I assume you're talking about using ASM disk groups with hardware striping and then striping again within ASM? HP has a paper on this at: http://h71028.www7.hp.com/enterprise/downloads/4AA0-9728ENW_ASM_EVA_Best _Practices_White_Paper_final%20121806.pdf Obviously this is using their hardware but it deals with double striping and their findings. I haven't checked the stats for our systems, but I don't believe I would ever be opposed to implementing something that would allow additional throughput unless there were inherent risks that outweighed the increases. Chris Taylor Sr. Oracle DBA Ingram Barge Company Nashville, TN 37205 Office: 615-517-3355 Cell: 615-354-4799 Email: chris.taylor@xxxxxxxxxxxxxxx ________________________________ From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Baumgartel, Paul Sent: Wednesday, November 14, 2007 9:35 AM To: oracle-l Subject: How much I/O service time? For your busiest and most critical production systems, how much of total database service time (Top 5 Timed Events in Statspack or ASH reports) is I/O: db file sequential read, db file scattered read, db file parallel write? Some people at my shop want to move to double striping on the new server we'll be moving to, on the grounds that we'll need it when volumes grow from the current 2 or 3 million trades/day to as many as 10 million. At the moment, db file sequential read and db file parallel write typically total about 15% of total database time, which I think is acceptable. I just need a reality check, so any info you can give me will be appreciated. Thanks, Paul Baumgartel CREDIT SUISSE Information Technology Securities Processing Databases Americas One Madison Avenue New York, NY 10010 USA Phone 212.538.1143 paul.baumgartel@xxxxxxxxxxxxxxxxx www.credit-suisse.com <file:///\\www.credit-suisse.com> ======================================================================== ====== Please access the attached hyperlink for an important electronic communications disclaimer: http://www.credit-suisse.com/legal/en/disclaimer_email_ib.html ======================================================================== ======