From oracle-l-bounce@freelists.org Tue Sep 13 14:10:15 2005 Return-Path: Received: from air891.startdedicated.com (root@localhost) by orafaq.com (8.12.10/8.12.10) with ESMTP id j8DJAFng029877 for ; Tue, 13 Sep 2005 14:10:15 -0500 X-ClientAddr: 206.53.239.180 Received: from turing.freelists.org (freelists-180.iquest.net [206.53.239.180]) by air891.startdedicated.com (8.12.10/8.12.10) with ESMTP id j8DJA86H029862 for ; Tue, 13 Sep 2005 14:10:09 -0500 Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 268531EC8E1; Tue, 13 Sep 2005 14:04:22 -0500 (EST) Received: from turing.freelists.org ([127.0.0.1]) by localhost (turing [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 28151-05; Tue, 13 Sep 2005 14:04:22 -0500 (EST) Received: from turing (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 9744C1EC8C6; Tue, 13 Sep 2005 14:04:21 -0500 (EST) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:reply-to:to:subject:cc:in-reply-to:mime-version:content-type:references; b=ZTuMTbf9b30xHQkVVDg3lzU0hYypJdXU2Wd2VZG0fFMgvkgNYYkkX0HuoLnoUYk/nGQgsuDxjpcM4oGj9mdSzFLD9f2c6nk1JqFalUxKvhsgTt5is8dUFqCMmtkSZCF3A6I5YXMXTrjPVHJLCX0/5MngJRtm2SB9E3FEesTeVTI= Message-ID: Date: Tue, 13 Sep 2005 20:02:28 +0100 From: David Sharples To: chiragdba@gmail.com Subject: Re: Buffer cache hit very low...!!! Cc: Oracle-L Freelists , askdba@freelists.org In-Reply-To: <1a36296005091311532cd0117a@mail.gmail.com> Mime-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_4913_7858796.1126638148471" References: <1a36296005091311532cd0117a@mail.gmail.com> X-archive-position: 25377 X-ecartis-version: Ecartis v1.0.0 Sender: oracle-l-bounce@freelists.org Errors-To: oracle-l-bounce@freelists.org X-original-sender: davidsharples@gmail.com Precedence: normal Reply-To: davidsharples@gmail.com X-list: oracle-l X-Virus-Scanned: by amavisd-new-20030616-p9 (Debian) at avenirtech.net X-mailscan-MailScanner-Information: Please contact the ISP for more information X-mailscan-MailScanner: Found to be clean X-MailScanner-From: oracle-l-bounce@freelists.org X-Spam-Level: X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on air891.startdedicated.com X-Spam-Status: No, hits=-3.5 required=5.0 tests=AWL,BAYES_00,HTML_MESSAGE, PLING_PLING autolearn=no version=2.63 ------=_Part_4913_7858796.1126638148471 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline firstly you are probably using db_cache_size new in 9i. Also why are you still using ratios? that went out with the dinosaurs. Its= =20 all about the wait interface now, find the problem which are causing your= =20 biggest waits and fix them generally ignore the ratios On 9/13/05, Chirag DBA wrote:=20 >=20 > Hi Team, > My OEM shows buffer cache hit ratio as 28% and library cache as 99%. > Another query shows different results for buffer cache. > =20 > And my db_block_buffers show value as 0. > ------=_Part_4913_7858796.1126638148471 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline
firstly you are probably using db_cache_size new in 9i.
 
Also why are you still using ratios? that went out with the dinosaurs.=   Its all about the wait interface now, find the problem which are cau= sing your biggest waits and fix them
 
generally ignore the ratios

 
On 9/13/05, = Chirag DBA <chiragdba@gmail.c= om> wrote:
Hi Team,
 
My OEM shows buffer cache hit ratio as 28% and library cache as 99%.
 
Another query shows different results for buffer cache.

And my db_block_buffers show value as 0.

------=_Part_4913_7858796.1126638148471-- -- http://www.freelists.org/webpage/oracle-l