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)
On ar_table, Do not keep a full-length hash value (FLHV, 8 bytes)
but keep a 1 byte hint from a FLHV (lowest byte of FLHV).
An ar_table only contains at least 8 entries, so hints consumes
8 bytes at most. We can store hints in RHash::ar_hint.
On 32bit CPU, we use 4 entries ar_table.
The advantages:
* We don't need to keep FLHV so ar_table only consumes
16 bytes (VALUEs of key and value) * 8 entries = 128 bytes.
* We don't need to scan ar_table, but only need to check hints
in many cases. Especially we don't need to access ar_table
if there is no match entries (in many cases).
It will increase memory cache locality.
The disadvantages:
* This technique can increase `#eql?` time because hints can
conflicts (in theory, it conflicts once in 256 times).
It can introduce incompatibility if there is a object x where
x.eql? returns true even if hash values are different.
I believe we don't need to care such irregular case.
* We need to re-calculate FLHV if we need to switch from ar_table
to st_table (e.g. exceeds 8 entries).
It also can introduce incompatibility, on mutating key objects.
I believe we don't need to care such irregular case too.
Add new debug counters to measure the performance:
* artable_hint_hit - hint is matched and eql?#=>true
* artable_hint_miss - hint is not matched but eql?#=>false
* artable_hint_notfound - lookup counts
Shared arrays created by Array#dup and so on points
a shared_root object to manage lifetime of Array buffer.
However, sometimes shared_root is called only shared so
it is confusing. So I fixed these wording "shared" to "shared_root".
* RArray::heap::aux::shared -> RArray::heap::aux::shared_root
* ARY_SHARED() -> ARY_SHARED_ROOT()
* ARY_SHARED_NUM() -> ARY_SHARED_ROOT_REFCNT()
Also, add some debug_counters to count shared array objects.
* ary_shared_create: shared ary by Array#dup and so on.
* ary_shared: finished in shard.
* ary_shared_root_occupied: shared_root but has only 1 refcnt.
The number (ary_shared - ary_shared_root_occupied) is meaningful.
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
Add counters to count ccf (call cache fastpath) usage.
These counters will help which kind of method dispatch
is important to optimize.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@67336 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* internal.h: rename the following names:
* li_table -> ar_table. "li" means linear (from linear search),
but we use the word "array" (from data layout).
* RHASH_ARRAY -> RHASH_AR_TABLE. AR_TABLE is more clear.
* rb_hash_array_* -> rb_hash_ar_table_*.
* RHASH_TABLE_P() -> RHASH_ST_TABLE_P(). more clear.
* RHASH_CLEAR() -> RHASH_ST_CLEAR().
* hash.c: rename "linear_" prefix functions to "ar_" prefix.
* hash.c (linear_init_table): rename to ar_alloc_table.
* debug_counter.h: rename obj_hash_array to obj_hash_ar.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@66390 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* hash.c, internal.h: support theap for small Hash.
Introduce RHASH_ARRAY (li_table) besides st_table and small Hash
(<=8 entries) are managed by an array data structure.
This array data can be managed by theap.
If st_table is needed, then converting array data to st_table data.
For st_table using code, we prepare "stlike" APIs which accepts hash value
and are very similar to st_ APIs.
This work is based on the GSoC achievement
by tacinight <tacingiht@gmail.com> and refined by ko1.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65454 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* variable.c: now instance variable space has theap supports.
obj_ivar_heap_alloc() tries to acquire memory from theap.
* debug_counter.h: add some counters for theap.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65451 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* transient_heap.c, transient_heap.h: implement TransientHeap (theap).
theap is designed for Ruby's object system. theap is like Eden heap
on generational GC terminology. theap allocation is very fast because
it only needs to bump up pointer and deallocation is also fast because
we don't do anything. However we need to evacuate (Copy GC terminology)
if theap memory is long-lived. Evacuation logic is needed for each type.
See [Bug #14858] for details.
* array.c: Now, theap for T_ARRAY is supported.
ary_heap_alloc() tries to allocate memory area from theap. If this trial
sccesses, this array has theap ptr and RARRAY_TRANSIENT_FLAG is turned on.
We don't need to free theap ptr.
* ruby.h: RARRAY_CONST_PTR() returns malloc'ed memory area. It menas that
if ary is allocated at theap, force evacuation to malloc'ed memory.
It makes programs slow, but very compatible with current code because
theap memory can be evacuated (theap memory will be recycled).
If you want to get transient heap ptr, use RARRAY_CONST_PTR_TRANSIENT()
instead of RARRAY_CONST_PTR(). If you can't understand when evacuation
will occur, use RARRAY_CONST_PTR().
(re-commit of r65444)
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65449 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* variable.c: now instance variable space has theap supports.
obj_ivar_heap_alloc() tries to acquire memory from theap.
* debug_counter.h: add some counters for theap.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65446 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* transient_heap.c, transient_heap.h: implement TransientHeap (theap).
theap is designed for Ruby's object system. theap is like Eden heap
on generational GC terminology. theap allocation is very fast because
it only needs to bump up pointer and deallocation is also fast because
we don't do anything. However we need to evacuate (Copy GC terminology)
if theap memory is long-lived. Evacuation logic is needed for each type.
See [Bug #14858] for details.
* array.c: Now, theap for T_ARRAY is supported.
ary_heap_alloc() tries to allocate memory area from theap. If this trial
sccesses, this array has theap ptr and RARRAY_TRANSIENT_FLAG is turned on.
We don't need to free theap ptr.
* ruby.h: RARRAY_CONST_PTR() returns malloc'ed memory area. It menas that
if ary is allocated at theap, force evacuation to malloc'ed memory.
It makes programs slow, but very compatible with current code because
theap memory can be evacuated (theap memory will be recycled).
If you want to get transient heap ptr, use RARRAY_CONST_PTR_TRANSIENT()
instead of RARRAY_CONST_PTR(). If you can't understand when evacuation
will occur, use RARRAY_CONST_PTR().
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@65444 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* debug_counter.h: add debug counters to count frame state transitions:
* frame_R2R: Ruby frame to Ruby frame
* frame_R2C: Ruby frame to C frame
* frame_C2C: C frame to C frame
* frame_C2R: C frame to Ruby frame
* vm_insnhelper.c (vm_push_frame): ditto.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64871 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
* vm_core.h: rename absolute_path to realpath because it is expected name.
external APIs (#absolute_path methods) are remained.
* vm_core.h: remove rb_iseq_location_struct::path and
rb_iseq_location_struct::absolute_path and introduce pathobj.
if given path equals to given absolute_path (and most of case
it is true), pathobj is simply given path String. If it is not same,
pathobj is Array and pathobj[0] is path and pathobj[1] is realpath.
This size optimization reduce 8 bytes and
sizeof(struct rb_iseq_constant_body) is 200 bytes -> 192 bytes
on 64bit CPU.
To support this change, the following functions are introduced:
* pathobj_path() (defined in vm_core.h)
* pathobj_realpath() (ditto)
* rb_iseq_path() (decl. in vm_core.h)
* rb_iseq_realpath() (ditto)
* rb_iseq_pathobj_new() (ditto)
* rb_iseq_pathobj_set() (ditto)
* vm_core.h (rb_binding_t): use pathobj instead of path. If binding
is given at eval methods, realpath (absolute_path) was caller's
realpath. However, they should use binding's realpath.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58979 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* debug_counter.h: add the following counters:
* lvar_get: counter for lvar get.
* lvar_get_dynamic: counter for lvar get from upper frames.
* lvar_set: coutner for lvar set.
* lvar_set_dynamic: coutner for lvar set from upper frames.
* lvar_set_slowpath: counter for lavr set using slowpath.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58977 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* debug_counter.h: add the following counters to measure object types.
obj_free: freed count
obj_str_ptr: freed count of Strings they have extra buff.
obj_str_embed: freed count of Strings they don't have extra buff.
obj_str_shared: freed count of Strings they have shared extra buff.
obj_str_nofree: freed count of Strings they are marked as nofree.
obj_str_fstr: freed count of Strings they are marked as fstr.
obj_ary_ptr: freed count of Arrays they have extra buff.
obj_ary_embed: freed count of Arrays they don't have extra buff.
obj_obj_ptr: freed count of Objects (T_OBJECT) they have extra buff.
obj_obj_embed: freed count of Objects they don't have extra buff.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58865 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
Aaron Patterson
Koichi Sasada
Koichi Sasada
Lourens Naudé
k0kubun
kazu
ko1
nobu