[Spam? ] Re: ZFS snapshot name length limit? (File name too long)

[Michiel Detailleur]

Pawel Jakub Dawidek wrote:
> On Wed, Mar 10, 2010 at 03:14:59PM +0100, Michiel Detailleur wrote:
>   
>> This seems to imply a maximum length of 72 characters (snapshot '@' sign 
>> excluded) for *usable* snapshots? (usable in the sense that we can 
>> mount/look into them)
>>
>> What limit am I (we?) hitting here? Is this a problem with ZFS itself or 
>> with FreeBSD? Sure looks like a silly limit for the filesystem that 
>> touts 'biggest everything'.
>>     
>
> From looking at the code, I think you hitting this limit:
>
> This is FreeBSD limit caused by statfs structure:
>
> /*
>  * filesystem statistics
>  */
> [...]
> #define MNAMELEN        88              /* size of on/from name bufs */
> [...]
>
> ZFS mounts snapshots on lookup and this is this mount that fails.
>   
So all that would need to be done to allow mounting snapshots with 
longer names would be to increase this value? (I'm not a C programmer, 
so bear with me :) )

Is that something you could commit a change for as the ZFS committer? Or 
is there more to it than that?

In any case: thanks for your answer and for all your hard work in 
getting ZFS in FreeBSD! :)

Michiel