2011-04-26 14:05:25

by Mkrtchyan, Tigran

[permalink] [raw]
Subject: pNFS read/write behavior change in 2.6.39


I run 2.6.39-0.rc4.git2.0 build for fedora-16 build by redhat.
Probably Steve and Bruce can comment on the patch set.

My observation is that state id provided by client on read to
DS dit not contain correct stateid:

struct stateid4 {
uint32_t seqid;
opaque other[12];
};

The seqid equals to zero when client send it to DS which is not the
value returned on OPEN.

The problem is not observed with

ae7441fa120ff35b40b4dab167645907a9da1dab

from Bennys tree as well as with frdora 15 builds from Steve.
With
Regards,
Tigran.


2011-04-26 16:52:24

by Myklebust, Trond

[permalink] [raw]
Subject: Re: pNFS read/write behavior change in 2.6.39

On Tue, 2011-04-26 at 16:37 +0200, Tigran Mkrtchyan wrote:
> On 04/26/2011 04:29 PM, Trond Myklebust wrote:
> > On Tue, 2011-04-26 at 16:03 +0200, Tigran Mkrtchyan wrote:
> >> I run 2.6.39-0.rc4.git2.0 build for fedora-16 build by redhat.
> >> Probably Steve and Bruce can comment on the patch set.
> >>
> >> My observation is that state id provided by client on read to
> >> DS dit not contain correct stateid:
> >>
> >> struct stateid4 {
> >> uint32_t seqid;
> >> opaque other[12];
> >> };
> >>
> >> The seqid equals to zero when client send it to DS which is not the
> >> value returned on OPEN.
> > Why do you think this is a bug? Section 8.2.2 of RFC5661 not only allows
> > this behaviour, it actually suggests it is appropriate for READ and
> > WRITE since it means that the server isn't forced to constantly check
> > the seqid value.
> Well, It's not a bug, but it's not the behavior we was testing at
> Connectathon.
> My expectation was that during interoperability testing we catch such
> changes.

My expectation is that everyone is coding to the spec, and not to
specific client or server behaviours. The main goal of interoperability
testing should be to discover deviations from the spec and/or incomplete
implementations.

Cheers
Trond

--
Trond Myklebust
Linux NFS client maintainer

NetApp
[email protected]
http://www.netapp.com


2011-04-26 14:41:36

by Mkrtchyan, Tigran

[permalink] [raw]
Subject: Re: pNFS read/write behavior change in 2.6.39

On 04/26/2011 04:37 PM, Tigran Mkrtchyan wrote:
> On 04/26/2011 04:29 PM, Trond Myklebust wrote:
>> On Tue, 2011-04-26 at 16:03 +0200, Tigran Mkrtchyan wrote:
>>> I run 2.6.39-0.rc4.git2.0 build for fedora-16 build by redhat.
>>> Probably Steve and Bruce can comment on the patch set.
>>>
>>> My observation is that state id provided by client on read to
>>> DS dit not contain correct stateid:
>>>
>>> struct stateid4 {
>>> uint32_t seqid;
>>> opaque other[12];
>>> };
>>>
>>> The seqid equals to zero when client send it to DS which is not the
>>> value returned on OPEN.
>> Why do you think this is a bug? Section 8.2.2 of RFC5661 not only allows
>> this behaviour, it actually suggests it is appropriate for READ and
>> WRITE since it means that the server isn't forced to constantly check
>> the seqid value.
> Well, It's not a bug, but it's not the behavior we was testing at
> Connectathon.
> My expectation was that during interoperability testing we catch such
> changes.

Nevertheless, that can be failure on my side as I have a different DS
at Connectathon and
in the production.
>
> Tigran.
>> Trond
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
> the body of a message to [email protected]
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2011-04-26 14:29:56

by Myklebust, Trond

[permalink] [raw]
Subject: Re: pNFS read/write behavior change in 2.6.39

On Tue, 2011-04-26 at 16:03 +0200, Tigran Mkrtchyan wrote:
> I run 2.6.39-0.rc4.git2.0 build for fedora-16 build by redhat.
> Probably Steve and Bruce can comment on the patch set.
>
> My observation is that state id provided by client on read to
> DS dit not contain correct stateid:
>
> struct stateid4 {
> uint32_t seqid;
> opaque other[12];
> };
>
> The seqid equals to zero when client send it to DS which is not the
> value returned on OPEN.

Why do you think this is a bug? Section 8.2.2 of RFC5661 not only allows
this behaviour, it actually suggests it is appropriate for READ and
WRITE since it means that the server isn't forced to constantly check
the seqid value.

Trond
--
Trond Myklebust
Linux NFS client maintainer

NetApp
[email protected]
http://www.netapp.com


2011-04-26 14:39:23

by Mkrtchyan, Tigran

[permalink] [raw]
Subject: Re: pNFS read/write behavior change in 2.6.39

On 04/26/2011 04:29 PM, Trond Myklebust wrote:
> On Tue, 2011-04-26 at 16:03 +0200, Tigran Mkrtchyan wrote:
>> I run 2.6.39-0.rc4.git2.0 build for fedora-16 build by redhat.
>> Probably Steve and Bruce can comment on the patch set.
>>
>> My observation is that state id provided by client on read to
>> DS dit not contain correct stateid:
>>
>> struct stateid4 {
>> uint32_t seqid;
>> opaque other[12];
>> };
>>
>> The seqid equals to zero when client send it to DS which is not the
>> value returned on OPEN.
> Why do you think this is a bug? Section 8.2.2 of RFC5661 not only allows
> this behaviour, it actually suggests it is appropriate for READ and
> WRITE since it means that the server isn't forced to constantly check
> the seqid value.
Well, It's not a bug, but it's not the behavior we was testing at
Connectathon.
My expectation was that during interoperability testing we catch such
changes.

Tigran.
> Trond