Mladen, Why don't you just shut-up? I have seen your replies to other emails in a similar manner to mine. I have been using Oracle since 1987 and very well know what Metalink is. FYI, I have posted this same question on Metalink before here. I thought this list is made of some knowledgeble and helpful people, except for a few stubborns. I did do my homework, by looking at Steve Adams web-site, metalink, google and what not, but never could find anything related to ODM and these parameters, all in context of async i/o, hence this question to the list. Finally, I think my question broke no rules as far as posting to this list is concerned. It is a very legitimite question, and thankfully to Steve, I got my answer. Hope you understand, and before replying to anyone, show little concern. Thanks, Deepak --- Mladen Gogala <gogala@xxxxxxxxxxxxx> wrote: > > On 02/19/2006 10:56:11 PM, Deepak Sharma wrote: > > OS: Sun Solaris 2.8 > > Database: Oracle 10.1.0.4 > > CPU_COUNT: 32 > > > > On a database using RAW datafiles, what values > > should be specified for "db_writer_processes" > > and/or "filesystemio_options", assuming that > > "disk_asynch_io=TRUE" (also async i/o is available > at > > OS-level) ? > > There is Oracle's on-line support page called > Metalink. Its URL is > http://metalink.oracle.com. My understanding is that > this list is > not a plug-in replacement for metalink. Having said > that and given > your repeatedly demonstrated unwillingness to do > your own homework, > let me answer the question. There is a metalink note > 47328.1 with > the following title: Reference Note for Init.Ora > Parameter "DISK_ASYNCH_IO". > To some people, me included, it would look like a > clue for searching > the answers. Here is what it says: > > "DISK_ASYNCH_IO controls whether I/O to datafiles, > control files, and logfiles is asynchronous (that > is, whether parallel server processes can overlap > I/O requests with CPU processing during table > scans). If your platform supports asynchronous I/O > to disk, Oracle Corporation recommends that you > leave this parameter set to its default value. > However, if the asynchronous I/O implementation is > not stable, you can set this parameter to false to > disable asynchronous I/O. If your platform does not > support asynchronous I/O to disk, this parameter has > no effect." > > and then: > > "If DISK_ASYNCH_IO is set to FALSE, then typically > either > <Parameter:DBWR_IO_SLAVES> or > <Parameter:DB_WRITER_PROCESSES> should > be set unless the system is low throughput." > > My understanding of that is that if you have > asynchronous I/O, it will be used > automatically. DB_WRITER_PROCESSES should be > increased only if you experience > extensive waits on buffer LRU latch. IF you're using > dynamic SGA, this is automatically > computed for you, as per Metalink note 148495.1 > Finally, the filesystemio_options do not matter for > raw devices as raw devices > are not filesystem. You automatically have > asynchronous and direct I/O on raw > devices. __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com -- //www.freelists.org/webpage/oracle-l