Oracle FAQ Your Portal to the Oracle Knowledge Grid

Home -> Community -> Mailing Lists -> Oracle-L -> Re: AIX 5.2 move from JFS to JFS2

Re: AIX 5.2 move from JFS to JFS2

From: David Barbour <>
Date: Wed, 27 Jun 2007 13:37:20 -0400
Message-ID: <>


What version of AIX are you on? As you're probably aware, db_block_buffers is deprecated in favor of db_cache_size. If you're using Automatic Memory Management, you need to look at a couple of things, including pga_aggregate_target, before increasing your cache size. Best to run a statspack to get some more input. Increasing the cache size may help alleviate your issue, also check your db_file_multiblock_read count.

On 6/27/07, <> wrote:
> Now that I have upgraded our production systems from to I
> can see via truss that Oracle is taking advantage of our newly implemented
> JFS2 filesystems and opening the datafiles using CIO.
> We are experiencing higher WIO percentages since the upgrade.
> My sysadmn has suggested that perhaps I need to increase db_block_buffers
> to make up for the lack of buffering at the FS level now that we are using
> JFS2.
> Does anyone have any experience and/or thoughts regarding this?
> TIA,
> Patty
> This e-mail is confidential, intended solely for the use of the
> recipient(s) to whom it was addressed. If you have received it
> in error, please do not copy or distribute this e-mail. We ask
> that you notify us immediately by replying to the sender and
> then delete this e-mail. E-mail sent or received over the
> internet may not be secure. You should use caution when sending
> e-mail messages containing private and confidential information
> or consider other secure means to send the information. If you
> have any questions regarding the authenticity or security of
> the e-mail you have received please do not hesitate to contact
> us at 1-800-265-5615.
> Ce message de courriel est confidentiel et s'adresse uniquement
> à la personne indiquée. Si vous l'avez reçu par erreur,
> veuillez ne pas copier ni distribuer ce message de courriel.
> Nous vous demandons de nous aviser immédiatement en répondant à
> l'expéditeur, puis en supprimant ce message. Les messages
> envoyés ou reçus par courriel pourraient ne pas être sécurisés.
> Vous devriez être prudent lorsque vous envoyez des messages de
> courriel contenant des renseignements confidentiels et privés
> ou songer à prendre d'autres moyens sécurisés pour envoyer les
> renseignements. Si vous avez des questions concernant
> l'authenticité ou la sécurité d'un courriel que vous avez reçu,
> n'hésitez pas à communiquer avec nous au 1 800 265-5615.
> --

Received on Wed Jun 27 2007 - 12:37:20 CDT

Original text of this message