help: high "gc busy buffer"
From: charles <dshproperty_at_gmail.com>
Date: Tue, 11 Jan 2011 14:15:37 -0800 (PST)
Message-ID: <0448b00a-5519-478f-b3e4-893d3eebdc69_at_l7g2000vbv.googlegroups.com>
Dear group,
Date: Tue, 11 Jan 2011 14:15:37 -0800 (PST)
Message-ID: <0448b00a-5519-478f-b3e4-893d3eebdc69_at_l7g2000vbv.googlegroups.com>
Dear group,
We are using Oracle 10g on linux RAC with 4 nodes. We have a small table, no more than 300 rows, but most people will update/delete/ insert on it during load testing. And ASH report shows it is the cause of this contention.
EVENT CNT ------------------------------ ---------- gc current retry 4 gc current grant 2-way 31 gc current request 47 gc cr request 66 gc cr multi block request 69 gc current block busy 79 gc cr grant 2-way 81 gc current grant busy 113 gc current block 2-way 416 gc cr block busy 420 gc cr block 2-way 568 gc buffer busy 6448
All the "gc buffer busy" points to one small table, no index/triggers on this table, which 2000 update, 1800 insert, 1600 select. The table is created in a ASSM tablespace, so i guess freelist is not going to help here.
Could somebody give me some advice?
Thanks Received on Tue Jan 11 2011 - 16:15:37 CST