Extended maintenance of Ruby 1.9.3 ended on February 23, 2015. Read more
The GC profiler provides access to information on GC runs including time, length and object space size.
Example:
GC::Profiler.enable require 'rdoc/rdoc' puts GC::Profiler.result GC::Profiler.disable
See also GC.count, GC.malloc_allocated_size and GC.malloc_allocations
Clears the GC profiler data.
static VALUE
gc_profile_clear(void)
{
rb_objspace_t *objspace = &rb_objspace;
MEMZERO(objspace->profile.record, gc_profile_record, objspace->profile.size);
objspace->profile.count = 0;
return Qnil;
}
Stops the GC profiler.
static VALUE
gc_profile_disable(void)
{
rb_objspace_t *objspace = &rb_objspace;
objspace->profile.run = FALSE;
return Qnil;
}
Starts the GC profiler.
static VALUE
gc_profile_enable(void)
{
rb_objspace_t *objspace = &rb_objspace;
objspace->profile.run = TRUE;
return Qnil;
}
The current status of GC profile mode.
static VALUE
gc_profile_enable_get(VALUE self)
{
rb_objspace_t *objspace = &rb_objspace;
return objspace->profile.run ? Qtrue : Qfalse;
}
Writes the GC::Profiler#result to $stdout or the given IO object.
static VALUE
gc_profile_report(int argc, VALUE *argv, VALUE self)
{
VALUE out;
if (argc == 0) {
out = rb_stdout;
}
else {
rb_scan_args(argc, argv, "01", &out);
}
rb_io_write(out, gc_profile_result());
return Qnil;
}
Returns a profile data report such as:
GC 1 invokes.
Index Invoke Time(sec) Use Size(byte) Total Size(byte) Total Object GC time(ms)
1 0.012 159240 212940 10647 0.00000000000001530000
static VALUE
gc_profile_result(void)
{
rb_objspace_t *objspace = &rb_objspace;
VALUE record;
VALUE result;
int i, index;
record = gc_profile_record_get();
if (objspace->profile.run && objspace->profile.count) {
result = rb_sprintf("GC %d invokes.\n", NUM2INT(gc_count(0)));
index = 1;
rb_str_cat2(result, "Index Invoke Time(sec) Use Size(byte) Total Size(byte) Total Object GC Time(ms)\n");
for (i = 0; i < (int)RARRAY_LEN(record); i++) {
VALUE r = RARRAY_PTR(record)[i];
#if !GC_PROFILE_MORE_DETAIL
if (rb_hash_aref(r, ID2SYM(rb_intern("GC_IS_MARKED")))) {
#endif
rb_str_catf(result, "%5d %19.3f %20"PRIuSIZE" %20"PRIuSIZE" %20"PRIuSIZE" %30.20f\n",
index++, NUM2DBL(rb_hash_aref(r, ID2SYM(rb_intern("GC_INVOKE_TIME")))),
(size_t)NUM2SIZET(rb_hash_aref(r, ID2SYM(rb_intern("HEAP_USE_SIZE")))),
(size_t)NUM2SIZET(rb_hash_aref(r, ID2SYM(rb_intern("HEAP_TOTAL_SIZE")))),
(size_t)NUM2SIZET(rb_hash_aref(r, ID2SYM(rb_intern("HEAP_TOTAL_OBJECTS")))),
NUM2DBL(rb_hash_aref(r, ID2SYM(rb_intern("GC_TIME"))))*1000);
#if !GC_PROFILE_MORE_DETAIL
}
#endif
}
#if GC_PROFILE_MORE_DETAIL
rb_str_cat2(result, "\n\n");
rb_str_cat2(result, "More detail.\n");
rb_str_cat2(result, "Index Allocate Increase Allocate Limit Use Slot Have Finalize Mark Time(ms) Sweep Time(ms)\n");
index = 1;
for (i = 0; i < (int)RARRAY_LEN(record); i++) {
VALUE r = RARRAY_PTR(record)[i];
rb_str_catf(result, "%5d %17"PRIuSIZE" %17"PRIuSIZE" %9"PRIuSIZE" %14s %25.20f %25.20f\n",
index++, (size_t)NUM2SIZET(rb_hash_aref(r, ID2SYM(rb_intern("ALLOCATE_INCREASE")))),
(size_t)NUM2SIZET(rb_hash_aref(r, ID2SYM(rb_intern("ALLOCATE_LIMIT")))),
(size_t)NUM2SIZET(rb_hash_aref(r, ID2SYM(rb_intern("HEAP_USE_SLOTS")))),
rb_hash_aref(r, ID2SYM(rb_intern("HAVE_FINALIZE")))? "true" : "false",
NUM2DBL(rb_hash_aref(r, ID2SYM(rb_intern("GC_MARK_TIME"))))*1000,
NUM2DBL(rb_hash_aref(r, ID2SYM(rb_intern("GC_SWEEP_TIME"))))*1000);
}
#endif
}
else {
result = rb_str_new2("");
}
return result;
}
The total time used for garbage collection in milliseconds
static VALUE
gc_profile_total_time(VALUE self)
{
double time = 0;
rb_objspace_t *objspace = &rb_objspace;
size_t i;
if (objspace->profile.run && objspace->profile.count) {
for (i = 0; i < objspace->profile.count; i++) {
time += objspace->profile.record[i].gc_time;
}
}
return DBL2NUM(time);
}