Re: Complete hang on 9.0-RELEASE

Hi,

On Sat, Apr 21, 2012 at 4:19 AM, Arnaud Lacombe <lacombar_at_gmail.com> wrote:
> Hi,
>
> On Wed, Apr 18, 2012 at 2:22 AM, Arnaud Lacombe <lacombar_at_gmail.com> wrote:
>> Hi,
>>
>> On Mon, Apr 16, 2012 at 5:50 PM, Arnaud Lacombe <lacombar_at_gmail.com> wrote:
>>> [...]
>>> I reproduced the previous problem on 10-CURRENT from r233917, on the
>>> following platform (here running 8.2-RELEASE):
>>>
>>> FreeBSD is a registered trademark of The FreeBSD Foundation.
>>> FreeBSD 8.2-RELEASE #0: Thu Feb 17 02:41:51 UTC 2011
>>>    root_at_mason.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC amd64
>>> Timecounter "i8254" frequency 1193182 Hz quality 0
>>> CPU: Intel(R) Atom(TM) CPU D525   _at_ 1.80GHz (1800.01-MHz K8-class CPU)
>>>  Origin = "GenuineIntel"  Id = 0x106ca  Family = 6  Model = 1c  Stepping = 10
>>>  Features=0xbfebfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,DTS,ACPI,MMX,FXSR,SSE,SSE2,SS,HTT,TM,PBE>
>>>  Features2=0x40e31d<SSE3,DTES64,MON,DS_CPL,TM2,SSSE3,CX16,xTPR,PDCM,MOVBE>
>>>  AMD Features=0x20100800<SYSCALL,NX,LM>
>>>  AMD Features2=0x1<LAHF>
>>>  TSC: P-state invariant
>>> real memory  = 2136539136 (2037 MB)
>>> avail memory = 2043772928 (1949 MB)
>>> ACPI APIC Table: <010312 APIC0947>
>>> FreeBSD/SMP: Multiprocessor System Detected: 4 CPUs
>>> FreeBSD/SMP: 1 package(s) x 2 core(s) x 2 HTT threads
>>>  cpu0 (BSP): APIC ID:  0
>>>  cpu1 (AP/HT): APIC ID:  1
>>>  cpu2 (AP): APIC ID:  2
>>>  cpu3 (AP/HT): APIC ID:  3
>>>
>>> Complete system freeze while running about 2400 threads. I had to
>>> power cycle the system to get it back alive. I discussed a way to
>>> debug this with attilio_at_ on freebsd-stable_at_, but still did not had
>>> time to implement it.
>>>
>> 10-CURRENT from r233917 hanged again today while running 3600 threads.
>> I enabled WITNESS and INVARIANTS on that specific kernel, secretly
>> hoping that they would trigger some meaningful information, but they
>> did not. I would guess my last attempt is to enable SW_WATCHDOG, and
>> gather some state information out of DDB when the watchdog trigger, if
>> it does...
>>
>> Btw, this issue seems to be specifically happening on Atom/ICH8M
>> platform running amd64 kernel, as I've never seen it on other
>> platforms, and yet ran extensive tests. I am not entirely sure it
>> happens on i386. I would need to check.
>>
> For the record, 9.0-RELEASE i386 has been running the test for about 2
> days on the D510 platform without any hang so far. I'll keep it
> running all week-end to give me a better idea.
>
... or I have been too eager to expect an amd64 only issue. Thanks to
some nasty virus which stuck me in my bed for two days, I finally got
FreeBSD 9.0-RELEASE i386 stuck while running a single, 4000 threads,
process. I guess it's time to play with SW_WATCHDOG and DDB.

As a side note, the D510 platform seem to be much harder to hang than
the D525...

 - Arnaud