our solution was a patch for 6376915 (for oracle version 10204) It helped. After that another LOB event (sorry, I've forgot the details) poped-out but for that we knew what to do - LOB cache helped (thanks to small LOB size.) Brgds, Laimis N --------------------------------------------------------------------------------- Please consider the environment before printing this e-mail From: fmhabash <fmhabash@xxxxxxxxx> To: Oracle L <oracle-l@xxxxxxxxxxxxx> Date: 2011.04.05 22:52 Subject: Using RDBMS 10.2.0.3: Have You Experienced Enq: Hwm - Contention? We go hit by this event recently and would like validate the scenario and the proposed solutions against your experience if you encountered it. This event affected a LOB segment in an ASSM tablespaces in a RAC database. This is what I have found so far ... 1) As temporary workaround, manually add extra space to the LOB segment. 2) Bug 6376915 (affecting 10.2.0.3) - >= 10.2.0.4: EVENT="44951 TRACE NAME CONTEXT FOREVER, LEVEL < 1 - 1024 >" - set PCTVERSION to 100: but never able to use blocks freed by updated blobs 3) Bug 6413373 (LOB in RAC and ASSM) - Lob HW enqueue contention: LOBs in ASSM tablespaces - Set FREEPOOLS is set to a value >= the number of instances - Partition the table into a number of partitions sufficient 4) Try alter system set"_insert_enable_hwm_brokered"=false If you did encounter this issue, what was you rca and final resolution? Thank you. -- //www.freelists.org/webpage/oracle-l -- //www.freelists.org/webpage/oracle-l