Message-Id: <10563.112420@fatcity.com> From: Trassens Christian Date: Wed, 19 Jul 2000 12:28:41 -0300 Subject: RE: Multiple Buffer Pool There is something that it doesn't sound good. When you pin packages, = you do it on the shared pool. When you keep tables, you do it on the buffer = cache. More specific: code, as PL/SQL, procedures, and SQL, runs using the = shared pool as a cache. The data blocks goes to the buffer. Through 8 you can specify two areas in the buffer cache, known as buffer keep and buffer recycle.=20 Talking deeply about those things. From my experience and my tests I = can advise you testing with small tables and indexes used for application. = Add their blocks. And with that in mind set the value of buffer_keep. At = least include an overhead of 20%. Also estimate the amount of lru_latches for = that buffer. BUT REMEMBER THAT IS TEST AND TRY with these new features. With = my advice I can tell you that I always gain some percent of performance. However your case is different, so test it. About the shared_pool I always pin packages when I notice shared pool fragmentation problems. Before this I usually set = shared_pool_reserved_size to a value near 10%/15% of the shared_pool_size. And when you realise = about that kind of problems: looking at x$kghlu and v$sgastat and at last = when you receive a 4031 error. Regards. NOTE: Remember that before setting the value of buffer keep or recycle, = you must issue the alter table....buffer stmt on the table. > -----Mensaje original----- > De: Gautam_Reddy@Dell.com [SMTP:Gautam_Reddy@Dell.com] > Enviado el: Mi=E9rcoles 19 de Julio de 2000 12:39 > Para: Multiple recipients of list ORACLE-L > Asunto: Multiple Buffer Pool >=20 > Hi > =20 > Just want to how many of you pin system packages in the keep pool. If = so > what kind of performance improvement have you seen. I have been doing = some > test on pinning some of the system packages and I have not seen much = of > improvement. I even pinned my lookup(static) tables into the keep = pool to > and I have not seen any performance gain.=20 > =20 > Any other suggestions on how to optimal set keep,recycle pool are = also > welcomed.=20 > =20 > Thx > Gautam Reddy > 728-3656(512) > gautam_reddy@dell.com