Path: newssvr20.news.prodigy.com!newsmst01.news.prodigy.com!prodigy.com!newsfeed.telusplanet.net!newsfeed2.telusplanet.net!newsfeed.telus.net!edtnps84.POSTED!not-for-mail From: Glen A Stromquist User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.4) Gecko/20030624 X-Accept-Language: en-us, en MIME-Version: 1.0 Newsgroups: comp.databases.oracle.server Subject: Re: 9i, pfiles and spfiles References: <3f85ea99$0$28118$afc38c87@news.optusnet.com.au> <1Eqhb.4476$XS4.953@edtnps84> <3f866097$1$30614$afc38c87@news.optusnet.com.au> <3f86d230$0$15134$afc38c87@news.optusnet.com.au> In-Reply-To: <3f86d230$0$15134$afc38c87@news.optusnet.com.au> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Lines: 92 Message-ID: Date: Fri, 10 Oct 2003 15:56:39 GMT NNTP-Posting-Host: 216.123.238.50 X-Trace: edtnps84 1065801399 216.123.238.50 (Fri, 10 Oct 2003 09:56:39 MDT) NNTP-Posting-Date: Fri, 10 Oct 2003 09:56:39 MDT Xref: newssvr20.news.prodigy.com comp.databases.oracle.server:245043 Howard J. Rogers wrote: > Glen A Stromquist wrote: > > >>Hi Howard - glad I could help! > > > I'm sure you just did all of this so that I could learn, didn't you ;-) > > >>Fixing it was no problem, by the end of the day yesterday I'd figured >>out that compatible=9.2 was needed because of my system tablespace and >>it was starting ok, so this morning just re-created an spfile from it >>and all's ok, although I'm still reading to find out why I want to do >>this over the old init file. > > > See below. > > >>I was using Kedit when I edited the original spfile, which must have >>changed it to a text file when saved. At least now I know that a "*." in >>front of a parameter does not affect the startup. > > > > True. And it will work just fine if, in an init.ora, you leave the * out as > well. "*" just means 'all instances'. So does a lack of a "*". And that > betrays the real reason why the spfile was invented: RAC. Because in a RAC > you might want one instance to have an 80M shared pool, and the other to > have 120M. So how do you distinguish between the two settings? You have: > > INST1.shared_pool_size=80M and > INST2.shared_pool_size=120M > > The the right settings apply to the right instance. By the way, the command > to set that up in an spfile would be: > > alter system set shared_pool_size=80M scope=spfile sid='INST1'; and > alter system set shared_pool_size=120M scope=spfile sid='INST2'; > > By default, the sid clause will be set to "*", so that by default any alter > system that affects the spfile will apply to all instances in the RAC. > > By the way, the instance.parameter notation works perfectly well with a > boring old init.ora, too. But the init.ora, being a mere text file, can't > be dropped onto a raw partition... and unless you have gone to the expense > of putting a cluster file system onto your shared disk (or taken the > slightly brave step of using the freebie CFSes that Oracle have produced > for Linux and Windows) then that must mean you can't have one init.ora that > can be used to control the entire set of instances comprising your RAC. > Hence the need for a binary version of the init.ora, which can indeed be > dropped onto a raw partition. > > The other reason for Oracle switching to an spfile is that precisely because > it's binary, the only thing that can edit it is your server process. And > that's good, because it means the file is immune from the stupidity of > users who think that including comments, explanations and change history > within the init.ora is a good idea... it actually just results in an > enormous mess which no computer system could hope to manage properly. So a > binary version means that managing the file and, the important bit, making > changes to it *automatically* becomes feasible. And in 9iR2 there's at > least one bit of functionality that does precisely that: Data Guard. When > you suddenly decide that you want one of your standby databases to be > updated at a lag of 30 minutes instead of the current 15, that actually > means 'change my LOG_ARCHIVE_DEST_3 parameter to include a DELAY clause'... > but by talking to DMON (the Data Guard Broker) to request the change, you > actually get DMON to modify the spfile for you, so you don't have to worry > about *how* to implement the change, merely request *what* you want to > change. So if you want Data Guard in 9iR2, you absolutely have to have an > spfile. > > And that's a long-winded way of saying, the spfile will become more and more > important to Oracle as a way of hiding from the user *how* to do things, > and thus allow him or her to concentrate more of what it is they want done. > If you want a self-tuning database, too, you're going to have to have this > 'I will automate the configuration changes needed to secure a particular > outcome' facility. > > Regards > HJR Got it, I was going to blow away the spfile and stick with init files, but since this is a sandbox anyway I may as well keep it and get used to it... BTW, if you are using Linux a lot now you may want to try "gqlplus", kind of a shell to run sqlplus in and allows use of the arrow keys to scroll thru your sql commands like a dos window, very slick but I have to figure out why it fills the sql buffer when I get time.