACHABLE_RETURN: evaluate the argument"	2020-06-29 12:33:17 +09:00
cast.h
compiler_is.h
compiler_since.h	Fix some typos by spell checker	2021-04-26 10:07:41 +09:00
config.h	Omit checks for C89 standard or later	2020-12-12 17:02:42 +09:00
constant_p.h
core.h	Fix some typos by spell checker	2021-04-26 10:07:41 +09:00
ctype.h
dllexport.h
dosish.h
error.h	Use category: :experimental in warnings that are related to experimental features	2020-12-18 09:54:11 -08:00
eval.h
event.h
fl_type.h	Fix compilation errors for c99	2021-05-04 20:38:03 -04:00
gc.h	Fix docs about movement for rb_gc_register_mark_object()	2020-12-01 15:23:09 -05:00
glob.h
globals.h	rb_cCont: no longer exists	2020-12-22 15:25:03 +09:00
interpreter.h	ruby_set_stack_size: no longer exists	2020-12-18 11:18:09 +09:00
iterator.h
memory.h	Fixed dangling imemo_tmpbuf	2021-01-02 12:11:52 +09:00
method.h
module.h	Add compaction notes for class/module creation C APIs	2021-01-26 16:24:01 -08:00
newobj.h	kill CLONESETUP and DUPSETUP	2021-01-27 09:30:15 +09:00
rgengc.h	Use RUBY_DEBUG instead of NDEBUG	2020-05-26 03:21:14 +09:00
scan_args.h	Added UNREACHABLE_RETURN	2020-05-21 13:31:36 +09:00
special_consts.h
static_assert.h
stdalign.h	Fixed a typo [Bug #17522]	2021-01-09 13:37:41 +09:00
stdbool.h
symbol.h
value.h
value_type.h	Allow newobj_of0 and newobj_slowpath to allocate into multiple heap slots	2021-05-06 09:18:17 -04:00
variable.h
warning_push.h	Fix some typos by spell checker	2021-04-26 10:07:41 +09:00
xmalloc.h	include/ruby/internal/xmalloc.h: document rb_eNoMemError	2020-12-21 11:01:01 +09:00