[Cluster-devel] small inconsistency presenting fs stats between GFS1 and GFS2

[Cluster-devel] small inconsistency presenting fs stats between GFS1 and GFS2

[Fabio Massimo Di Nitto]

Hi guys,

this is purely cosmetic and I didn't prepare a patch but see this:

given a 4GB block device (just as an example):

/dev/nbd2             3,9G  518M  3,4G  14% /mnt/gfs2
/dev/nbd1             3,1G   20K  3,1G   1% /mnt/gfs

you can see that gfs1 masks the device size to hide the journals, while gfs2
shows the journal as "in use" space.

would it be possible to make gfs1 consistent with gfs2 (and probably the rest of
the world) by reporting the data in the same way? is it possible to do it
without breaking anything?

Thanks
Fabio

-- 
I'm going to make him an offer he can't refuse.

[Cluster-devel] small inconsistency presenting fs stats between GFS1 and GFS2

[Wendy Cheng]

Fabio Massimo Di Nitto wrote:
> Hi guys,
>
> this is purely cosmetic and I didn't prepare a patch but see this:
>
> given a 4GB block device (just as an example):
>
> /dev/nbd2             3,9G  518M  3,4G  14% /mnt/gfs2
> /dev/nbd1             3,1G   20K  3,1G   1% /mnt/gfs
>
> you can see that gfs1 masks the device size to hide the journals, while gfs2
> shows the journal as "in use" space.
>
> would it be possible to make gfs1 consistent with gfs2 (and probably the rest of
> the world) by reporting the data in the same way? is it possible to do it
> without breaking anything?
>
>   
I would think it is ok but this is arguable. Say in ext3 case, if the 
journal is on an external device, will you count it as "in use" space ? 
I never heard our users complain about this (maybe until now ? :) ). 
Changing this may cause some confusions with GFS1's existing 
installation base (say customers may start to complain.. after RHEL x.y, 
we start to see diskspace usage jump or something like that ?).

-- Wendy

[Cluster-devel] small inconsistency presenting fs stats between GFS1 and GFS2

[Fabio Massimo Di Nitto]

Wendy Cheng wrote:
> Fabio Massimo Di Nitto wrote:
>> Hi guys,
>>
>> this is purely cosmetic and I didn't prepare a patch but see this:
>>
>> given a 4GB block device (just as an example):
>>
>> /dev/nbd2             3,9G  518M  3,4G  14% /mnt/gfs2
>> /dev/nbd1             3,1G   20K  3,1G   1% /mnt/gfs
>>
>> you can see that gfs1 masks the device size to hide the journals, while gfs2
>> shows the journal as "in use" space.
>>
>> would it be possible to make gfs1 consistent with gfs2 (and probably the rest of
>> the world) by reporting the data in the same way? is it possible to do it
>> without breaking anything?
>>
>>   
> I would think it is ok but this is arguable.

I mean no flamewar :)

> Say in ext3 case, if the 
> journal is on an external device, will you count it as "in use" space ?

No, not really. it's not on the same device.

> I never heard our users complain about this (maybe until now ? :) ). 

It's more curiosity rather than a complain. My first concern looking at df -h
was (so to speak because I knew it was due to the journals): "3.1GB device? but
I allocated 4..."

> Changing this may cause some confusions with GFS1's existing 
> installation base (say customers may start to complain.. after RHEL x.y, 
> we start to see diskspace usage jump or something like that ?).

The free disk % won't change and yes, I understand that you would see more disk
in use, but also the real device size would increase and maintain the same balance.
Anyway I agree that it could be confusing with both approaches.

Thanks
Fabio

-- 
I'm going to make him an offer he can't refuse.