when RubyVM.show_debug_counters is explicitly called.
According to the original description in 70fd099220,
I think it's not intended to use the exit counter at all, and I'd like
to skip it when I need to explicitly call this.
for debug counters
```
../include/ruby/intern.h:1175:137: warning: passing argument 3 of 'rb_define_singleton_method0' from incompatible pointer type [-Wincompatible-pointer-types]
#define rb_define_singleton_method(klass, mid, func, arity) rb_define_singleton_method_choose_prototypem3((arity),(func))((klass),(mid),(func),(arity));
^
../vm.c:2958:5: note: in expansion of macro 'rb_define_singleton_method'
rb_define_singleton_method(rb_cRubyVM, "show_debug_counters", rb_debug_counter_show, 0);
^~~~~~~~~~~~~~~~~~~~~~~~~~
../include/ruby/intern.h:1139:99: note: expected 'VALUE (*)(VALUE) {aka long unsigned int (*)(long unsigned int)}' but argument is of type 'VALUE (*)(void) {aka long unsigned int (*)(void)}'
__attribute__((__unused__,__weakref__("rb_define_singleton_method"),__nonnull__(2,3)))static void rb_define_singleton_method0 (VALUE,const char*,VALUE(*)(VALUE),int);
```
I am trying to study debug counters inside a Rails application.
Accessing debug counters by killing the process is hard because child
processes don't get the same TRAP as the parent, and Rails seems to
intercept calls to `exit`. Adding this method lets me print the debug
counters when I want (at the end of requests for example)
is defined. It's 0 by default and so it dissappears on actual build.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67544 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* debug_counter.h: add the following counters.
* frame_push: control frame counts (total counts).
* frame_push_*: control frame counts per every frame type.
* obj_*: add free'ed counts for each type.
* gc.c: ditto.
* vm_insnhelper.c (vm_push_frame): ditto.
* debug_counter.c (rb_debug_counter_show_results): widen counts field
to show >10G numbers.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64867 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* How to enable this feature?
* define USE_DEBUG_COUNTER as 1.
* you can disable to output the result with
RUBY_DEBUG_COUNTER_DISABLE environment variable
even if USE_DEBUG_COUNTER == 1.
* How to add new counter?
* add COUNTER(<name>) line on debug_counter.h.
* include "debug_counter.h"
* insert RB_DEBUG_COUNTER_INC(<name>) line on your favorite place.
* counter output example:
[RUBY_DEBUG_COUNTER] mc_inline_hit 999
[RUBY_DEBUG_COUNTER] mc_inline_miss 3
[RUBY_DEBUG_COUNTER] mc_global_hit 23
[RUBY_DEBUG_COUNTER] mc_global_miss 273
[RUBY_DEBUG_COUNTER] mc_global_state_miss 3
[RUBY_DEBUG_COUNTER] mc_class_serial_miss 0
[RUBY_DEBUG_COUNTER] mc_cme_complement 0
[RUBY_DEBUG_COUNTER] mc_cme_complement_hit 0
[RUBY_DEBUG_COUNTER] mc_search_super 1384
[RUBY_DEBUG_COUNTER] ivar_get_hit 0
[RUBY_DEBUG_COUNTER] ivar_get_miss 0
[RUBY_DEBUG_COUNTER] ivar_set_hit 0
[RUBY_DEBUG_COUNTER] ivar_set_miss 0
[RUBY_DEBUG_COUNTER] ivar_get 431
[RUBY_DEBUG_COUNTER] ivar_set 465
* mc_... is related to method caching.
* ivar_... is related to instance variable accesses.
* compare with dtrace/system tap features, there are completely
no performacne penalties when it is disabled.
* This feature is supported only on __GNUC__ compilers.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57676 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
