To continue to add performance benefit ideas:

Check the output of logstat - in particular the log buffer size and
number of log buffers.

The Ingres defaults are the minimum configuration - if you are doing
any sort of high IO processing, increasing them can potentially provide
a large performance increase.

Increasing the number of log buffers to 16 and the size to 16K increases the
amount of memory Ingres will use to buffer writes to the log file (which 
can be a major bottleneck).

Chekc the "log splits" and "log waits" in logstat output compared to the 
number of transactions. Increase the number and size of the log buffers
and after running for a reasonable amount of time, check the figures again.

You should see many less waits for free log buffers, and less splits.

Changing these parameters is done with the rcpconfig utility.

It is a little ugly to use.. One way is to shut down ingres, run
csinstall to install the shared memory segments, then run rcpconfig.

Good Luck,
Sean Riley
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