Re: SAN/NAS options

The Apple is, as you say, cheap (except, the Apple markup on the disks
fuzzes that a bit). Its easy to set up, and has been quite reliable for me,
but do not expect anything resembling good DB performance out of it (I gave
up running anything but backup DBs on it). From the mouth of Apple guys, it
(and Xsan) are heavily optimized for sequential access. They want to sell
piles of these to the music/film industry, where they have some cred. Oracle
has apparently gotten some performance gains through raw device pixie dust
and voodoo, but even as a (reluctant, kicking-and-screaming) Oracle guy I
wouldn't go there.

Other goofy things about it: it isn't 1 device with 14 disks and redundant
controllers. Its 2 7 disk arrays with non-redundant controllers. It doesn't
do RAID10.

If you want a gob-o-space with no performance requirements, its fine.
Otherwise...

On 12/14/05 1:56 AM, "Charles Sprickman" <spork(at)bway(dot)net> wrote:

> Hello all,
>
> It seems that I'm starting to outgrow our current Postgres setup. We've been
> running a handful of machines as standalone db servers. This is all in a
> colocation environment, so everything is stuffed into 1U Supermicro boxes.
> Our
> standard build looks like this:
>
> Supermicro 1U w/SCA backplane and 4 bays
> 2x2.8 GHz Xeons
> Adaptec 2015S "zero channel" RAID card
> 2 or 4 x 73GB Seagate 10K Ultra 320 drives (mirrored+striped)
> 2GB RAM
> FreeBSD 4.11
> PGSQL data from 5-10GB per box
>
> Recently I started studying what we were running up against in our nightly
> runs
> that do a ton of updates/inserts to prep things for the tasks the db does
> during the business day (light mix of selects/inserts/updates). While we have
> plenty of disk bandwidth (according to bonnie), we are really dying on IOPS.
> I'm guessing this is a mix of a rather anemic RAID controller (ever notice how
> adaptec doesn't publish any real performance specs on raid cards?) and having
> only two or four spindles (effectively 1 or 2 on writes).
>
> So that's where we are...
>
> I'm new to the whole SAN thing, but did recently pick up a few used NetApp
> shelves and a Fibre Channel RAID HBA (Mylex ExtremeRAID 3000, also used) to
> toy
> with. I started wondering if I could put something together to both get our
> storage on one set of boxes and allow me to get data striped across more
> drives. Our budget is not huge and we are not adverse to getting used gear
> where appropriate.
>
> What do you folks recommend? I'm just starting to look at what's out there
> for
> SANs and NAS, and from what I've seen, our options are:
>
> NetApp Filers - the pluses with these are that if we use NFS, we don't have to
> worry about either large filesystem support in FreeBSD (2TB practical limit),
> or limitation on "growing" partitions as the NetApp just deals with that. I
> also understand these make backups a bit simpler. I have a great, trusted,
> spare-stocking source for these.
>
> Apple X-Serve RAID - well, it's pretty cheap. Honestly, that's all I know
> about it - they don't talk about IOPS numbers, and I have no idea what lurks
> in
> that box as a RAID controller.
>
> SAN box w/integrated RAID - it seems like this might not be a good choice
> since
> the RAID hardware in the box may be where I hit any limits. I also imagine
> I'm
> probably overpaying for some OEM RAID controller integrated into the box. No
> idea where to look for used gear.
>
> SAN box, JBOD - this seems like it might be affordable as well. A few big
> shelves full of drives a SAN "switch" to plug all the shelves and hosts into
> and a FC RAID card in each host. No idea where to look for used gear here
> either.
>
> You'll note that I'm being somewhat driven by my OS of choice, FreeBSD. Unlike
> Solaris or other commercial offerings, there is no nice volume management
> available. While I'd love to keep managing a dozen or so FreeBSD boxes, I
> could be persuaded to go to Solaris x86 if the volume management really shines
> and Postgres performs well on it.
>
> Lastly, one thing that I'm not yet finding in trying to educate myself on SANs
> is a good overview of what's come out in the past few years that's more
> affordable than the old big-iron stuff. For example I saw some brief info on
> this list's archives about the Dell/EMC offerings. Anything else in that vein
> to look at?
>
> I hope this isn't too far off topic for this list. Postgres is the main
> application that I'm looking to accomodate. Anything else I can do with
> whatever solution we find is just gravy...
>
> Thanks!
>
> Charles
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 5: don't forget to increase your free space map settings