Hi Steve, I had initiated the process of gradual migration to bind variables. It seems it will take a long time. Thanks for your detailed answer, I appreciate it
Ed > Hi Ed, > > Of course, I'd suggest that the application be enhanced to use bind variables appropriately! ;-) > > In the interim, I would introduce a script such as 'keeper.sql' from the Ixora web site to keep all the reusable > material in the library cache so as to reduce the impact of the flushes. Once that is working as desired, I would > increase the flush frequency to an interval of say 1 hour or 30 minutes. The size of the library cache and thus shared > pool utilization will still grow over time, but more slowly. I would then reduce the shared pool size to approximately > the size that it grew to after 1 day of normal application usage. To then mitigate the risk of ORA-4031 errors I would > ensure that 'shared_pool_reserved_size' is allowed to default, but set '_shared_pool_reserved_min_alloc' to its minimum > value (which is 4000 or 5000, version dependent). An instance restart once a week would be good too if you can manage > that. > > @ Regards, > @ Steve Adams > @ http://www.ixora.com.au/ - For DBAs > @ http://www.secularislam.org/call.htm - For Muslims > @ http://www.christianity.net.au/ - For all > > > -----Original Message----- > From: Edward Shevtsov [mailto:[EMAIL PROTECTED]] > Sent: Friday, 19 October 2001 19:09 > To: Steve Adams; [EMAIL PROTECTED] > Subject: Re: distribution of the sleeps on the library cache latches > > > Hi Steve, > > yes, you're absolutely right. I've inhereted that system. The > shared_pool_size = 750M. I believe it's HUGE and oversized. The application > code is mostly based on literal SQL. The miss rate on the shared pool is > normally about 15%-20% with periodical peaks up to 50%. But the previous DBA > insist that we shouldn't decrease the size of shared pool as the miss rate > will be much higher. He also setup periodical flushing every 3 hours (I > assume he did it in order to prevent ORA-4031). > If I undestand the things right, deacresing of shared_pool_size will > decrease load on shared pool latch _but_ contention on the library latches > will be higher because of higher parse rate. Is it correct and what's your > advice in my case? > > Thanks in advance, > Ed > -- Please see the official ORACLE-L FAQ: http://www.orafaq.com -- Author: Edward Shevtsov INET: [EMAIL PROTECTED] Fat City Network Services -- (858) 538-5051 FAX: (858) 538-5051 San Diego, California -- Public Internet access / Mailing Lists -------------------------------------------------------------------- To REMOVE yourself from this mailing list, send an E-Mail message to: [EMAIL PROTECTED] (note EXACT spelling of 'ListGuru') and in the message BODY, include a line containing: UNSUB ORACLE-L (or the name of mailing list you want to be removed from). You may also send the HELP command for other information (like subscribing).
