MDF and LDF at the same drive

Dear All,
My Database Server is using RAID 5.
I put the mdf and ldf file of my database at the same drive.
Does it affect the SQL Server Performance?
Thanks
Robert LieThe best thing would be not to use Raid 5 due to performance.
For best overall performance, locate the database files (.mdf) and log files
(.ldf) on separate arrays in your server to isolate potentially conflicting
reads and writes. [6.5, 7.0, 2000] Updated 12-20-2004
*****
To store your database files (.mdf), the best performance is gained by
storing them using RAID 10 arrays. If this is too expensive, then RAID 5 is
the next best bet. Each RAID array (5 or 10) should have as many physical
disks in the array as the controller will support. This allows reads and
writes to be performed simultaneously on each physical drive in the array,
significantly boosting disk I/O. [6.5, 7.0, 2000] Updated 12-20-2004
From: http://www.sql-server-performance.com/sql_server_setup.asp
HTH, Jens Suessmeyer.
http://www.sqlserver2005.de
"Robert Lie" <robert.lie24@.gmail.com> schrieb im Newsbeitrag
news:%23xPXnqWSFHA.2788@.TK2MSFTNGP09.phx.gbl...
> Dear All,
> My Database Server is using RAID 5.
> I put the mdf and ldf file of my database at the same drive.
> Does it affect the SQL Server Performance?
> Thanks
> Robert Lie|||Hi Robert,
yes but it only becomes a problem in very large databases, the ldf (log
file) should be on a drive of its own in a perfect world and using RAID5 for
it is overkill and will slow it's performance as the log file is written to
sequentially and most other things including the mdf file are written to
randomly. Again this is only a concirn is big installations and if you have
a spare physical drive then the ldf file could be put on that.
--
Regards
Alex White MCDBA MCSE
http://www.intralan.co.uk
"Robert Lie" <robert.lie24@.gmail.com> wrote in message
news:%23xPXnqWSFHA.2788@.TK2MSFTNGP09.phx.gbl...
> Dear All,
> My Database Server is using RAID 5.
> I put the mdf and ldf file of my database at the same drive.
> Does it affect the SQL Server Performance?
> Thanks
> Robert Lie|||Hi,
It is always recommended to put Data files and Log files in multiple drives,
it will be even better if you put the files in drives belongs to different
disk controllers.
This will help you to reduce the disk I/O and eventually the better
performance.
But incase if your volume pd transaction is less then you may not have any
I/O issues, inthis case you can keep both the files in same drives which
belongs to same disk controller. And monitor the Disk Queue length , all
hardware resorce usage using Perfmon.
If you find every thing is normal then you are good. See the website
http://www.sql-server-performance.com/ for more performanace monitoring and
tuning options.
Thanks
Hari
SQL server MVP
"Robert Lie" <robert.lie24@.gmail.com> wrote in message
news:%23xPXnqWSFHA.2788@.TK2MSFTNGP09.phx.gbl...
> Dear All,
> My Database Server is using RAID 5.
> I put the mdf and ldf file of my database at the same drive.
> Does it affect the SQL Server Performance?
> Thanks
> Robert Lie