Sorry to early.. meant that it might "NOT" be the right solution for you :) On Thu, Dec 24, 2009 at 9:07 AM, Thomas Roach <troach@xxxxxxxxx> wrote: > Hi, > > Are you doing a lot of inserts/updates to tables that have indexes that are > populated by sequences? You should find the objects the contention is on. To > assist with this, take a look at this page. > http://www.ardentperf.com/2007/09/12/gc-buffer-busy-waits-in-rac-finding-hot-blocks/ > > Basically what "could" be happening (what happened with me) was that I had > a bunch of sessions across nodes all fighting to put entries into the same > index blocks. Even on one node, this would be a contention issue. What I did > to fix my issue was identify the indexes with the contention and made them > reverse key indexes. With reverse key indexes you lose the ability to > perform certain operations like an index range scan. So if you do queries > where something is between this value and that value etc, it might be the > right solution for you. > > Good Luck. > > > > > On Thu, Dec 24, 2009 at 8:28 AM, Pradeep Chetal < > Pradeep.Chetal@xxxxxxxxxxxxxx> wrote: > >> >> >> Folks, >> >> >> >> We have an app that is running well in single instance but when put on a >> 2-node or 3-node RAC, we see pretty much similar performance. However, if >> the CPU time is 55-60% in single instance, it becomes 20% in 3-node RAC and >> top-5 itmed events become.. >> >> >> >> "gc buffer busy", "gc current block busy", "enq: TX- index contention >> >> >> >> Any help in what to look for will be greatly appreciated. >> >> >> >> Thanks, >> >> >> >> -- Pradeep >> >> *Pradeep Chetal* >> Sr. Director - Infrastructure Architecture >> ------------------------------ >> *Mformation Technologies Inc.* >> *Switchboard:* +1 732 692 6200 >> >> >> Visit >> *WWW.MFORMATION.COM* and see how the MFORMATION SERVICE MANAGER can help >> you to transform your business >> >> Please consider the environment before printing >> This message and the information contained herein is proprietary and >> confidential and subject to the Mformation Confidentiality policy >> statement, >> you may request a copy by emailing info@xxxxxxxxxxxxxx >> > > > > -- > Thomas Roach > 813-404-6066 > troach@xxxxxxxxx > -- Thomas Roach 813-404-6066 troach@xxxxxxxxx