+Peter Marshall <petermarsh...@chromium.org> On Wed, Nov 6, 2019 at 8:58 AM Darin Dimitrov <darin.dimit...@gmail.com> wrote:
> I am trying to collect function execution data using the CpuProfiler class. > > I ran the following test (taken from here > https://github.com/v8/v8/blob/master/test/cctest/test-cpu-profiler.cc#L677 > ): > > const char* src = > "function loop(timeout) {\n" > " this.mmm = 0;\n" > " var start = Date.now();\n" > " do {\n" > " var n = 1000;\n" > " while(n > 1) {\n" > " n--;\n" > " this.mmm += n * n * n;\n" > " }\n" > " } while (Date.now() - start < timeout);\n" > "}\n" > "function delay() { loop(10); }\n" > "function bar() { delay(); }\n" > "function baz() { delay(); }\n" > "function foo() {\n" > " delay();\n" > " bar();\n" > " delay();\n" > " baz();\n" > "}\n" > "function start(duration) {\n" > " var start = Date.now();\n" > " do {\n" > " foo();\n" > " } while (Date.now() - start < duration);\n" > "}\n"; > > Script::Compile(context, v8::String::NewFromUtf8(isolate, src). > ToLocalChecked()).ToLocalChecked()->Run(context).ToLocalChecked(); > Local<v8::Function> startFunc = context->Global()->Get(context, v8::String > ::NewFromUtf8(isolate, "start").ToLocalChecked()).ToLocalChecked().As<v8:: > Function>(); > > Local<v8::String> title = v8::String::NewFromUtf8(isolate, "my_trace"). > ToLocalChecked(); > CpuProfiler* profiler = CpuProfiler::New(isolate); > profiler->StartProfiling(title, false); > > Local<Value> result; > Local<Value> args[] = { Number::New(isolate, 200) }; > assert(startFunc->Call(context, context->Global(), 1, args).ToLocal(& > result)); > > const CpuProfile* profile = profiler->StopProfiling(title); > const CpuProfileNode* root = profile->GetTopDownRoot(); > int count = root->GetChildrenCount(); > for (int i = 0; i < count; ++i) { > const CpuProfileNode* child = root->GetChild(i); > v8::String::Utf8Value str(isolate, child->GetFunctionName()); > const char* funcName = *str; > printf("%s\n", funcName); > } > > > > The root CpuProfileNode contains only a single child element called > "(program)". > > If I execute the same code on Android, I correctly get the following child > functions: "(program)", "start" and "(garbage collector)". > > Do you have any idea what might be wrong with the CpuProfiler class in v8 > in jitless mode? Is CpuProfiler the correct class to use to collect > function execution times or is there some newer method? > > -- > -- > v8-users mailing list > v8-users@googlegroups.com > http://groups.google.com/group/v8-users > --- > You received this message because you are subscribed to the Google Groups > "v8-users" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to v8-users+unsubscr...@googlegroups.com. > To view this discussion on the web visit > https://groups.google.com/d/msgid/v8-users/798f9464-88a1-464f-8fb8-6aa223ce5e57%40googlegroups.com > <https://groups.google.com/d/msgid/v8-users/798f9464-88a1-464f-8fb8-6aa223ce5e57%40googlegroups.com?utm_medium=email&utm_source=footer> > . > -- -- v8-users mailing list v8-users@googlegroups.com http://groups.google.com/group/v8-users --- You received this message because you are subscribed to the Google Groups "v8-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to v8-users+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/v8-users/CAH3p7oP%3DOKA8UCZgxFrLehh3ULbWGF-FU0%2BdnXop2%3DuW574k%2Bw%40mail.gmail.com.
