There are some improvements in 11g regarding rebalancing performance, especially in the area of removing serialization events. I don't have enough information about your environment, but if you are using diskgroups with normal redundancy you may be hitting a known issue with ASM (10g and 11gR1) that is excessive repartnering: ASM tries to have only 10 partners per disk and this can 'cause extra work'. You can see that by querying v$asm_operation, the column EST_WORK keeps growing as the rebalancing goes on. BTW ASM disks are said partners when they have copies of at least one mirrored extent. If you want to know more about the origin of your performance problem with rebalancing I suggest you try first to look at the arbx log files in the BDUMP of the ASM instance and then possibly use a 10046 trace against those processes. If it can be of any help you can have a look at this recent presentation of mine from UKOUG2007: http://twiki.cern.ch/twiki/pub/PSSGroup/Presentations2007/Inside_Oracle_ ASM_LC_CERN_UKOUG07.ppt Cheers, Luca ________________________________ From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Finn Jorgensen Sent: Saturday, December 08, 2007 2:21 AM To: hrishys@xxxxxxxxxxx Cc: oracle-l@xxxxxxxxxxxxx Subject: Re: Stupidity with ASM rebalancing I had a 3TB diskgroup I added 2TB to and the rebalance took 3 days. Way too long and I was very nervous the whole time it should break and I'd have to start over which had happened before on smaller additions. Not sure if this has been fixed in 11g. Haven't had the time to play with it. Finn On Dec 7, 2007 5:22 AM, hrishy <hrishys@xxxxxxxxxxx> wrote: Hi Everybody here says that there is some stupidity with ASM balancing i am just wundering what problems you faced with ASM Disk reblancing and how has it been improved in 11g regards Hrishy __________________________________________________________ Sent from Yahoo! - the World's favourite mail http://uk.mail.yahoo.com <http://uk.mail.yahoo.com/> -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l