[stunnel-users] stunnel 5.18 may keep high CPU usage

Mon Jun 15 22:38:52 CEST 2015

Hello Michal,

Same  problem with 5.19b4 and nothing special in the logs.

Now  I know how to reproduce the problem instantly, I just have to put
my computer in StanBy mode and Awake it.

Using  Process Explorer from Sysinternals I see that stunnel produce a
permanent "Other I/O" flow when problem appear.

I/O  Other  :  "The  rate at which the process is issuing bytes to I/O
operations  that  do not involve data such as control operations. This
counter  counts  all  I/O activity generated by the process to include
file, network and device I/Os."

OtherI/O  is  confirmed  by  Process  Monitor  that  trace no File nor
Registry nor Network activity.

But  as  stunnel  still  respond correctly to a Quit menu or any other
menus  and  SSL  requests  I  assumed that it may be some Thread going
crazy  so  I  compared  running thread between normal stunnel behavior
with  the  25%  CPU  behavior and found that in fact there is a thread
that do no terminate correctly.

Here is the Thread's stack :

MSVCR90.dll!_endThread+0x7d
ntoskrnl.exe!memset+0x61a
ntoskrnl.exe!KeWaitForMultipleObjects+0xd52
ntoskrnl.exe!KeWaitForSingleObject+0x19f
ntoskrnl.exe!PoStartNextPowerIrp+0xba4
ntoskrnl.exe!PoStartNextPowerIrp+0x1821
ntoskrnl.exe!PoStartNextPowerIrp+0x1a97
ntoskrnl.exe!KeReleaseInStackQueuedSpinLock+0x5a
afd.sys+0x61c1c
afd.sys+0x51d3b
ntoskrnl.exe!NtMapViewOfSection+0x15b7
ntoskrnl.exe!NtDeviceIoControlFile+0x56
ntoskrnl.exe!KeSynchronizeExecution+0x3a23
wow64cpu.dll!TurboDispatchJumpAddressEnd+0x6c0
wow64cpu.dll!TurboDispatchJumpAddressEnd+0x1fb
wow64.dll!Wow64SystemServiceEx+0x1ce
wow64.dll!Wow64LdrpInitialize+0x42a
ntdll.dll!RtlIsDosDeviceName_U+0x1f5c4
ntdll.dll!LdrInitializeThunk+0xe
ntdll.dll!NtDeviceIoControlFile+0x15
WS2_32.dll!select+0x9f
stunnel.exe!OPENSSL_Applink+0xd3ec
stunnel.exe!OPENSSL_Applink+0x961

Hope it help...

regards.

MT> Please try stunnel 5.19b4:
MT> https://www.stunnel.org/downloads.html