2 Replies Latest reply: May 11, 2012 5:00 AM by Rob_J RSS

    Tuning Parameters

    Krishna Nazare

      We are looking at doing scalability testing with varied load on the application. This exercise is to arrive at optimal oracle parameters values with which the application will function normally. The query is when we arrive at set of parameters and their values, whether the same values holds good across all OS platforms, or is it necessary to run the tests targeting to oracle on different OS platforms to arrive at the numbers for each OS platform. Just to be precise, we are planning to test oracle being on Sun SOLARIS, Windows 2008 R2 (64 bit) and Linux 64 bit architectures. Is it necessary to run the load tests targeting oracle on each OS platform, or the numbers arrived with one OS is applicable across all OS platforms.

      Also please let us know, some areas where the OS level tuning will be necessary for oracle (Sun Solaris, and Linux 64 bit platforms).

        • 1. Re: Tuning Parameters
          Pretty much, if your application/process/any adhoc query needs 1gb of SGA on an instance sitting on nix, it will need the same on windows. If the the database is the only thing sitting on the machine, rule of thumb is max it out as per install notes and available RAM. If it needs more tuning, cache settings, IO settings, then tune as per milage requirements.
          • 2. Re: Tuning Parameters

            It's also worth thinking about NUMA and large pages related tuning. I think large pages is on both Windows and linux/unix. The performance of it will differ depending on your system. We found that performance was worse when using NUMA and large pages on Windows, and the start up time is really long for large pages on 2008. Also, when you have fragmented memory using large pages the server will have to be rebooted when you want to restart the DB. Massive drawback in my opinion. Check out this link for a little more info on it:

            [url http://www.ora00600.com/scripts/databaseconfig/large_pages.html]Using Large Pages on Windows