[Gluster-users] To GlusterFS or not...

[Chris Knipe]

Hi,

SSD has been considered but is not an option due to cost.  SAS has
been considered but is not a option due to the relatively small sizes
of the drives.  We are *rapidly* growing towards a PB of actual online
storage.

We are exploring raid controllers with onboard SSD cache which may help.

On Tue, Sep 23, 2014 at 7:59 AM, Roman <romeo.r at gmail.com> wrote:
> Hi,
>
> just a question ...
>
> Would SAS disks be better in situation with lots of seek times using
> GlusterFS?
>
> 2014-09-22 23:03 GMT+03:00 Jeff Darcy <jdarcy at redhat.com>:
>>
>>
>> > The biggest issue that we are having, is that we are talking about
>> > -billions- of small (max 5MB) files. Seek times are killing us
>> > completely from what we can make out. (OS, HW/RAID has been tweaked to
>> > kingdom come and back).
>>
>> This is probably the key point.  It's unlikely that seek times are going
>> to get better with GlusterFS, unless it's because the new servers have
>> more memory and disks, but if that's the case then you might as well
>> just deploy more memory and disks in your existing scheme.  On top of
>> that, using any distributed file system is likely to mean more network
>> round trips, to maintain consistency.  There would be a benefit from
>> letting GlusterFS handle the distribution (and redistribution) of files
>> automatically instead of having to do your own sharding, but that's not
>> the same as a performance benefit.
>>
>> > I’m not yet too clued up on all the GlusterFS naming, but essentially
>> > if we do go the GlusterFS route, we would like to use non replicated
>> > storage bricks on all the front-end, as well as back-end servers in
>> > order to maximize storage.
>>
>> That's fine, so long as you recognize that recovering from a failed
>> server becomes more of a manual process, but it's probably a moot point
>> in light of the seek-time issue mentioned above.  As much as I hate to
>> discourage people from using GlusterFS, it's even worse to have them be
>> disappointed, or for other users with other needs to be so as we spend
>> time trying to fix the unfixable.
>> _______________________________________________
>> Gluster-users mailing list
>> Gluster-users at gluster.org
>> http://supercolony.gluster.org/mailman/listinfo/gluster-users
>
>
>
>
> --
> Best regards,
> Roman.



-- 

Regards,
Chris Knipe