Re: terabyte+ database requirements

My company is running about 6TB of Oracle, but it is on several serververs. The largest is about 1.5 TB. We are developping an app/system that will be about 8TB of data a year after it is in place.

Our largest disk based server is an HP Unix running against an EMC disk farm, using about 2.4 TB but against multiple instances. We have another that is AIX based to optical WORMS at about 1.5TB.

We have a team of 4 DBAs and 3 sysadmins, but the above systems represent about 10 of our 45 servers. The DBAS support all the servers.

All are single box multi-processor systems with 100-200 simultaneous users. Each has about 1GB of ram, with SGAs in the 400MB range.

The largest NT server we run has about 400GB of data. It loads about 5GB of data a week. We haven't had any overwhelming problems since upgrading to 8.0.5.3.2.1 (or whatever the latest 8.0.5 is).

As was said, break out the checkbook. If you are talking major TBs, then remember disks have a mean-time-before-failure, and you could be facing frequent failures (weekly or better). Some form of raid is a necessity. 4 TB of data would require 100+ 40GB drives, 200+ raided. But that is full drives. Double that again to 400+ to allow for free space, staging areas, etc. (Does the 4TB include rollback and temp spaces?) With a mtbf of 45K hours (5 years), that is about one or two failures a week.

Pay attention to backup and recovery as well. Even with raid, you will need it. Consider O8i with partioning to make sure you can get backups of parts of tables.

Done right, Very large DataBases don't need any extra handling, and in fact can be simpler and easier to manage. Just remember that it takes 10x longer to do anything (as a DBA) on a VLDB. In article <8br5n2$pe1$1_at_nnrp1.deja.com>, jweisen_at_my-deja.com wrote:
> Tim,
>
> A couple opinions from my experience:
>
> (1) Stay away from NT (A rule I live by). A close friend of mine works
> for a company with several multi-terabyte Oracle databases, some of
 them
> under NT. They seem to have alot more problems with the NT servers
 than
> the Unix servers. Several of their databases never stop reindexing. I
> will prob get flamed for saying that, but I don't feel NT is up to
 tasks
> that large (we don't even let it serve files here).
> (2) *Lots* of RAM...I mean as much RAM as the system can hold. I would
> consider 2-4 gigs of RAM at minimum.
> (3) Lots of Fast Disks. Go with the magic Oracle configuration, use
 RAID
> 0 or 10 only (avoid RAID 5). We use a Xiotech Magnitude Storage Area
> Network Solution here. We've seen people with Mirrored Magnitudes,
 RAID
> 0 inside the box.
>
> There are other things to consider. What kind of load do you expect
 the
> system to get? 10 users? 100 users? 100,000 hits an hour? My "when all
> else fails rule of thumb is that one person can support
> 100,000$-200,000$ in hardware/software. It's not a real solid rule,
 but
> a good piece of equip (Sun E10k) with $100,000 in Oracle licenses
 should
> have at least two admins - a Unix guy and an Oracle guy. You also need
> to consider the surrounding infastructure with a system like this. If
> you get a welfare Storage Area Network Solution (under $100k) chances
> are it's "network attached", and you need to figure in an extra
 network
> engineer (watch your collisions go through the roof). You can skimp on
> manpower, but I promise you'll regret it.
>
> My suggestion is to go to someone like Sun and have them quote you a
> solution, and go from there. Try Compaq too (the DEC/Alpha stuff, not
> their PC line). See what IBM has to offer as well.
>
> Plan on a minimum of three people to devote to this though, and get
 that
> checkbook ready.
>
> Hope it helps,
> John
>
> In article <8bg0uh$r9h$1_at_nnrp1.deja.com>,
> thentzel_at_yahoo.com wrote:
> > the company i work for is considering a product offering (not a data
> > warehouse) that will generate four terabytes of data in two years
 under
> > the most optimistic usage prediction. i have been tasked with
> > estimating the number of people, nodes, etc. that will be necessary
 to
> > support this application.
> >
> > at this point, i expect to build the system on top of an oracle
> > database; but the software version and hardware have not been
 addressed
> > yet.
> >
> > basically, it would be really valuable for me to hear about
> > experiences/tribulations/costs people have encountered building and
> > managing a similar sized system.
> >
> > tia,
> > tim
> >
> > Sent via Deja.com http://www.deja.com/
> > Before you buy.
> >
> --
> **************************************************
> "One World, One Web, One Program" - Microsoft Ad
> "Ein Volk, Ein Reich, Ein Fuhrer" - Adolf Hitler
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.
>

--
Joseph R.P. Maloney, CCP,CSP,CDP
MPiR, Inc.
502-451-7404
some witty phrase goes here, I think.


Sent via Deja.com http://www.deja.com/
Before you buy.