This happens on the Hub every couple of hours.
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: <--- Last few GCs --->
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: 0.[943733:0x7f919800d000] 8078400 ms: Mark-Compact (reduce) 1399.3 (1424.2) -> 1398.7 (1424.8) MB, pooled: 0 MB, 1821.78 / 0.00 ms (+ 87.8 ms in 0 steps since start of marking, biggest step 0.0 ms, walltime since start of marking 2668 ms) (average mu = 0.[943733:0x7f919800d000] 8081853 ms: Mark-Compact (reduce) 1399.7 (1424.8) -> 1399.1 (1425.5) MB, pooled: 0 MB, 2034.97 / 0.00 ms (+ 67.1 ms in 0 steps since start of marking, biggest step 0.0 ms, walltime since start of marking 2910 ms) (average mu = 0.
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: <--- JS stacktrace --->
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: #
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: # Fatal JavaScript out of memory: Reached heap limit
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: #
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: ==== C stack trace ===============================
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::base::debug::StackTrace::StackTrace()+0x16) [0x7f91ce0e7206]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(+0x140ab3b) [0x7f91cd20ab3b]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::base::FatalOOM(v8::base::OOMType, char const*)+0x3b) [0x7f91ce0d3f0b]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(+0x181e085) [0x7f91cd61e085]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::internal::V8::FatalProcessOutOfMemory(v8::internal::Isolate*, char const*, v8::OOMDetails const&)+0x355) [0x7f91cd61e3e5]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(+0x1a46dd7) [0x7f91cd846dd7]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::internal::Heap::CollectGarbage(v8::internal::AllocationSpace, v8::internal::GarbageCollectionReason, v8::GCCallbackFlags)+0x2bd) [0x7f91cd85e89d]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::internal::HeapAllocator::AllocateRawWithLightRetrySlowPath(int, v8::internal::AllocationType, v8::internal::AllocationOrigin, v8::internal::AllocationAlignment)+0xb1b) [0x7f91cd8371db]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::internal::HeapAllocator::AllocateRawWithRetryOrFailSlowPath(int, v8::internal::AllocationType, v8::internal::AllocationOrigin, v8::internal::AllocationAlignment)+0x25) [0x7f91cd837875]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::internal::Factory::AllocateRaw(int, v8::internal::AllocationType, v8::internal::AllocationAlignment)+0xcb) [0x7f91cd81450b]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::internal::FactoryBase<v8::internal::Factory>::AllocateRawFixedArray(int, v8::internal::AllocationType)+0x2c) [0x7f91cd80577c]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::internal::Factory::CopyPropertyArrayAndGrow(v8::internal::Handle<v8::internal::PropertyArray>, int)+0x37) [0x7f91cd81f3d7]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::internal::JSObject::MigrateToMap(v8::internal::Isolate*, v8::internal::Handle<v8::internal::JSObject>, v8::internal::Handle<v8::internal::Map>, int)+0x17c0) [0x7f91cda38670]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::internal::LookupIterator::ApplyTransitionToDataProperty(v8::internal::Handle<v8::internal::JSReceiver>)+0x181) [0x7f91cda97951]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::internal::Object::TransitionAndWriteDataProperty(v8::internal::LookupIterator*, v8::internal::Handle<v8::internal::Object>, v8::internal::PropertyAttributes, v8::Maybe<v8::internal::ShouldThrow>, v8::internal::StoreOrigin)+0x71) [0x7f91cdaafd51]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::internal::Runtime::SetObjectProperty(v8::internal::Isolate*, v8::internal::Handle<v8::internal::Object>, v8::internal::Handle<v8::internal::Object>, v8::internal::Handle<v8::internal::Object>, v8::internal::StoreOrigin, v8::Maybe<v8::internal::ShouldThrow>)+0x1ea) [0x7f91cdc284aa]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libnode.so.127(v8::Object::Set(v8::Local<v8::Context>, v8::Local<v8::Value>, v8::Local<v8::Value>)+0x114) [0x7f91cd6326f4]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libscript-engine.so(ScriptValueV8Wrapper::setProperty(QString const&, ScriptValue const&, QFlags<ScriptValue::PropertyFlag> const&)+0x24f) [0x7f91d279886f]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libentities.so(EntityItemProperties::copyToScriptValue(ScriptEngine*, bool, bool, bool, std::bitset<15ul>) const+0x3aa8) [0x7f91d303e2c8]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libentities.so(EntityItemNonDefaultPropertiesToScriptValue(ScriptEngine*, EntityItemProperties const&)+0x28) [0x7f91d2ff07c8]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libentities.so(RecurseOctreeToJSONOperator::processEntity(std::shared_ptr<EntityItem> const&)+0x7b) [0x7f91d2fdb37b]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libentities.so(RecurseOctreeToJSONOperator::postRecursion(std::shared_ptr<OctreeElement> const&)+0xa7) [0x7f91d2fdb767]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::recurseElementWithOperator(std::shared_ptr<OctreeElement> const&, RecurseOctreeOperator*, int)+0x52) [0x7f91d2d43792]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/libentities.so(EntityTree::writeToJSON(QString&, std::shared_ptr<OctreeElement> const&)+0x1f3) [0x7f91d2f8df53]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::toJSONString(QString&, std::shared_ptr<OctreeElement> const&)+0x136) [0x7f91d2d449b6]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::toJSON(QByteArray*, std::shared_ptr<OctreeElement> const&, bool)+0x3c) [0x7f91d2d44d3c]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::writeToJSONFile(char const*, std::shared_ptr<OctreeElement> const&, bool)+0x4a) [0x7f91d2d493ea]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(Octree::writeToFile(char const*, std::shared_ptr<OctreeElement> const&, QString)+0x3a7) [0x7f91d2d49a47]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(OctreePersistThread::persist()+0x1d6) [0x7f91d2d62176]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /opt/overte/lib/liboctree.so(OctreePersistThread::process()+0xac) [0x7f91d2d6276c]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libQt5Core.so.5(+0x31d357) [0x7f91d1d1d357]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libQt5Core.so.5(QObject::event(QEvent*)+0x18b) [0x7f91d1d0c03b]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libQt5Core.so.5(QCoreApplication::notifyInternal2(QObject*, QEvent*)+0xf5) [0x7f91d1cde425]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libQt5Core.so.5(QTimerInfoList::activateTimers()+0x3d1) [0x7f91d1d3a821]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libQt5Core.so.5(+0x33b174) [0x7f91d1d3b174]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libglib-2.0.so.0(+0x5c3c5) [0x7f91cb3033c5]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libglib-2.0.so.0(+0x5e5f7) [0x7f91cb3055f7]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libglib-2.0.so.0(g_main_context_iteration+0x30) [0x7f91cb305d60]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libQt5Core.so.5(QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>)+0x6d) [0x7f91d1d3b4ad]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libQt5Core.so.5(QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>)+0x132) [0x7f91d1cdcdc2]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libQt5Core.so.5(QThread::exec()+0x60) [0x7f91d1adda90]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libQt5Core.so.5(+0xded21) [0x7f91d1aded21]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libc.so.6(+0x92b7b) [0x7f91d129eb7b]
Jul 11 20:39:34 domain-beta.overte.org assignment-client[943733]: /lib/x86_64-linux-gnu/libc.so.6(+0x1107f8) [0x7f91d131c7f8]
Jul 11 20:39:36 domain-beta.overte.org systemd[1]: overte-entity-server@Overte_Hub.service: Main process exited, code=killed, status=5/TRAP
Jul 11 20:39:36 domain-beta.overte.org systemd[1]: overte-entity-server@Overte_Hub.service: Failed with result 'signal'.
Jul 11 20:39:36 domain-beta.overte.org systemd[1]: overte-entity-server@Overte_Hub.service: Consumed 35min 53.712s CPU time, 4.1G memory peak, 4.8G memory swap peak.
Jul 11 20:39:36 domain-beta.overte.org systemd[1]: overte-entity-server@Overte_Hub.service: Scheduled restart job, restart counter is at 222.
This happens on the Hub every couple of hours.