partitioned tables on SAn drives

[mahajanakhil198]

We've recently purchased new servers with SAN drives as auxiliary storage in addition to auxilary storage on server.
Question is:
will table and index partitioning be of any use if RAID 5 is implemented??

[PAVB]

You partition either to help query performance or help during purge processes.

Why would RAID 5 storage have any impact on that?

[mahajanakhil198]

my issue is query performance.
see:
1. if v use a 4 disk RAID 5, 3 of them will keep data blocks n 1 will be parity(distributed) block.
2. i make 4 partitions of a table. if i dont use RAID structure, then i cud have reduced I/O by allocating 4 partitions to 4 diff tablespaces(datafiles corresponding to each tablespace could be kept on a diff disk).
3. same 4 partitions of a table with RAID 5 structure..Wen all data is striped, then we cant assure dat queries specific to 1 partiton will access only 1 disk. Thus wen queries corresponding to each partition execute simultaneously, there may be contention for disk controller, thus affecting the query performance.

[davey23uk]

you only have a finite number of disk controllers anyway

do you really understand RAID, and how it has no impact the way you can setup your database

[mahajanakhil198]

yes i do understand RAID but I dont know how RAID affects database setup in anyway..
As I thought it cud have an impact on performance of queries on partitioned objects in my previous post in this thread. So, dont know much abt its impact on partitoned tables , but it is recommended by oracle too dat it is generally not a good idea to have redologs on striped disks that use RAID 5.

[PAVB]

I'm not following what could be the relationship in between redologs and partitioned tables.

[Thomasps]

Just some 'tips' won't work when come to database implementation. You should know everything from Oracle, System, OS to application. Otherwise you will be creating bottlenecks in one or other place. I saw one application which was working faster in a normal PC but failed to achieve the same performnace in a high end server (interestingly the server was installed by the Vendor, one of the global gaint the market!) just because of RAID-5 and lower RAID Controller memory along with smaller stripe size.

So, "I don't know " will lead to another round of end user performance complaints. Grab DBAs / Application Architects/ SYS Admin and discuss with them. Good luck.

[abhaysk]

(interestingly the server was installed by the Vendor, one of the global gaint the market!)

i can smell whom you may be hinting at :-)