mtab and procs not in sync?

mtab and procs not in sync?

[Phy Prabab]

Hello,

Have run into a situation where mtab does not match
/proc/mounts in that mtab has numerous entries that
have expired off and removed, yet does not show that
it has been removed from mtab.  Is this known and is
there a fix?

Kernel 2.4.21 and 23
nfs-utils 1.06
automount 4.1.2

Thanks!
Phy


	
		
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RE: mtab and procs not in sync?

[Lever, Charles]

if there are a lot of mounts on the system, then /proc/mounts can be
truncated and not show all of them.

however, if there are more mounts in /proc/mounts than in /etc/mtab,
there is probably a bug in mount.  not unheard of.

> -----Original Message-----
> From: Phy Prabab [mailto:phyprabab@yahoo.com]=20
> Sent: Tuesday, June 08, 2004 2:21 PM
> To: nfs@lists.sourceforge.net
> Subject: [NFS] mtab and procs not in sync?
>=20
>=20
> Hello,
>=20
> Have run into a situation where mtab does not match
> /proc/mounts in that mtab has numerous entries that
> have expired off and removed, yet does not show that
> it has been removed from mtab.  Is this known and is
> there a fix?
>=20
> Kernel 2.4.21 and 23
> nfs-utils 1.06
> automount 4.1.2
>=20
> Thanks!
> Phy
>=20
>=20
> =09
> 	=09
> __________________________________
> Do you Yahoo!?
> Friends.  Fun.  Try the all-new Yahoo! Messenger.
> http://messenger.yahoo.com/=20
>=20
>=20
> -------------------------------------------------------
> This SF.Net email is sponsored by: GNOME Foundation
> Hackers Unite!  GUADEC: The world's #1 Open Source Desktop Event.
> GNOME Users and Developers European Conference, 28-30th June in Norway
> http://2004/guadec.org
> _______________________________________________
> NFS maillist  -  NFS@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/nfs
>=20


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RE: mtab and procs not in sync?

[Phy Prabab]

okay, how about many more mounts in mtab but not in
proc/mounts?  cat of proc/mounts shows 10 mount
points, mtab show 23.  I am guessing a bug? 

Thank you for your time.
Phy

--- "Lever, Charles" <Charles.Lever@netapp.com> wrote:
> if there are a lot of mounts on the system, then
> /proc/mounts can be
> truncated and not show all of them.
> 
> however, if there are more mounts in /proc/mounts
> than in /etc/mtab,
> there is probably a bug in mount.  not unheard of.
> 
> > -----Original Message-----
> > From: Phy Prabab [mailto:phyprabab@yahoo.com] 
> > Sent: Tuesday, June 08, 2004 2:21 PM
> > To: nfs@lists.sourceforge.net
> > Subject: [NFS] mtab and procs not in sync?
> > 
> > 
> > Hello,
> > 
> > Have run into a situation where mtab does not
> match
> > /proc/mounts in that mtab has numerous entries
> that
> > have expired off and removed, yet does not show
> that
> > it has been removed from mtab.  Is this known and
> is
> > there a fix?
> > 
> > Kernel 2.4.21 and 23
> > nfs-utils 1.06
> > automount 4.1.2
> > 
> > Thanks!
> > Phy
> > 
> > 
> > 	
> > 		
> > __________________________________
> > Do you Yahoo!?
> > Friends.  Fun.  Try the all-new Yahoo! Messenger.
> > http://messenger.yahoo.com/ 
> > 
> > 
> >
>
-------------------------------------------------------
> > This SF.Net email is sponsored by: GNOME
> Foundation
> > Hackers Unite!  GUADEC: The world's #1 Open Source
> Desktop Event.
> > GNOME Users and Developers European Conference,
> 28-30th June in Norway
> > http://2004/guadec.org
> > _______________________________________________
> > NFS maillist  -  NFS@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/nfs
> > 


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Re: mtab and procs not in sync?

[Ian Kent]

On Tue, 8 Jun 2004, Phy Prabab wrote:

> Hello,
> 
> Have run into a situation where mtab does not match
> /proc/mounts in that mtab has numerous entries that
> have expired off and removed, yet does not show that
> it has been removed from mtab.  Is this known and is
> there a fix?

This is not an NFS, kernel or automount issue.

The locking in mount appears to be broken. It usually shows up with autofs 
because it put quite a bit of pressure on mount.

But what is your environment?
I need more info. to understand this.
What 4.1.2 patches, if any, have you applied?

> 
> Kernel 2.4.21 and 23
> nfs-utils 1.06
> automount 4.1.2

I've tried to work around this problem and I discovered a coding error 
with that work the other day. I have a patch available at 

http://www.kernel.org/pub/linux/daemons/autofs/v4

called 

autofs-4.1.3-mtab_lock.patch

It is against 4.1.3 but should apply OK to 4.1.2.

This problem probably belongs on the autofs list. You can subscribe at
http://linux.kernel.org/mailman/listinfo/autofs

Ian



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RE: mtab and procs not in sync?

[Ian Kent]

On Tue, 8 Jun 2004, Lever, Charles wrote:

> if there are a lot of mounts on the system, then /proc/mounts can be
> truncated and not show all of them.

That's very cool.
And a timely piece of information since I was about to change autofs to 
rely on it instead of mtab.

So we can't rely on /proc/mounts being correct?
And mount consistently corrupts /etc/mtab under load.
And the util-linux list is closed and unresponsive last time I tried.

I will need to revisit this to give an account of what I think may be 
wrong with mounts mtab locking. Indeed, I have couple of questions about 
how it is supposed to work as it's not clear from the code.

Have you got any ideas how I could get the attention of the maintainer of 
mount?

Ian



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Re: mtab and procs not in sync?

[James Pearson]

Do you know how many 'a lot of mounts' is?

I believe there was a problem with /proc/mounts in 2.2 kernels (limited 
to one page) - is there still a limit in 2.4 or 2.6 kernels?

I currently symlink /proc/mounts to /etc/mtab on diskless machines to 
get round the issue that /etc/mtab can not trusted to be correct. I only 
have a maximum of a few 10's of mounts at any one time.

James Pearson

Lever, Charles wrote:
> if there are a lot of mounts on the system, then /proc/mounts can be
> truncated and not show all of them.
> 
> however, if there are more mounts in /proc/mounts than in /etc/mtab,
> there is probably a bug in mount.  not unheard of.
> 
> 
>>-----Original Message-----
>>From: Phy Prabab [mailto:phyprabab@yahoo.com] 
>>Sent: Tuesday, June 08, 2004 2:21 PM
>>To: nfs@lists.sourceforge.net
>>Subject: [NFS] mtab and procs not in sync?
>>
>>
>>Hello,
>>
>>Have run into a situation where mtab does not match
>>/proc/mounts in that mtab has numerous entries that
>>have expired off and removed, yet does not show that
>>it has been removed from mtab.  Is this known and is
>>there a fix?
>>
>>Kernel 2.4.21 and 23
>>nfs-utils 1.06
>>automount 4.1.2
>>
>>Thanks!
>>Phy
>>
>>
>>	
>>		
>>__________________________________
>>Do you Yahoo!?
>>Friends.  Fun.  Try the all-new Yahoo! Messenger.
>>http://messenger.yahoo.com/ 
>>
>>
>>-------------------------------------------------------
>>This SF.Net email is sponsored by: GNOME Foundation
>>Hackers Unite!  GUADEC: The world's #1 Open Source Desktop Event.
>>GNOME Users and Developers European Conference, 28-30th June in Norway
>>http://2004/guadec.org
>>_______________________________________________
>>NFS maillist  -  NFS@lists.sourceforge.net
>>https://lists.sourceforge.net/lists/listinfo/nfs
>>
> 
> 
> 
> -------------------------------------------------------
> This SF.Net email is sponsored by: GNOME Foundation
> Hackers Unite!  GUADEC: The world's #1 Open Source Desktop Event.
> GNOME Users and Developers European Conference, 28-30th June in Norway
> http://2004/guadec.org
> _______________________________________________
> NFS maillist  -  NFS@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/nfs
> 



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RE: mtab and procs not in sync?

[Lever, Charles]

as far as i can tell, the 4KB limit is common to x86 on 2.2 and 2.4.
2.6 has replaced the old /proc read method with seq_file, so i believe
/proc/mounts on 2.6 kernels will not suffer from this problem.

it's not a fixed number of mounts, because the length of each line in
/proc/mounts depends on what mount options are in effect.  the limit is
the number of characters in the file.

> -----Original Message-----
> From: James Pearson [mailto:james-p@moving-picture.com]=20
> Sent: Wednesday, June 09, 2004 6:29 AM
> To: Lever, Charles
> Cc: nfs@lists.sourceforge.net
> Subject: Re: [NFS] mtab and procs not in sync?
>=20
>=20
> Do you know how many 'a lot of mounts' is?
>=20
> I believe there was a problem with /proc/mounts in 2.2=20
> kernels (limited=20
> to one page) - is there still a limit in 2.4 or 2.6 kernels?
>=20
> I currently symlink /proc/mounts to /etc/mtab on diskless machines to=20
> get round the issue that /etc/mtab can not trusted to be=20
> correct. I only=20
> have a maximum of a few 10's of mounts at any one time.
>=20
> James Pearson
>=20
> Lever, Charles wrote:
> > if there are a lot of mounts on the system, then=20
> /proc/mounts can be=20
> > truncated and not show all of them.
> >=20
> > however, if there are more mounts in /proc/mounts than in=20
> /etc/mtab,=20
> > there is probably a bug in mount.  not unheard of.
> >=20
> >=20
> >>-----Original Message-----
> >>From: Phy Prabab [mailto:phyprabab@yahoo.com]
> >>Sent: Tuesday, June 08, 2004 2:21 PM
> >>To: nfs@lists.sourceforge.net
> >>Subject: [NFS] mtab and procs not in sync?
> >>
> >>
> >>Hello,
> >>
> >>Have run into a situation where mtab does not match /proc/mounts in=20
> >>that mtab has numerous entries that have expired off and=20
> removed, yet=20
> >>does not show that it has been removed from mtab.  Is this=20
> known and=20
> >>is there a fix?
> >>
> >>Kernel 2.4.21 and 23
> >>nfs-utils 1.06
> >>automount 4.1.2
> >>
> >>Thanks!
> >>Phy
> >>
> >>
> >>=09
> >>	=09
> >>__________________________________
> >>Do you Yahoo!?
> >>Friends.  Fun.  Try the all-new Yahoo! Messenger.=20
> >>http://messenger.yahoo.com/
> >>
> >>
> >>-------------------------------------------------------
> >>This SF.Net email is sponsored by: GNOME Foundation
> >>Hackers Unite!  GUADEC: The world's #1 Open Source Desktop Event.=20
> >>GNOME Users and Developers European Conference, 28-30th=20
> June in Norway=20
> >>http://2004/guadec.org=20
> _______________________________________________
> >>NFS maillist  -  NFS@lists.sourceforge.net
> >>https://lists.sourceforge.net/lists/listinfo/nfs
> >>
> >=20
> >=20
> >=20
> > -------------------------------------------------------
> > This SF.Net email is sponsored by: GNOME Foundation
> > Hackers Unite!  GUADEC: The world's #1 Open Source Desktop Event.=20
> > GNOME Users and Developers European Conference, 28-30th=20
> June in Norway=20
> > http://2004/guadec.org=20
> _______________________________________________
> > NFS maillist  -  NFS@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/nfs
> >=20
>=20
>=20


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Re: mtab and procs not in sync?

[James Pearson]

On a 2.4.26 kernel on x86 I can get /proc/mounts to go over 4K (over 8K 
with about 100 automounted file systems).

Having a quick look through the kernel code I can see seq_file used in 
relation to proc_mounts_operations (fs/proc/base.c) - however as I don't 
pretend to understand the code, I can't say this is the case ...

If 2.4.X does use seq_file, then is it safe to say /proc/mounts doesn't 
suffer from a truncation problem?

James Pearson

Lever, Charles wrote:
> as far as i can tell, the 4KB limit is common to x86 on 2.2 and 2.4.
> 2.6 has replaced the old /proc read method with seq_file, so i believe
> /proc/mounts on 2.6 kernels will not suffer from this problem.
> 
> it's not a fixed number of mounts, because the length of each line in
> /proc/mounts depends on what mount options are in effect.  the limit is
> the number of characters in the file.
> 
> 
>>-----Original Message-----
>>From: James Pearson [mailto:james-p@moving-picture.com] 
>>Sent: Wednesday, June 09, 2004 6:29 AM
>>To: Lever, Charles
>>Cc: nfs@lists.sourceforge.net
>>Subject: Re: [NFS] mtab and procs not in sync?
>>
>>
>>Do you know how many 'a lot of mounts' is?
>>
>>I believe there was a problem with /proc/mounts in 2.2 
>>kernels (limited 
>>to one page) - is there still a limit in 2.4 or 2.6 kernels?
>>
>>I currently symlink /proc/mounts to /etc/mtab on diskless machines to 
>>get round the issue that /etc/mtab can not trusted to be 
>>correct. I only 
>>have a maximum of a few 10's of mounts at any one time.
>>
>>James Pearson
>>
>>Lever, Charles wrote:
>>
>>>if there are a lot of mounts on the system, then 
>>
>>/proc/mounts can be 
>>
>>>truncated and not show all of them.
>>>
>>>however, if there are more mounts in /proc/mounts than in 
>>
>>/etc/mtab, 
>>
>>>there is probably a bug in mount.  not unheard of.
>>>
>>>
>>>
>>>>-----Original Message-----
>>>>From: Phy Prabab [mailto:phyprabab@yahoo.com]
>>>>Sent: Tuesday, June 08, 2004 2:21 PM
>>>>To: nfs@lists.sourceforge.net
>>>>Subject: [NFS] mtab and procs not in sync?
>>>>
>>>>
>>>>Hello,
>>>>
>>>>Have run into a situation where mtab does not match /proc/mounts in 
>>>>that mtab has numerous entries that have expired off and 
>>
>>removed, yet 
>>
>>>>does not show that it has been removed from mtab.  Is this 
>>
>>known and 
>>
>>>>is there a fix?
>>>>
>>>>Kernel 2.4.21 and 23
>>>>nfs-utils 1.06
>>>>automount 4.1.2
>>>>
>>>>Thanks!
>>>>Phy
>>>>
>>>>
>>>>	
>>>>		
>>>>__________________________________
>>>>Do you Yahoo!?
>>>>Friends.  Fun.  Try the all-new Yahoo! Messenger. 
>>>>http://messenger.yahoo.com/
>>>>
>>>>
>>>>-------------------------------------------------------
>>>>This SF.Net email is sponsored by: GNOME Foundation
>>>>Hackers Unite!  GUADEC: The world's #1 Open Source Desktop Event. 
>>>>GNOME Users and Developers European Conference, 28-30th 
>>
>>June in Norway 
>>
>>>>http://2004/guadec.org 
>>
>>_______________________________________________
>>
>>>>NFS maillist  -  NFS@lists.sourceforge.net
>>>>https://lists.sourceforge.net/lists/listinfo/nfs
>>>>
>>>
>>>
>>>
>>>-------------------------------------------------------
>>>This SF.Net email is sponsored by: GNOME Foundation
>>>Hackers Unite!  GUADEC: The world's #1 Open Source Desktop Event. 
>>>GNOME Users and Developers European Conference, 28-30th 
>>
>>June in Norway 
>>
>>>http://2004/guadec.org 
>>
>>_______________________________________________
>>
>>>NFS maillist  -  NFS@lists.sourceforge.net
>>>https://lists.sourceforge.net/lists/listinfo/nfs
>>>
>>
> 
> 



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RE: mtab and procs not in sync?

[Lever, Charles]

i would guess that if seq_file is used, then /proc/mounts should be OK.

i was looking at a RHEL AS 2.1 system last week that used the single
page I/O model for /proc/mounts, and it was definitely busted.

> -----Original Message-----
> From: James Pearson [mailto:james-p@moving-picture.com]=20
> Sent: Wednesday, June 09, 2004 11:05 AM
> To: Lever, Charles
> Cc: nfs@lists.sourceforge.net
> Subject: Re: [NFS] mtab and procs not in sync?
>=20
>=20
> On a 2.4.26 kernel on x86 I can get /proc/mounts to go over=20
> 4K (over 8K=20
> with about 100 automounted file systems).
>=20
> Having a quick look through the kernel code I can see=20
> seq_file used in=20
> relation to proc_mounts_operations (fs/proc/base.c) - however=20
> as I don't=20
> pretend to understand the code, I can't say this is the case ...
>=20
> If 2.4.X does use seq_file, then is it safe to say=20
> /proc/mounts doesn't=20
> suffer from a truncation problem?
>=20
> James Pearson
>=20
> Lever, Charles wrote:
> > as far as i can tell, the 4KB limit is common to x86 on 2.2 and 2.4.
> > 2.6 has replaced the old /proc read method with seq_file,=20
> so i believe
> > /proc/mounts on 2.6 kernels will not suffer from this problem.
> >=20
> > it's not a fixed number of mounts, because the length of=20
> each line in
> > /proc/mounts depends on what mount options are in effect. =20
> the limit is
> > the number of characters in the file.
> >=20
> >=20
> >>-----Original Message-----
> >>From: James Pearson [mailto:james-p@moving-picture.com]=20
> >>Sent: Wednesday, June 09, 2004 6:29 AM
> >>To: Lever, Charles
> >>Cc: nfs@lists.sourceforge.net
> >>Subject: Re: [NFS] mtab and procs not in sync?
> >>
> >>
> >>Do you know how many 'a lot of mounts' is?
> >>
> >>I believe there was a problem with /proc/mounts in 2.2=20
> >>kernels (limited=20
> >>to one page) - is there still a limit in 2.4 or 2.6 kernels?
> >>
> >>I currently symlink /proc/mounts to /etc/mtab on diskless=20
> machines to=20
> >>get round the issue that /etc/mtab can not trusted to be=20
> >>correct. I only=20
> >>have a maximum of a few 10's of mounts at any one time.
> >>
> >>James Pearson
> >>
> >>Lever, Charles wrote:
> >>
> >>>if there are a lot of mounts on the system, then=20
> >>
> >>/proc/mounts can be=20
> >>
> >>>truncated and not show all of them.
> >>>
> >>>however, if there are more mounts in /proc/mounts than in=20
> >>
> >>/etc/mtab,=20
> >>
> >>>there is probably a bug in mount.  not unheard of.
> >>>
> >>>
> >>>
> >>>>-----Original Message-----
> >>>>From: Phy Prabab [mailto:phyprabab@yahoo.com]
> >>>>Sent: Tuesday, June 08, 2004 2:21 PM
> >>>>To: nfs@lists.sourceforge.net
> >>>>Subject: [NFS] mtab and procs not in sync?
> >>>>
> >>>>
> >>>>Hello,
> >>>>
> >>>>Have run into a situation where mtab does not match=20
> /proc/mounts in=20
> >>>>that mtab has numerous entries that have expired off and=20
> >>
> >>removed, yet=20
> >>
> >>>>does not show that it has been removed from mtab.  Is this=20
> >>
> >>known and=20
> >>
> >>>>is there a fix?
> >>>>
> >>>>Kernel 2.4.21 and 23
> >>>>nfs-utils 1.06
> >>>>automount 4.1.2
> >>>>
> >>>>Thanks!
> >>>>Phy
> >>>>
> >>>>
> >>>>=09
> >>>>	=09
> >>>>__________________________________
> >>>>Do you Yahoo!?
> >>>>Friends.  Fun.  Try the all-new Yahoo! Messenger.=20
> >>>>http://messenger.yahoo.com/
> >>>>
> >>>>
> >>>>-------------------------------------------------------
> >>>>This SF.Net email is sponsored by: GNOME Foundation
> >>>>Hackers Unite!  GUADEC: The world's #1 Open Source Desktop Event.=20
> >>>>GNOME Users and Developers European Conference, 28-30th=20
> >>
> >>June in Norway=20
> >>
> >>>>http://2004/guadec.org=20
> >>
> >>_______________________________________________
> >>
> >>>>NFS maillist  -  NFS@lists.sourceforge.net
> >>>>https://lists.sourceforge.net/lists/listinfo/nfs
> >>>>
> >>>
> >>>
> >>>
> >>>-------------------------------------------------------
> >>>This SF.Net email is sponsored by: GNOME Foundation
> >>>Hackers Unite!  GUADEC: The world's #1 Open Source Desktop Event.=20
> >>>GNOME Users and Developers European Conference, 28-30th=20
> >>
> >>June in Norway=20
> >>
> >>>http://2004/guadec.org=20
> >>
> >>_______________________________________________
> >>
> >>>NFS maillist  -  NFS@lists.sourceforge.net
> >>>https://lists.sourceforge.net/lists/listinfo/nfs
> >>>
> >>
> >=20
> >=20
>=20
>=20


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Hackers Unite!  GUADEC: The world's #1 Open Source Desktop Event.
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https://lists.sourceforge.net/lists/listinfo/nfs

Re: mtab and procs not in sync?

[James Pearson]

It looks like seq_file for /proc/mounts was introduced with 2.4.19 ...

James Pearson

Lever, Charles wrote:
> i would guess that if seq_file is used, then /proc/mounts should be OK.
> 
> i was looking at a RHEL AS 2.1 system last week that used the single
> page I/O model for /proc/mounts, and it was definitely busted.
> 
> 
>>-----Original Message-----
>>From: James Pearson [mailto:james-p@moving-picture.com] 
>>Sent: Wednesday, June 09, 2004 11:05 AM
>>To: Lever, Charles
>>Cc: nfs@lists.sourceforge.net
>>Subject: Re: [NFS] mtab and procs not in sync?
>>
>>
>>On a 2.4.26 kernel on x86 I can get /proc/mounts to go over 
>>4K (over 8K 
>>with about 100 automounted file systems).
>>
>>Having a quick look through the kernel code I can see 
>>seq_file used in 
>>relation to proc_mounts_operations (fs/proc/base.c) - however 
>>as I don't 
>>pretend to understand the code, I can't say this is the case ...
>>
>>If 2.4.X does use seq_file, then is it safe to say 
>>/proc/mounts doesn't 
>>suffer from a truncation problem?
>>
>>James Pearson
>>
>>Lever, Charles wrote:
>>
>>>as far as i can tell, the 4KB limit is common to x86 on 2.2 and 2.4.
>>>2.6 has replaced the old /proc read method with seq_file, 
>>
>>so i believe
>>
>>>/proc/mounts on 2.6 kernels will not suffer from this problem.
>>>
>>>it's not a fixed number of mounts, because the length of 
>>
>>each line in
>>
>>>/proc/mounts depends on what mount options are in effect.  
>>
>>the limit is
>>
>>>the number of characters in the file.
>>>
>>>
>>>
>>>>-----Original Message-----
>>>>From: James Pearson [mailto:james-p@moving-picture.com] 
>>>>Sent: Wednesday, June 09, 2004 6:29 AM
>>>>To: Lever, Charles
>>>>Cc: nfs@lists.sourceforge.net
>>>>Subject: Re: [NFS] mtab and procs not in sync?
>>>>
>>>>
>>>>Do you know how many 'a lot of mounts' is?
>>>>
>>>>I believe there was a problem with /proc/mounts in 2.2 
>>>>kernels (limited 
>>>>to one page) - is there still a limit in 2.4 or 2.6 kernels?
>>>>
>>>>I currently symlink /proc/mounts to /etc/mtab on diskless 
>>
>>machines to 
>>
>>>>get round the issue that /etc/mtab can not trusted to be 
>>>>correct. I only 
>>>>have a maximum of a few 10's of mounts at any one time.
>>>>
>>>>James Pearson
>>>>
>>>>Lever, Charles wrote:
>>>>
>>>>
>>>>>if there are a lot of mounts on the system, then 
>>>>
>>>>/proc/mounts can be 
>>>>
>>>>
>>>>>truncated and not show all of them.
>>>>>
>>>>>however, if there are more mounts in /proc/mounts than in 
>>>>
>>>>/etc/mtab, 
>>>>
>>>>
>>>>>there is probably a bug in mount.  not unheard of.
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>-----Original Message-----
>>>>>>From: Phy Prabab [mailto:phyprabab@yahoo.com]
>>>>>>Sent: Tuesday, June 08, 2004 2:21 PM
>>>>>>To: nfs@lists.sourceforge.net
>>>>>>Subject: [NFS] mtab and procs not in sync?
>>>>>>
>>>>>>
>>>>>>Hello,
>>>>>>
>>>>>>Have run into a situation where mtab does not match 
>>
>>/proc/mounts in 
>>
>>>>>>that mtab has numerous entries that have expired off and 
>>>>
>>>>removed, yet 
>>>>
>>>>
>>>>>>does not show that it has been removed from mtab.  Is this 
>>>>
>>>>known and 
>>>>
>>>>
>>>>>>is there a fix?
>>>>>>
>>>>>>Kernel 2.4.21 and 23
>>>>>>nfs-utils 1.06
>>>>>>automount 4.1.2
>>>>>>
>>>>>>Thanks!
>>>>>>Phy
>>>>>>
>>>>>>
>>>>>>	
>>>>>>		
>>>>>>__________________________________
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>>>>
>>>>
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>>>>>>https://lists.sourceforge.net/lists/listinfo/nfs
>>>>>>
>>>>>
>>>>>
>>>>>
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RE: mtab and procs not in sync?

[Ian Kent]

On Wed, 9 Jun 2004, Lever, Charles wrote:

> i would guess that if seq_file is used, then /proc/mounts should be OK.
> 
> i was looking at a RHEL AS 2.1 system last week that used the single
> page I/O model for /proc/mounts, and it was definitely busted.

We probably need to start talking versions, back ports and vendor kernels 
to get a clear picture of the situation here.

Ian

> 
> > -----Original Message-----
> > From: James Pearson [mailto:james-p@moving-picture.com] 
> > Sent: Wednesday, June 09, 2004 11:05 AM
> > To: Lever, Charles
> > Cc: nfs@lists.sourceforge.net
> > Subject: Re: [NFS] mtab and procs not in sync?
> > 
> > 
> > On a 2.4.26 kernel on x86 I can get /proc/mounts to go over 
> > 4K (over 8K 
> > with about 100 automounted file systems).
> > 
> > Having a quick look through the kernel code I can see 
> > seq_file used in 
> > relation to proc_mounts_operations (fs/proc/base.c) - however 
> > as I don't 
> > pretend to understand the code, I can't say this is the case ...
> > 
> > If 2.4.X does use seq_file, then is it safe to say 
> > /proc/mounts doesn't 
> > suffer from a truncation problem?
> > 



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