Questions about using gvirstor as a RAID0 solution

[carlopmart]

On 10/24/2011 12:12 PM, Ivan Voras wrote:
> On 24/10/2011 11:21, carlopmart wrote:
>> Hi all,
>>
>>   I would like to use gvirstor as a thin provisioning solution for a
>> mysql server, but I have some doubts about using it:
>
> Yes, it's kind of what it was created for...
>
>> a) Do I need to put "geom_virstor_load=YES"" on loader.conf or this
>> kernel module is loaded automatically at boot If I create gvirstor
>> volume using the label option??
>
> You need to load the module yourself, the same as with other GEOM modules.
>
>> b) Does gvirstor supports UFS journaling?? For example:
>>
>>    gjournal label /dev/virstor/mydata
>>    newfs -O 2 -J /dev/virstor/mydata
>
> You can do that. It will be very inefficient (i.e. you will only avoid
> fscks, there will probably be no performance gains at all) but nothing
> should break. Both virstor and gjournal add their overheads
> (specifically, they can be seek-intensive in different ways), so you
> wouldn't want to use either if sustained random IO performance is important.
>
> On the other hand, since you are using 9-stable, you can also use the
> journaled soft-updates instead of gjournal, for much better efficiency.
>
>> c) Can i use growfs utility If I need to expand a virstor volume at
>> filesystem level??
>
> Not exactly; virstor will immediately create a volume with large virtual
> size (whatever you specify at the volume creation) ragardless of how
> many physical devices you have. If you add more physical devices to the
> virstor later, you do not have to do anything with the file system
> itself, it will still see the original large virtual size.
>
> If you are talking about expanding the virtual volume size, that's not
> implemented yet (and in that case you would need to use growfs).
>

Solved. Many thanks Ivan.

-- 
CL Martinez
carlopmart {at} gmail {d0t} com