[PATCH 1/2] manpage: Add a description of the 'nconnect' mount option

[PATCH 1/2] manpage: Add a description of the 'nconnect' mount option

[Steve Dickson]

From: Trond Myklebust <trond.myklebust@hammerspace.com>

Add a description of the 'nconnect' mount option on the 'nfs' generic
manpage.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Steve Dickson <steved@redhat.com>
---
 utils/mount/nfs.man | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man
index 6ba9cef..84462cd 100644
--- a/utils/mount/nfs.man
+++ b/utils/mount/nfs.man
@@ -369,6 +369,23 @@ using an automounter (refer to
 .BR automount (8)
 for details).
 .TP 1.5i
+.BR nconnect= n
+When using a connection oriented protocol such as TCP, it may
+sometimes be advantageous to set up multiple connections between
+the client and server. For instance, if your clients and/or servers
+are equipped with multiple network interface cards (NICs), using multiple
+connections to spread the load may improve overall performance.
+In such cases, the
+.BR nconnect
+option allows the user to specify the number of connections
+that should be established between the client and server up to
+a limit of 16.
+.IP
+Note that the
+.BR nconnect
+option may also be used by some pNFS drivers to decide how many
+connections to set up to the data servers.
+.TP 1.5i
 .BR rdirplus " / " nordirplus
 Selects whether to use NFS v3 or v4 READDIRPLUS requests.
 If this option is not specified, the NFS client uses READDIRPLUS requests
-- 
2.21.1

[PATCH 2/2] manpage: Add a description of the 'softreval' / 'nosoftreval' mount option

[Steve Dickson]

From: Trond Myklebust <trond.myklebust@hammerspace.com>

Add a description of the 'softreval' / 'nosoftreval' mount options on
the 'nfs' generic manpage.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Steve Dickson <steved@redhat.com>
---
 utils/mount/nfs.man | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man
index 84462cd..6f79c63 100644
--- a/utils/mount/nfs.man
+++ b/utils/mount/nfs.man
@@ -121,6 +121,36 @@ option may mitigate some of the risks of using the
 .B soft
 option.
 .TP 1.5i
+.BR softreval " / " nosoftreval
+In cases where the NFS server is down, it may be useful to
+allow the NFS client to continue to serve up paths and
+attributes from cache after
+.B retrans
+attempts to revalidate that cache have timed out.
+This may, for instance, be helpful when trying to unmount a
+filesystem tree from a server that is permanently down.
+.IP
+It is possible to combine
+.BR softreval
+with the
+.B soft
+mount option, in which case operations that cannot be served up
+from cache will time out and return an error after
+.B retrans
+attempts. The combination with the default
+.B hard
+mount option implies those uncached operations will continue to
+retry until a response is received from the server.
+.IP
+Note: the default mount option is
+.BR nosoftreval
+which disallows fallback to cache when revalidation fails, and
+instead follows the behavior dictated by the
+.B hard
+or
+.B soft
+mount option.
+.TP 1.5i
 .BR intr " / " nointr
 This option is provided for backward compatibility.
 It is ignored after kernel 2.6.25.
-- 
2.21.1

Re: [PATCH 1/2] manpage: Add a description of the 'nconnect' mount option

[Olga Kornievskaia]

Looks good but can we add clarification that nconnect is supported for
3.0 and 4.1+?

On Wed, Jan 29, 2020 at 10:47 AM Steve Dickson <steved@redhat.com> wrote:
>
> From: Trond Myklebust <trond.myklebust@hammerspace.com>
>
> Add a description of the 'nconnect' mount option on the 'nfs' generic
> manpage.
>
> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
> Signed-off-by: Steve Dickson <steved@redhat.com>
> ---
>  utils/mount/nfs.man | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
>
> diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man
> index 6ba9cef..84462cd 100644
> --- a/utils/mount/nfs.man
> +++ b/utils/mount/nfs.man
> @@ -369,6 +369,23 @@ using an automounter (refer to
>  .BR automount (8)
>  for details).
>  .TP 1.5i
> +.BR nconnect= n
> +When using a connection oriented protocol such as TCP, it may
> +sometimes be advantageous to set up multiple connections between
> +the client and server. For instance, if your clients and/or servers
> +are equipped with multiple network interface cards (NICs), using multiple
> +connections to spread the load may improve overall performance.
> +In such cases, the
> +.BR nconnect
> +option allows the user to specify the number of connections
> +that should be established between the client and server up to
> +a limit of 16.
> +.IP
> +Note that the
> +.BR nconnect
> +option may also be used by some pNFS drivers to decide how many
> +connections to set up to the data servers.
> +.TP 1.5i
>  .BR rdirplus " / " nordirplus
>  Selects whether to use NFS v3 or v4 READDIRPLUS requests.
>  If this option is not specified, the NFS client uses READDIRPLUS requests
> --
> 2.21.1
>

Re: [PATCH 1/2] manpage: Add a description of the 'nconnect' mount option

[Steve Dickson]

Trond,

On 2/3/20 10:15 AM, Olga Kornievskaia wrote:
> Looks good but can we add clarification that nconnect is supported for
> 3.0 and 4.1+?
Do you have an opinion on this? Should we document the protocols that
are supported?

steved.

> 
> On Wed, Jan 29, 2020 at 10:47 AM Steve Dickson <steved@redhat.com> wrote:
>>
>> From: Trond Myklebust <trond.myklebust@hammerspace.com>
>>
>> Add a description of the 'nconnect' mount option on the 'nfs' generic
>> manpage.
>>
>> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
>> Signed-off-by: Steve Dickson <steved@redhat.com>
>> ---
>>  utils/mount/nfs.man | 17 +++++++++++++++++
>>  1 file changed, 17 insertions(+)
>>
>> diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man
>> index 6ba9cef..84462cd 100644
>> --- a/utils/mount/nfs.man
>> +++ b/utils/mount/nfs.man
>> @@ -369,6 +369,23 @@ using an automounter (refer to
>>  .BR automount (8)
>>  for details).
>>  .TP 1.5i
>> +.BR nconnect= n
>> +When using a connection oriented protocol such as TCP, it may
>> +sometimes be advantageous to set up multiple connections between
>> +the client and server. For instance, if your clients and/or servers
>> +are equipped with multiple network interface cards (NICs), using multiple
>> +connections to spread the load may improve overall performance.
>> +In such cases, the
>> +.BR nconnect
>> +option allows the user to specify the number of connections
>> +that should be established between the client and server up to
>> +a limit of 16.
>> +.IP
>> +Note that the
>> +.BR nconnect
>> +option may also be used by some pNFS drivers to decide how many
>> +connections to set up to the data servers.
>> +.TP 1.5i
>>  .BR rdirplus " / " nordirplus
>>  Selects whether to use NFS v3 or v4 READDIRPLUS requests.
>>  If this option is not specified, the NFS client uses READDIRPLUS requests
>> --
>> 2.21.1
>>
> 

Re: [PATCH 1/2] manpage: Add a description of the 'nconnect' mount option

[Trond Myklebust]

On Tue, 2020-02-04 at 11:46 -0500, Steve Dickson wrote:
> Trond,
> 
> On 2/3/20 10:15 AM, Olga Kornievskaia wrote:
> > Looks good but can we add clarification that nconnect is supported
> > for
> > 3.0 and 4.1+?
> Do you have an opinion on this? Should we document the protocols that
> are supported?

Unless there is an actual protocol reason for doing so, I'd rather not
that we be on the record as saying that NFSv4.0 will remain
unsupported.
In other words, I'd like us to keep open the possibility that we might
add NFSv4.0 support in the future, should someone need it.

Cheers
  Trond


> steved.
> 
> > On Wed, Jan 29, 2020 at 10:47 AM Steve Dickson <steved@redhat.com>
> > wrote:
> > > From: Trond Myklebust <trond.myklebust@hammerspace.com>
> > > 
> > > Add a description of the 'nconnect' mount option on the 'nfs'
> > > generic
> > > manpage.
> > > 
> > > Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
> > > Signed-off-by: Steve Dickson <steved@redhat.com>
> > > ---
> > >  utils/mount/nfs.man | 17 +++++++++++++++++
> > >  1 file changed, 17 insertions(+)
> > > 
> > > diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man
> > > index 6ba9cef..84462cd 100644
> > > --- a/utils/mount/nfs.man
> > > +++ b/utils/mount/nfs.man
> > > @@ -369,6 +369,23 @@ using an automounter (refer to
> > >  .BR automount (8)
> > >  for details).
> > >  .TP 1.5i
> > > +.BR nconnect= n
> > > +When using a connection oriented protocol such as TCP, it may
> > > +sometimes be advantageous to set up multiple connections between
> > > +the client and server. For instance, if your clients and/or
> > > servers
> > > +are equipped with multiple network interface cards (NICs), using
> > > multiple
> > > +connections to spread the load may improve overall performance.
> > > +In such cases, the
> > > +.BR nconnect
> > > +option allows the user to specify the number of connections
> > > +that should be established between the client and server up to
> > > +a limit of 16.
> > > +.IP
> > > +Note that the
> > > +.BR nconnect
> > > +option may also be used by some pNFS drivers to decide how many
> > > +connections to set up to the data servers.
> > > +.TP 1.5i
> > >  .BR rdirplus " / " nordirplus
> > >  Selects whether to use NFS v3 or v4 READDIRPLUS requests.
> > >  If this option is not specified, the NFS client uses READDIRPLUS
> > > requests
> > > --
> > > 2.21.1
> > > 
-- 
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@hammerspace.com

Re: [PATCH 1/2] manpage: Add a description of the 'nconnect' mount option

[Olga Kornievskaia]

On Tue, Feb 4, 2020 at 12:13 PM Trond Myklebust <trondmy@hammerspace.com> wrote:
>
> On Tue, 2020-02-04 at 11:46 -0500, Steve Dickson wrote:
> > Trond,
> >
> > On 2/3/20 10:15 AM, Olga Kornievskaia wrote:
> > > Looks good but can we add clarification that nconnect is supported
> > > for
> > > 3.0 and 4.1+?
> > Do you have an opinion on this? Should we document the protocols that
> > are supported?
>
> Unless there is an actual protocol reason for doing so, I'd rather not
> that we be on the record as saying that NFSv4.0 will remain
> unsupported.
> In other words, I'd like us to keep open the possibility that we might
> add NFSv4.0 support in the future, should someone need it.

I see your point and I like the vagueness of the nconnect description
but is the man page written in stone, can't we say that now support is
for v3 and v4.1+ but in the future it might change? It might be
confusing for the users to do a 4.0 mount, specify nconnect and wonder
why it's not working?

>
> Cheers
>   Trond
>
>
> > steved.
> >
> > > On Wed, Jan 29, 2020 at 10:47 AM Steve Dickson <steved@redhat.com>
> > > wrote:
> > > > From: Trond Myklebust <trond.myklebust@hammerspace.com>
> > > >
> > > > Add a description of the 'nconnect' mount option on the 'nfs'
> > > > generic
> > > > manpage.
> > > >
> > > > Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
> > > > Signed-off-by: Steve Dickson <steved@redhat.com>
> > > > ---
> > > >  utils/mount/nfs.man | 17 +++++++++++++++++
> > > >  1 file changed, 17 insertions(+)
> > > >
> > > > diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man
> > > > index 6ba9cef..84462cd 100644
> > > > --- a/utils/mount/nfs.man
> > > > +++ b/utils/mount/nfs.man
> > > > @@ -369,6 +369,23 @@ using an automounter (refer to
> > > >  .BR automount (8)
> > > >  for details).
> > > >  .TP 1.5i
> > > > +.BR nconnect= n
> > > > +When using a connection oriented protocol such as TCP, it may
> > > > +sometimes be advantageous to set up multiple connections between
> > > > +the client and server. For instance, if your clients and/or
> > > > servers
> > > > +are equipped with multiple network interface cards (NICs), using
> > > > multiple
> > > > +connections to spread the load may improve overall performance.
> > > > +In such cases, the
> > > > +.BR nconnect
> > > > +option allows the user to specify the number of connections
> > > > +that should be established between the client and server up to
> > > > +a limit of 16.
> > > > +.IP
> > > > +Note that the
> > > > +.BR nconnect
> > > > +option may also be used by some pNFS drivers to decide how many
> > > > +connections to set up to the data servers.
> > > > +.TP 1.5i
> > > >  .BR rdirplus " / " nordirplus
> > > >  Selects whether to use NFS v3 or v4 READDIRPLUS requests.
> > > >  If this option is not specified, the NFS client uses READDIRPLUS
> > > > requests
> > > > --
> > > > 2.21.1
> > > >
> --
> Trond Myklebust
> Linux NFS client maintainer, Hammerspace
> trond.myklebust@hammerspace.com
>
>

Re: [PATCH 1/2] manpage: Add a description of the 'nconnect' mount option

[Trond Myklebust]

On Tue, 2020-02-04 at 12:22 -0500, Olga Kornievskaia wrote:
> On Tue, Feb 4, 2020 at 12:13 PM Trond Myklebust <
> trondmy@hammerspace.com> wrote:
> > On Tue, 2020-02-04 at 11:46 -0500, Steve Dickson wrote:
> > > Trond,
> > > 
> > > On 2/3/20 10:15 AM, Olga Kornievskaia wrote:
> > > > Looks good but can we add clarification that nconnect is
> > > > supported
> > > > for
> > > > 3.0 and 4.1+?
> > > Do you have an opinion on this? Should we document the protocols
> > > that
> > > are supported?
> > 
> > Unless there is an actual protocol reason for doing so, I'd rather
> > not
> > that we be on the record as saying that NFSv4.0 will remain
> > unsupported.
> > In other words, I'd like us to keep open the possibility that we
> > might
> > add NFSv4.0 support in the future, should someone need it.
> 
> I see your point and I like the vagueness of the nconnect description
> but is the man page written in stone, can't we say that now support
> is
> for v3 and v4.1+ but in the future it might change? It might be
> confusing for the users to do a 4.0 mount, specify nconnect and
> wonder
> why it's not working?

Well... Given that it is really a bug (i.e. not intentional) that
NFSv4.0 does not work, I'd argue those users should be allowed the
option to complain.

> 
> > Cheers
> >   Trond
> > 
> > 
> > > steved.
> > > 
> > > > On Wed, Jan 29, 2020 at 10:47 AM Steve Dickson <
> > > > steved@redhat.com>
> > > > wrote:
> > > > > From: Trond Myklebust <trond.myklebust@hammerspace.com>
> > > > > 
> > > > > Add a description of the 'nconnect' mount option on the 'nfs'
> > > > > generic
> > > > > manpage.
> > > > > 
> > > > > Signed-off-by: Trond Myklebust <
> > > > > trond.myklebust@hammerspace.com>
> > > > > Signed-off-by: Steve Dickson <steved@redhat.com>
> > > > > ---
> > > > >  utils/mount/nfs.man | 17 +++++++++++++++++
> > > > >  1 file changed, 17 insertions(+)
> > > > > 
> > > > > diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man
> > > > > index 6ba9cef..84462cd 100644
> > > > > --- a/utils/mount/nfs.man
> > > > > +++ b/utils/mount/nfs.man
> > > > > @@ -369,6 +369,23 @@ using an automounter (refer to
> > > > >  .BR automount (8)
> > > > >  for details).
> > > > >  .TP 1.5i
> > > > > +.BR nconnect= n
> > > > > +When using a connection oriented protocol such as TCP, it
> > > > > may
> > > > > +sometimes be advantageous to set up multiple connections
> > > > > between
> > > > > +the client and server. For instance, if your clients and/or
> > > > > servers
> > > > > +are equipped with multiple network interface cards (NICs),
> > > > > using
> > > > > multiple
> > > > > +connections to spread the load may improve overall
> > > > > performance.
> > > > > +In such cases, the
> > > > > +.BR nconnect
> > > > > +option allows the user to specify the number of connections
> > > > > +that should be established between the client and server up
> > > > > to
> > > > > +a limit of 16.
> > > > > +.IP
> > > > > +Note that the
> > > > > +.BR nconnect
> > > > > +option may also be used by some pNFS drivers to decide how
> > > > > many
> > > > > +connections to set up to the data servers.
> > > > > +.TP 1.5i
> > > > >  .BR rdirplus " / " nordirplus
> > > > >  Selects whether to use NFS v3 or v4 READDIRPLUS requests.
> > > > >  If this option is not specified, the NFS client uses
> > > > > READDIRPLUS
> > > > > requests
> > > > > --
> > > > > 2.21.1
> > > > > 
> > 
-- 
Trond Myklebust
Linux NFS client maintainer, Hammerspace
trond.myklebust@hammerspace.com

Re: [PATCH 2/2] manpage: Add a description of the 'softreval' / 'nosoftreval' mount option

[Steve Dickson]

On 1/29/20 10:47 AM, Steve Dickson wrote:
> From: Trond Myklebust <trond.myklebust@hammerspace.com>
> 
> Add a description of the 'softreval' / 'nosoftreval' mount options on
> the 'nfs' generic manpage.
> 
> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
> Signed-off-by: Steve Dickson <steved@redhat.com>
Committed... (tag: nfs-utils-2-4-3-rc7)

steved.

> ---
>  utils/mount/nfs.man | 30 ++++++++++++++++++++++++++++++
>  1 file changed, 30 insertions(+)
> 
> diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man
> index 84462cd..6f79c63 100644
> --- a/utils/mount/nfs.man
> +++ b/utils/mount/nfs.man
> @@ -121,6 +121,36 @@ option may mitigate some of the risks of using the
>  .B soft
>  option.
>  .TP 1.5i
> +.BR softreval " / " nosoftreval
> +In cases where the NFS server is down, it may be useful to
> +allow the NFS client to continue to serve up paths and
> +attributes from cache after
> +.B retrans
> +attempts to revalidate that cache have timed out.
> +This may, for instance, be helpful when trying to unmount a
> +filesystem tree from a server that is permanently down.
> +.IP
> +It is possible to combine
> +.BR softreval
> +with the
> +.B soft
> +mount option, in which case operations that cannot be served up
> +from cache will time out and return an error after
> +.B retrans
> +attempts. The combination with the default
> +.B hard
> +mount option implies those uncached operations will continue to
> +retry until a response is received from the server.
> +.IP
> +Note: the default mount option is
> +.BR nosoftreval
> +which disallows fallback to cache when revalidation fails, and
> +instead follows the behavior dictated by the
> +.B hard
> +or
> +.B soft
> +mount option.
> +.TP 1.5i
>  .BR intr " / " nointr
>  This option is provided for backward compatibility.
>  It is ignored after kernel 2.6.25.
> 

Re: [PATCH 1/2] manpage: Add a description of the 'nconnect' mount option

[Steve Dickson]

On 1/29/20 10:47 AM, Steve Dickson wrote:
> From: Trond Myklebust <trond.myklebust@hammerspace.com>
> 
> Add a description of the 'nconnect' mount option on the 'nfs' generic
> manpage.
> 
> Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
> Signed-off-by: Steve Dickson <steved@redhat.com>
Committed... (tag: nfs-utils-2-4-3-rc7)

steved.
> ---
>  utils/mount/nfs.man | 17 +++++++++++++++++
>  1 file changed, 17 insertions(+)
> 
> diff --git a/utils/mount/nfs.man b/utils/mount/nfs.man
> index 6ba9cef..84462cd 100644
> --- a/utils/mount/nfs.man
> +++ b/utils/mount/nfs.man
> @@ -369,6 +369,23 @@ using an automounter (refer to
>  .BR automount (8)
>  for details).
>  .TP 1.5i
> +.BR nconnect= n
> +When using a connection oriented protocol such as TCP, it may
> +sometimes be advantageous to set up multiple connections between
> +the client and server. For instance, if your clients and/or servers
> +are equipped with multiple network interface cards (NICs), using multiple
> +connections to spread the load may improve overall performance.
> +In such cases, the
> +.BR nconnect
> +option allows the user to specify the number of connections
> +that should be established between the client and server up to
> +a limit of 16.
> +.IP
> +Note that the
> +.BR nconnect
> +option may also be used by some pNFS drivers to decide how many
> +connections to set up to the data servers.
> +.TP 1.5i
>  .BR rdirplus " / " nordirplus
>  Selects whether to use NFS v3 or v4 READDIRPLUS requests.
>  If this option is not specified, the NFS client uses READDIRPLUS requests
>