The node.js app is unable to process requests. Below is the dump of w3wp.exe threads. It appears iisnode is blocked waiting on critical sections which prevents processing of requests.

ntdll!NtWaitForKeyedEvent+15
ntdll!RtlAcquireSRWLockExclusive+12e
iisnode!CNodeApplicationManager::RecycleApplication+45 c:\projects\iisnode\src\iisnode\cnodeapplicationmanager.cpp @ 298 + a
iisnode!CNodeApplicationManager::OnScriptModified+11 c:\projects\iisnode\src\iisnode\cnodeapplicationmanager.cpp @ 336
iisnode!CFileWatcher::ScanDirectory+1c0 c:\projects\iisnode\src\iisnode\cfilewatcher.cpp @ 565 + 19
iisnode!CFileWatcher::Worker+bb c:\projects\iisnode\src\iisnode\cfilewatcher.cpp @ 504
msvcr100!_endthreadex+3f
msvcr100!_endthreadex+ce
kernel32!BaseThreadInitThunk+e
ntdll!__RtlUserThreadStart+70
ntdll!_RtlUserThreadStart+1b

We got other threads like below stuck wanting to get that critical section lock

ntdll!ZwWaitForSingleObject+15
ntdll!RtlpWaitOnCriticalSection+13e
ntdll!RtlEnterCriticalSection+150
iisnode!CFileWatcher::RemoveWatch+3f c:\projects\iisnode\src\iisnode\cfilewatcher.cpp @ 408 + a
iisnode!CNodeApplication::~CNodeApplication+13 c:\projects\iisnode\src\iisnode\cnodeapplication.cpp @ 11 + 10
iisnode!CNodeProcessManager::GracefulShutdown+e5 c:\projects\iisnode\src\iisnode\cnodeprocessmanager.cpp @ 343
msvcr100!_endthreadex+3f
msvcr100!_endthreadex+ce
kernel32!BaseThreadInitThunk+e
ntdll!__RtlUserThreadStart+70
ntdll!_RtlUserThreadStart+1b

ntdll!ZwWaitForSingleObject+15
ntdll!RtlpWaitOnCriticalSection+13e
ntdll!RtlEnterCriticalSection+150
iisnode!CFileWatcher::WatchFiles+33b c:\projects\iisnode\src\iisnode\cfilewatcher.cpp @ 139 + 10
iisnode!CNodeApplication::Initialize+fc c:\projects\iisnode\src\iisnode\cnodeapplication.cpp @ 49 + 26
iisnode!CNodeApplicationManager::GetOrCreateNodeApplicationCore+ad c:\projects\iisnode\src\iisnode\cnodeapplicationmanager.cpp @ 380 + c
iisnode!CNodeApplicationManager::GetOrCreateNodeApplication+98 c:\projects\iisnode\src\iisnode\cnodeapplicationmanager.cpp @ 653 + 11
iisnode!CNodeApplicationManager::Dispatch+111 c:\projects\iisnode\src\iisnode\cnodeapplicationmanager.cpp @ 205 + 12
iisnode!CNodeHttpModule::OnExecuteRequestHandler+97 c:\projects\iisnode\src\iisnode\cnodehttpmodule.cpp @ 26 + 11
iiscore!NOTIFICATION_CONTEXT::RequestDoWork+128
iiscore!NOTIFICATION_CONTEXT::CallModulesInternal+305
iiscore!NOTIFICATION_CONTEXT::CallModules+28
iiscore!W3_CONTEXT::DoStateRequestExecuteHandler+36
iiscore!W3_CONTEXT::DoWork+d7
iiscore!W3_MAIN_CONTEXT::StartNotificationLoop+49
iiscore!W3_CONTEXT::ExecuteRequest+20c
rewrite!RegisterModule+4fd4
rewrite!RegisterModule+817e
rewrite!RegisterModule+1c24f
rewrite!RegisterModule+3e65
rewrite!RegisterModule+5eb
iiscore!NOTIFICATION_CONTEXT::RequestDoWork+d5
iiscore!NOTIFICATION_CONTEXT::CallModulesInternal+305
iiscore!NOTIFICATION_CONTEXT::CallModules+28
iiscore!W3_CONTEXT::DoStateRequestStart+63
iiscore!W3_CONTEXT::DoWork+8d
iiscore!W3_MAIN_CONTEXT::StartNotificationLoop+49
iiscore!W3_MAIN_CONTEXT::OnNewRequest+47
w3dt!UL_NATIVE_REQUEST::DoStateProcess+26
w3dt!UL_NATIVE_REQUEST::DoWork+60
w3dt!OverlappedCompletionRoutine+1a
w3tp!THREAD_POOL_DATA::ThreadPoolThread+89
w3tp!THREAD_POOL_DATA::ThreadPoolThread+24
w3tp!THREAD_MANAGER::ThreadManagerThread+39
kernel32!BaseThreadInitThunk+e
ntdll!__RtlUserThreadStart+70
ntdll!_RtlUserThreadStart+1b

ntdll!NtWaitForKeyedEvent+15
ntdll!RtlAcquireSRWLockShared+105
iisnode!CNodeApplicationManager::Dispatch+96 c:\projects\iisnode\src\iisnode\cnodeapplicationmanager.cpp @ 186 + a
iisnode!CNodeHttpModule::OnExecuteRequestHandler+97 c:\projects\iisnode\src\iisnode\cnodehttpmodule.cpp @ 26 + 11
iiscore!NOTIFICATION_CONTEXT::RequestDoWork+128
iiscore!NOTIFICATION_CONTEXT::CallModulesInternal+305
iiscore!NOTIFICATION_CONTEXT::CallModules+28
iiscore!W3_CONTEXT::DoStateRequestExecuteHandler+36
iiscore!W3_CONTEXT::DoWork+d7
iiscore!W3_MAIN_CONTEXT::StartNotificationLoop+49
iiscore!W3_CONTEXT::ExecuteRequest+20c
rewrite!RegisterModule+4fd4
rewrite!RegisterModule+22aa9
rewrite!RegisterModule+1c3f2
rewrite!RegisterModule+3e65
rewrite!RegisterModule+5eb
iiscore!NOTIFICATION_CONTEXT::RequestDoWork+d5
iiscore!NOTIFICATION_CONTEXT::CallModulesInternal+305
iiscore!NOTIFICATION_CONTEXT::CallModules+28
iiscore!W3_CONTEXT::DoStateRequestStart+63
iiscore!W3_CONTEXT::DoWork+8d
iiscore!W3_MAIN_CONTEXT::StartNotificationLoop+49
iiscore!W3_MAIN_CONTEXT::OnNewRequest+47
w3dt!UL_NATIVE_REQUEST::DoStateProcess+26
w3dt!UL_NATIVE_REQUEST::DoWork+60
w3dt!OverlappedCompletionRoutine+1a
w3tp!THREAD_POOL_DATA::ThreadPoolThread+89
w3tp!THREAD_POOL_DATA::ThreadPoolThread+24
w3tp!THREAD_MANAGER::ThreadManagerThread+39
kernel32!BaseThreadInitThunk+e
ntdll!__RtlUserThreadStart+70
ntdll!_RtlUserThreadStart+1b