DB on raid array

I have a Dell 2650 server with a 15 drive powervault attached. the power
vault has 15 146gb drives arranged into one raid5 logical drive in order to
hold my 1.1tb read only delivery table.
I am wondering if it is better to have one large drive that has one Sql
Server primary file spread over all the drives, or is it better to segment
the raid array into numerouse drives and segment the database into numerouse
data files each on its own drive letter.
Any comments would be most appreciated.
thanks!Thats a tough question.
For the sake of maintaining your DB then one file spread across all the
raids as probably best, however performance is going to be a bit og a pig.
However according to SQL Server 2000 Performance Tuning (page 79 paragraph
1) "Another general guideline is to spread your data across as many disk
drives as possible to allow for more parallel disk access".
Out of curiosity have you worked out where your system and log files are
going to live ?, only it may require different raiding.
If you want further infor then I am leaving for home in about 10 min, but my
email is peternolan67@.REMOVETHIShotmail.com.
Peter
"Carl Henthorn" wrote:
> I have a Dell 2650 server with a 15 drive powervault attached. the power
> vault has 15 146gb drives arranged into one raid5 logical drive in order to
> hold my 1.1tb read only delivery table.
> I am wondering if it is better to have one large drive that has one Sql
> Server primary file spread over all the drives, or is it better to segment
> the raid array into numerouse drives and segment the database into numerouse
> data files each on its own drive letter.
> Any comments would be most appreciated.
> thanks!|||My current config is to have the data file on the logical drive. this spreads
the file over the 15 drives, so I already have 15 drives servicing the data
drive. My log file is on the CPU unit, but is not used much as the db is read
only.
"Peter Nolan" wrote:
> Thats a tough question.
> For the sake of maintaining your DB then one file spread across all the
> raids as probably best, however performance is going to be a bit og a pig.
> However according to SQL Server 2000 Performance Tuning (page 79 paragraph
> 1) "Another general guideline is to spread your data across as many disk
> drives as possible to allow for more parallel disk access".
> Out of curiosity have you worked out where your system and log files are
> going to live ?, only it may require different raiding.
> If you want further infor then I am leaving for home in about 10 min, but my
> email is peternolan67@.REMOVETHIShotmail.com.
> Peter
>
> "Carl Henthorn" wrote:
> > I have a Dell 2650 server with a 15 drive powervault attached. the power
> > vault has 15 146gb drives arranged into one raid5 logical drive in order to
> > hold my 1.1tb read only delivery table.
> >
> > I am wondering if it is better to have one large drive that has one Sql
> > Server primary file spread over all the drives, or is it better to segment
> > the raid array into numerouse drives and segment the database into numerouse
> > data files each on its own drive letter.
> > Any comments would be most appreciated.
> > thanks!|||After sending the response I had a think that at least multiple datafiles,
whether they are put on different drives is going to be a good idea, mainly
because the size of your database is going to be that big that backing it up
is going to be a real problem, however you can back up independant datafiles.
You could also create one set of raid 0+1 disks (or even raid 5's) purely
for the non clustered indexes on say the 'D' drive with the actual data on a
different set of disk (i.e. the E drive), though creating the tables is going
to be a bit of a pain, you will get some parellel querying.
You will need quite a bit of space to do this however on the index disks
though.
Then you can split your tables into as many different datafiles you can
comfortably get away with on your non indexed raid 5, so you can back up the
datafiles.
One not of concern though is that log files do have a real habit of
increasing when your not expecting it.
Hope this helps, but now I am off home ;)
Peter
"Carl Henthorn" wrote:
> My current config is to have the data file on the logical drive. this spreads
> the file over the 15 drives, so I already have 15 drives servicing the data
> drive. My log file is on the CPU unit, but is not used much as the db is read
> only.
> "Peter Nolan" wrote:
> > Thats a tough question.
> >
> > For the sake of maintaining your DB then one file spread across all the
> > raids as probably best, however performance is going to be a bit og a pig.
> >
> > However according to SQL Server 2000 Performance Tuning (page 79 paragraph
> > 1) "Another general guideline is to spread your data across as many disk
> > drives as possible to allow for more parallel disk access".
> >
> > Out of curiosity have you worked out where your system and log files are
> > going to live ?, only it may require different raiding.
> >
> > If you want further infor then I am leaving for home in about 10 min, but my
> > email is peternolan67@.REMOVETHIShotmail.com.
> >
> > Peter
> >
> >
> >
> > "Carl Henthorn" wrote:
> >
> > > I have a Dell 2650 server with a 15 drive powervault attached. the power
> > > vault has 15 146gb drives arranged into one raid5 logical drive in order to
> > > hold my 1.1tb read only delivery table.
> > >
> > > I am wondering if it is better to have one large drive that has one Sql
> > > Server primary file spread over all the drives, or is it better to segment
> > > the raid array into numerouse drives and segment the database into numerouse
> > > data files each on its own drive letter.
> > > Any comments would be most appreciated.
> > > thanks!