zfs discuss - Oct 2006 - zone with lofs zfs - why legacy

I''ve created a zone which should mount the /pool1/flexlm.ulo zfs via
lofs:

+ zfs create pool1/flexlm.ulo
+ zfs set atime=off pool1/flexlm.ulo
+ zfs set sharenfs=off pool1/flexlm.ulo

+ zonecfg -z flexlm
...
 add fs
         set dir=/usr/local
         set special=/pool1/flexlm.ulo
         set type=lofs
         add options rw,nodevices
 end
...

This seems to work. However the manual zfs(5) say, that the mountpoint property
has to be set to legacy.
1) why ?
2) if one sets the zfs property to legacy, the manual does not say, how an
/etc/vfstab entry should look like (and a mount_zfs man page doesn''t
exist)...
3) the /pool1/flexlm.ulo property is set to atime=off. Do I need to specifiy
this option or something similar, when creating the zone?
4) Wrt. best performance, only , what should one prefer: add fs:dir or add
fs:dataset ?
 
 
This message posted from opensolaris.org

Hello Jens,

Monday, October 23, 2006, 7:15:39 PM, you wrote:
JE> 3) the /pool1/flexlm.ulo property is set to atime=off. Do I need
JE> to specifiy this option or something similar, when creating the zone?

no, you don''t.

JE> 4) Wrt. best performance, only , what should one prefer: add fs:dir or
add fs:dataset ?

The performance should be the same in both cases - only a difference
in features.

ps. of course you do realize that mounting a filesystem over lofs will
    degrade performance


-- 
Best regards,
 Robert                            mailto:rmilkowski at task.gda.pl
                                       http://milek.blogspot.com

''Robert Milkowski wrote:''
>
Hi Robert,
>
> Monday, October 23, 2006, 7:15:39 PM, you wrote:
> JE> 3) the /pool1/flexlm.ulo property is set to atime=off. Do I need
> JE> to specifiy this option or something similar, when creating the
zone?
>
> no, you don''t.
OK.
> JE> 4) Wrt. best performance, only , what should one prefer: add fs:dir
or add fs:dataset ?
>
> The performance should be the same in both cases - only a difference
> in features.
> ps. of course you do realize that mounting a filesystem over lofs will
>     degrade performance
Yes, I guessed that, but hopefully not that much ...
Thinking about it, it would suggest to me (if I need abs. max. perf): the best
thing to do is, to create a pool inside the zone and to use zfs on it ?

Regards,
jens.
 
 
This message posted from opensolaris.org

Jens Elkner wrote:
> Yes, I guessed that, but hopefully not that much ...
> Thinking about it, it would suggest to me (if I need abs. max. perf): the
best
> thing to do is, to create a pool inside the zone and to use zfs on it ?
Using a ZFS filesystem within a zone will go just as fast as in the 
global zone, so there''s no need to create multiple pools.

--matt

> Using a ZFS filesystem within a zone will go just as
> fast as in the 
> global zone, so there''s no need to create multiple
> pools.
So, Robert is actually wrong (at least in theory): using a zfs via
add:fs:dir..,type=lofs gives probably less performances than using it via
add:dataset:name. Correct?
 
 
This message posted from opensolaris.org

Hello Jens,

Tuesday, October 24, 2006, 5:09:38 AM, you wrote:
>> Using a ZFS filesystem within a zone will go just as
>> fast as in the 
>> global zone, so there''s no need to create multiple
>> pools.
JE> So, Robert is actually wrong (at least in theory): using a zfs
JE> via add:fs:dir..,type=lofs gives probably less performances than
JE> using it via add:dataset:name. Correct?
JE>  


Adding just ZFS file system into a zone should give the same
performance as delegating entire dataset. Now exposing ZFS file system
over LOFS into a zone should give you less performance - how much? I
don''t know.

-- 
Best regards,
 Robert                            mailto:rmilkowski at task.gda.pl
                                       http://milek.blogspot.com

Hello Robert,

Tuesday, October 24, 2006, 9:15:57 AM, you wrote:

RM> Hello Jens,

RM> Tuesday, October 24, 2006, 5:09:38 AM, you wrote:
>>> Using a ZFS filesystem within a zone will go just as
>>> fast as in the 
>>> global zone, so there''s no need to create multiple
>>> pools.
JE>> So, Robert is actually wrong (at least in theory): using a zfs
JE>> via add:fs:dir..,type=lofs gives probably less performances than
JE>> using it via add:dataset:name. Correct?
JE>>  


RM> Adding just ZFS file system into a zone should give the same
RM> performance as delegating entire dataset. Now exposing ZFS file system
RM> over LOFS into a zone should give you less performance - how much? I
RM> don''t know.


To be clear:

1. add fs; set type=zfs; set special=pool/fs; set dir=/opt/fs; end

2. add dataset; set name=pool/fs; end

Both should give the same performance.

-- 
Best regards,
 Robert                            mailto:rmilkowski at task.gda.pl
                                       http://milek.blogspot.com