Global temporary table data is stored in the temporary tablespace (where no redo will be generated on the DML operations). When DML operations are performed on global temporary table, for read consistency undo must be generated. Such undo records are written to undo tablespace, and thus redo generated on the undo writes. If you perform […]
Program Global Area (PGA) in Oracle database is a private memory region that contains the data and control information for a server process. PGA is allocated per server process, used for storing run-time area of cursor, sorting, bitmap merge, etc. Automatic PGA management in Oracle Database was managed by two parameters up until 11gR2 – […]
Changing The Number Of Oracle Database 12c Log Writers
In an Oracle Database 12c instance you will likely see multiple log writer (LGWR) background processes. When you first start the Oracle instance you will likely see a parent and two redo workers. This is a very big deal and something many of us have been waiting for - for many years!
While I'm excited about the change, if I can't control the number of LGWRs (more...)
Off May Not Be Totally Off: Is Oracle In-Memory Database 12c (18.104.22.168.0) Faster?
Most Oracle 12c installations will NOT be using the awesome Oracle Database in-memory features available starting in version 22.214.171.124.0. This experiment is about the performance impact of upgrading to 12c but disabling the in-memory features.
Every experiment I have performed comparing buffer processing rates, clearly shows any version of 12c performs better than 11g. (more...)