I recently had a problem where a Persistent was being initialised in one Isolate which was then disposed. I accidentally kept an initialised Persistent around and got an immediate crash when calling Persistent Reset after creating a 2nd Isolate. In my case I was neglecting to Reset properly one Persistent handle. The weak callback was properly invoked, and on destruction I was also walking the heap for tagged Persistent objects (isolate->VisitHandlesWithClassIds) but the culprit was the lack of one single Persistent Reset. Maybe worth a look. El miércoles, 31 de agosto de 2022 a las 19:56:02 UTC+2, loude...@gmail.com escribió:
> A mutex around our persistent creation alone didn't solve this problem. > Removing v8::Persistent and replacing them with v8::Global is not ideal, > since we reuse these Persistent objects across multiple contexts to cache > common function/object templates. > > On Friday, August 26, 2022 at 9:17:00 AM UTC-7 loude...@gmail.com wrote: > >> Oh, single-threaded. I would have expected v8 to use a mutex around >> their persistent (global handle) management. I'll try a mutex on my side >> and see if that resolves the issue. Thanks for your help. 🤞 >> >> On Fri, Aug 26, 2022 at 12:52 AM dinf...@chromium.org < >> dinf...@chromium.org> wrote: >> >>> Hi, >>> >>> Those persistent/global handles are single-threaded only, could it be >>> that you allocate such handles from multiple threads? >>> >>> There is also v8::Global which Reset()s itself in the destructor >>> automatically. We would even like to remove v8::Persistent entirely at some >>> point (see >>> https://bugs.chromium.org/p/v8/issues/detail?id=12915&q=v8%3A%3APersistent&can=2 >>> ). >>> >>> Cheers, >>> Dominik >>> >>> On Friday, August 26, 2022 at 12:23:12 AM UTC+2 loude...@gmail.com >>> wrote: >>> >>>> Yeah, we are out of date and I will attempt to upgrade soon. But, I do >>>> think there's a threading issue here that's very intermittent. I did read >>>> other posts that describe problems if you don't call Reset on the >>>> persistent object. See any problems here? >>>> >>>> typedef std::pair<DataDeleterP*, utils::PersistentP<v8::Object> > >>>> PeristentWeakDataPair; >>>> typedef v8::WeakCallbackInfo<PeristentWeakDataPair> >>>> PersistentWeakData; >>>> >>>> static >>>> utils::PersistentP<v8::Object> makePersistent(v8::Isolate *isolate, >>>> v8::Handle<v8::Object> object, DataDeleterP* dataDeleterPP, >>>> PersistentWeakData::Callback callback) { >>>> utils::PersistentP<v8::Object> persistentObjP(new >>>> PERSISTENT_BASE(v8::Object)(isolate, object)); >>>> persistentObjP->SetWeak(new >>>> PeristentWeakDataPair(dataDeleterPP, persistentObjP), callback, >>>> v8::WeakCallbackType::kParameter); >>>> return persistentObjP; >>>> } >>>> >>>> static >>>> void releasePersistent (const PersistentWeakData& data) >>>> { >>>> PeristentWeakDataPair* paramPairP = data.GetParameter(); >>>> >>>> delete paramPairP->first; >>>> paramPairP->second->Reset(); >>>> paramPairP->second.reset(); >>>> delete paramPairP; >>>> >>>> #ifdef ADOBE_V8_DEBUG_V8_ALLOCATIONS >>>> DecrementV8AllocCount(); >>>> #endif >>>> } >>>> >>>> On Thursday, August 25, 2022 at 6:02:02 AM UTC-7 les...@chromium.org >>>> wrote: >>>> >>>>> This is unfortunately too little detail to go on, my best guess would >>>>> be that you're passing in an invalid Isolate pointer (something to do >>>>> with >>>>> lifetimes in the embedder?). Also note that you're using a 1-year old >>>>> version of V8. >>>>> >>>>> On Wednesday, August 24, 2022 at 10:42:51 PM UTC+2 loude...@gmail.com >>>>> wrote: >>>>> >>>>>> Anyone?? >>>>>> >>>>>> On Wednesday, June 15, 2022 at 5:25:20 PM UTC-7 loude...@gmail.com >>>>>> wrote: >>>>>> >>>>>>> Any ideas why I'm seeing an intermittent crash here? It happens >>>>>>> during a stress test for Adobe Character Animator (v8 >>>>>>> version: 9.4.146.24). This call is made 1000s of times in our app and >>>>>>> occasionally there's a crash. >>>>>>> >>>>>>> Character Animator >>>>>>> (Beta).exe!v8::internal::GlobalHandles::Create(class >>>>>>> v8::internal::Object) >>>>>>> Unknown >>>>>>> Character Animator >>>>>>> (Beta).exe!v8::internal::GlobalHandles::Create(unsigned __int64) >>>>>>> Unknown >>>>>>> Character Animator (Beta).exe!v8::V8::GlobalizeReference(class >>>>>>> v8::internal::Isolate *,unsigned __int64 *) Unknown >>>>>>> > [Inline Frame] Character Animator >>>>>>> (Beta).exe!v8::PersistentBase<v8::Object>::New(v8::Isolate *) Line >>>>>>> 10971 >>>>>>> C++ >>>>>>> [Inline Frame] Character Animator >>>>>>> (Beta).exe!v8::Persistent<v8::Object,adobe_v8::utils::PersistentTraitsT<v8::Object>>::{ctor}(v8::Isolate >>>>>>> >>>>>>> *) Line 682 C++ >>>>>>> Character Animator >>>>>>> (Beta).exe!adobe_v8::makePersistent(v8::Isolate * isolate, >>>>>>> v8::Local<v8::Object> object, boost::shared_ptr<void> * dataDeleterPP, >>>>>>> void(*)(const v8::WeakCallbackInfo<std::pair<boost::shared_ptr<void> >>>>>>> *,adobe_v8::utils::PersistentP<v8::Object>>> &) callback) Line 1508 >>>>>>> C++ >>>>>>> Character Animator >>>>>>> (Beta).exe!adobe_v8::CreatePersistentData(v8::Isolate * inIsolateP, >>>>>>> v8::Local<v8::Object> obj, boost::shared_ptr<void> dataDeleterP) Line >>>>>>> 1548 >>>>>>> C++ >>>>>>> Character Animator >>>>>>> (Beta).exe!adobe_v8::AttachPersistentDataToInstance(v8::Isolate * >>>>>>> inIsolateP, v8::Local<v8::Object> instance, void * dataP, >>>>>>> boost::shared_ptr<void> dataDeleterP) Line 1583 C++ >>>>>>> >>>>>>> The thread 0x8c4 has exited with code 0 (0x0). >>>>>>> <31172> <ExportStageVideoTask> <5> Number of export render threads: 4 >>>>>>> Exception thrown at 0x000000014105BACA in Character Animator >>>>>>> (Beta).exe: 0xC0000005: Access violation reading location >>>>>>> 0xFFFFFFFFFFFFFFFF. >>>>>>> >>>>>> -- >>> -- >>> v8-users mailing list >>> v8-u...@googlegroups.com >>> http://groups.google.com/group/v8-users >>> --- >>> You received this message because you are subscribed to a topic in the >>> Google Groups "v8-users" group. >>> To unsubscribe from this topic, visit >>> https://groups.google.com/d/topic/v8-users/Pg5OPm7uPFY/unsubscribe. >>> To unsubscribe from this group and all its topics, send an email to >>> v8-users+u...@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/v8-users/a95e8264-8f5a-4b5c-9e14-410982a61683n%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/v8-users/a95e8264-8f5a-4b5c-9e14-410982a61683n%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. 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