Re: Responsiveness of Server at high CPU load

On Thu, 18 Dec 2003 01:17:39 +0100, Rick Denoire <100.17706_at_germanynet.de> wrote:

>OK, here we go.
>4 GB RAM, about 3.5 were used by four instances, two of them 8.1.7,
>the other two 9.2.0.4. Number of concurrent users: perhaps 3 at max.
>(these are mostly test instances, used by specific developers for
>specific issues).

The Oracle guideline is that SGA shouldn't consume not more than about one third of physical RAM. In your case it consumes almost all of it. Your system is simply starving, and is faulting and swapping like hell.
Apart from not being familiar with the guideline (which has been posted many, many times here), what on earth made you think the configuration you have is sensible? In your situation there is severe lack of memory and I guess even the O/S is usually paged out!

Also, if you already need 3.5 G for 4 test instances, where you and your 'developers' routinely must have solved performance problems by cranking up init.ora parameters, how do you think this is EVER going to perform into production (ie NOT throwing everything you have right out of the window, and starting all over again)?

--
Sybrand Bakker, Senior Oracle DBA