Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 3 Dec 2019 18:03:00 +0100
From:      Peter Eriksson <pen@lysator.liu.se>
To:        FreeBSD FS <freebsd-fs@freebsd.org>
Cc:        Andriy Gapon <avg@FreeBSD.org>, Bengt Ahlgren <bengt.ahlgren@ri.se>
Subject:   Re: Slow reboots due to ZFS cleanup in kern_shutdown() .. zio_fini()
Message-ID:  <DD98024A-4DA5-45C1-953E-0C515A9F7DFB@lysator.liu.se>
In-Reply-To: <uh75zixfiqw.fsf@P142.sics.se>
References:  <AD17E454-6A51-436D-A853-07F04A406EC9@lysator.liu.se> <D2A11CE9-9B24-4E40-A51A-8D318E0288C9@lysator.liu.se> <20191202225424.GG43802@raichu> <3b71fe37-c29f-e3e5-ff96-5dce15cc7553@FreeBSD.org> <DAD21732-AB7C-4B8D-99BF-25C7DD238A31@lysator.liu.se> <uh75zixfiqw.fsf@P142.sics.se>

next in thread | previous in thread | raw e-mail | index | archive | help
We run without swap on our servers=E2=80=A6

I=E2=80=99m trying to instrument the uma_zdestroy() code now, should =
provide some more details in an hour or two=E2=80=A6 :-)

- Peter


> On 3 Dec 2019, at 17:59, Bengt Ahlgren <bengt.ahlgren@ri.se> wrote:
>=20
> Peter Eriksson <pen@lysator.liu.se <mailto:pen@lysator.liu.se>> =
writes:
>=20
>>>> uma_destroy() frees all of the memory cached in the zone back to =
the
>>>> page allocator.  This operation takes time proportional to the =
number of
>>>> cached items.  I would expect most of the time to be spent in
>>>> zone_reclaim(), called by zone_dtor().
>>>=20
>>> But spending *minutes* there is really unexpected.
>>> I have never seen anything like that.
>>> I wonder if there is anything untypical about the system's hardware
>>> (like a very
>>> big number of processors) or configuration.
>>>=20
>>> --=20
>>> Andriy Gapon
>>=20
>> It=E2=80=99s a fairly standard Dell PowerEdge R730xd server with =
Intel Xeon
>> E5-2620v4 CPUs & 256GB of RAM=E2=80=A6 (and an LSI SAS3 HBA and Intel =
10GE
>> ethernet)
>>=20
>> CPU: Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz (2100.04-MHz K8-class =
CPU)
>>  Origin=3D"GenuineIntel"  Id=3D0x406f1  Family=3D0x6  Model=3D0x4f  =
Stepping=3D1
>>  =
Features=3D0xbfebfbff<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=3D0x7ffefbff<SSE3,PCLMULQDQ,DTES64,MON,DS_CPL,VMX,SMX,EST,TM2,SS=
SE3,SDBG,FMA,CX16,xTPR,PDCM,PCID,DCA,SSE4.1,SSE4.2,x2APIC,MOVBE,POPCNT,TSC=
DLT,AESNI,XSAVE,OSXSAVE,AVX,F16C,RDRAND>
>>  AMD Features=3D0x2c100800<SYSCALL,NX,Page1GB,RDTSCP,LM>
>>  AMD Features2=3D0x121<LAHF,ABM,Prefetch>
>>  Structured Extended
>> =
Features=3D0x21cbfbb<FSGSBASE,TSCADJ,BMI1,HLE,AVX2,SMEP,BMI2,ERMS,INVPCID,=
RTM,PQM,NFPUSG,PQE,RDSEED,ADX,SMAP,PROCTRACE>
>>  Structured Extended =
Features3=3D0x9c000400<MD_CLEAR,IBPB,STIBP,L1DFL,SSBD>
>>  XSAVE Features=3D0x1<XSAVEOPT>
>>  VT-x: PAT,HLT,MTF,PAUSE,EPT,UG,VPID,VID,PostIntr
>>  TSC: P-state invariant, performance statistics
>> real memory  =3D 274869518336 (262136 MB)
>> avail memory =3D 267244859392 (254864 MB)
>> Event timer "LAPIC" quality 600
>> ACPI APIC Table: <DELL   PE_SC3  >
>> FreeBSD/SMP: Multiprocessor System Detected: 32 CPUs
>> FreeBSD/SMP: 2 package(s) x 8 core(s) x 2 hardware threads
>>=20
>> - Peter
>=20
> I also have a Dell server, but older (R515, 128GB RAM, AMD 2x8 cores,
> ~140TB disk, ARC cap 64GB) that has experienced the same behaviour.  I
> get the impression the shutdown time is related to used swap, but I =
have
> not investigated further.  I think the system disk (with swap -
> mechanical!) activity light is on during this time.  Now running =
11.3-R,
> but I'm sure I saw this with late 10.x as well.
>=20
> Bengt




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?DD98024A-4DA5-45C1-953E-0C515A9F7DFB>