In order to avoid a religious war I'll just offer this: Look at: http://h71028.www7.hp.com/ERC/downloads/4AA0-7923ENW.pdf This document shows that RAID5 (7D+1P : page 10 right graph) is far better than RAID 1(2D+2D : page 9 left graph) both on read and write operation. From a price/performance perspective RAID5 beats RAID10 by quite a bit. Also, today's high end storage arrays have a very fast asic chips and large cache that make the two very competitive. Personally I've done numerous muti-terabyte (20TB-75TB) DW benchmarks using RAID5 and have had no complaints on the performance. Depending on how dirty you want your hands to get... pick up Oracle Orion tool [http://www.oracle.com/technology/software/tech/orion] and do some read & write tests. You might want to use some discretion with the BAARF stuff. I think much of it is outdated. Storage technology has probably changed quite a bit since 2000. CPUs certainly have. Another resource is: http://www.storageperformance.org/results/benchmark_results_spc2 Many of the arrays have been tested at both RAID5 and mirroring. Check the reports for the details. On 10/4/07, ryan_gaffuri@xxxxxxxxxxx <ryan_gaffuri@xxxxxxxxxxx> wrote: >I have read the BAARF articles about RAID and write intensive Oracle >databases. Are any of these problems mitigated with RAID 5 7+1. I did some >googling, but the 7+1 part is not really clear. Has anyone worked with >this? -- Regards, Greg Rahn http://structureddata.org -- //www.freelists.org/webpage/oracle-l