Second Level bitmap block contention

Version 9.2.0.8

Tablespaces are Locally managed with ASSM.

Table Pctfree 10

--

Hello All,

I am hoping you can help me explain an issue that we've been struggling with for the past month.

We have a table that is subject to concurrent deletes and inserts through pl/sql procedures that run mutli-streamed (10 streams) - each stream processes a unique

data set (products).

What we find is that randomly one or more of the streams - running the same code - will "hang" (spin) on the insert into the table.

The wait event associated with each of these sessions is a latch free wait which drilled down leads on to a 2nd level bitmap block as the hot block.