Hi, Mads and Erik,
If OOM happens, Are those heap resources still can be reclaimed if we call v8::V8::Dispose()? Or there would be memory leak until we exit the process? Cheers~ Xiang On Wed, Nov 25, 2009 at 4:31 PM, Xiang Zhong <[email protected]> wrote: > Hi， Erik， > > Yes, you are right. > > I confuse setting heap limit with setting stack limit, which have to be set > seperately by the doc for the latter. > > thanks~ > > /** > * A set of constraints that specifies the limits of the runtime's memory > use. > * You must set the heap size before initializing the VM - the size cannot > be > * adjusted after the VM is initialized. > * > * If you are using threads then you should hold the *V8::Locker lock*while > * setting the stack limit and you must *set a non-default stack limit > separately* > * for each thread. > */ > class V8EXPORT ResourceConstraints { > > > > On Wed, Nov 25, 2009 at 4:22 PM, Erik Corry <[email protected]> wrote: > >> >> 2009/11/25 Xiang Zhong <[email protected]>: >> > Suppose they speficy heap constraint seperately >> > with SetResourceConstraints(ResourceConstraints* constraints) >> >> You can only use that interface once to set the heap size (and you >> have to do it before initializing V8). It applies to all threads. >> >> > >> > >> > On Wed, Nov 25, 2009 at 4:15 PM, Xiang Zhong <[email protected]> >> wrote: >> >> >> >> Hi, Mads， >> >> >> >> Yeah, I see. Thanks for your answer. >> >> Another question :-), if we enable multi-thread by v8::V8::Locker, will >> >> other threads dead too if one thread encounter OOM? >> >> >> >> Sincerely~ >> >> Xiang >> >> >> >> >> >> >> >> On Wed, Nov 25, 2009 at 3:54 PM, Mads Sig Ager <[email protected]> >> wrote: >> >>> >> >>> Nothing like that exists. We do not know in advance that we are going >> >>> to run out of memory. >> >>> >> >>> -- Mads >> >>> >> >>> On Wed, Nov 25, 2009 at 8:52 AM, Xiang Zhong <[email protected]> >> wrote: >> >>> > >> >>> > Hi, Mads, >> >>> > >> >>> > Is there a way that the caller can get notified before an OOM >> situation >> >>> > happen? >> >>> > If that is possible, the caller can call >> v8::V8::TerminateExecution() >> >>> > beforehand, and dispose the global object in time to free memory. >> >>> > That will save v8 from being dead or crashing. >> >>> > >> >>> > We can hook a callback through SetGlobalGCEpilogueCallback() after >> GC >> >>> > happen, if we can get a flag some like " >> >>> > GC_FAIL_GOING_TO_OUT_OF_MEMORY", >> >>> > then it is possible to check the flag and terminate in time. >> >>> > Does there exist something like that? >> >>> > >> >>> > Wishes~ >> >>> > Xiang >> >>> > >> >>> > On Wed, Nov 25, 2009 at 3:35 PM, Mads Sig Ager <[email protected]> >> >>> > wrote: >> >>> >> >> >>> >> An out of memory situation can leave the VM in an inconsistent >> state, >> >>> >> so it is not possible to continue. It is therefore the expected >> >>> >> behavior that we cannot continue here. >> >>> >> >> >>> >> Cheers, -- Mads >> >>> >> >> >>> >> On Wed, Nov 25, 2009 at 3:45 AM, Xiang <[email protected]> wrote: >> >>> >> > >> >>> >> > Hi, All, >> >>> >> > >> >>> >> > I have declared v8::V8::IgnoreOutOfMemoryException(), and the >> out >> >>> >> > of >> >>> >> > memory exception is caught by trycatch as expected. >> >>> >> > >> >>> >> > However, after disposing the current context, we can't create a >> new >> >>> >> > context. >> >>> >> > >> >>> >> > The handle is empty. >> >>> >> > >> >>> >> > Please check the following UＴ case: >> >>> >> > >> >>> >> > Reproduction steps >> >>> >> > --------------------------------------------------------- >> >>> >> > Please add the following case to test-api.cc, >> >>> >> > >> >>> >> > When creating a new context, >> >>> >> > v8::Persistent<v8::Context> context = v8::Context::New(0, >> >>> >> > v8::Handle<v8::ObjectTemplate>(), v8::Handle<v8::Value>()); >> >>> >> > It will fail >> >>> >> > >> >>> >> > TEST(CreateNewContextAfterOutOfMemory) { >> >>> >> > // It's not possible to read a snapshot into a heap with >> >>> >> > different >> >>> >> > dimensions. >> >>> >> > if (v8::internal::Snapshot::IsEnabled()) return; >> >>> >> > // Set heap limits. >> >>> >> > static const int K = 1024; >> >>> >> > v8::ResourceConstraints constraints; >> >>> >> > constraints.set_max_young_space_size(256 * K); >> >>> >> > constraints.set_max_old_space_size(4 * K * K); >> >>> >> > v8::SetResourceConstraints(&constraints); >> >>> >> > >> >>> >> > // Execute a script that causes out of memory. >> >>> >> > v8::HandleScope scope; >> >>> >> > { >> >>> >> > LocalContext context; >> >>> >> > v8::V8::IgnoreOutOfMemoryException(); >> >>> >> > Local<Script> script = >> >>> >> > >> Script::Compile(String::New(js_code_causing_out_of_memory)); >> >>> >> > Local<Value> result = script->Run(); >> >>> >> > >> >>> >> > // Check for out of memory state. >> >>> >> > CHECK(result.IsEmpty()); >> >>> >> > CHECK(context->HasOutOfMemoryException()); >> >>> >> > } >> >>> >> > >> >>> >> > { >> >>> >> > v8::Persistent<v8::Context> context = v8::Context::New(0, >> >>> >> > v8::Handle<v8::ObjectTemplate>(), v8::Handle<v8::Value>()); >> >>> >> > >> >>> >> > >> >>> >> > //Check here! >> >>> >> > >> >>> >> > //I think we should be allowed to create a new context >> >>> >> > //And the Handle should not be empty >> >>> >> > CHECK(!context.IsEmpty()); >> >>> >> > context.Dispose(); >> >>> >> > context.Clear(); >> >>> >> > } >> >>> >> > } >> >>> >> > > >> >>> >> > >> >>> > >> >>> > >> >>> > >> >>> > > >> >>> > >> >>> >> >>> >> >> >> > >> > >> > > >> > >> >> >> >> > --~--~---------~--~----~------------~-------~--~----~ v8-dev mailing list [email protected] http://groups.google.com/group/v8-dev -~----------~----~----~----~------~----~------~--~---
