Path: newssvr20.news.prodigy.com!newsmst01.news.prodigy.com!prodigy.com!rip!news.webusenet.com!peer01.cox.net!cox.net!news.maxwell.syr.edu!postnews1.google.com!not-for-mail From: pharfromhome@hotmail.com (Geomancer) Newsgroups: comp.databases.oracle.server Subject: Single-disk database and I/O load balancing? Date: 10 Oct 2003 06:27:57 -0700 Organization: http://groups.google.com Lines: 24 Message-ID: NNTP-Posting-Host: 66.82.164.29 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: posting.google.com 1065792477 15802 127.0.0.1 (10 Oct 2003 13:27:57 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Fri, 10 Oct 2003 13:27:57 +0000 (UTC) Xref: newssvr20.news.prodigy.com comp.databases.oracle.server:245003 With the Oracle10g Automatic Storage Management featre, I saw the recommendation for "stripe and mirror everywhere". But what about smaller systems on a single, large disk? There are many Oracle databases that are less than 100 gigabytes, and in my experience, a majority of Oracle systems are under 100 gig, and most fit onto a single 74 gig or 144 gig disk drive. It does not make sense to stripe across a single disk, and I experience disk euqueues, especially during large updates when undo and data blocks are simultaneously updated. I also see read enqueues when Oracle accesses index and table during the same query. I'm also curious if the newer disks like EMC and Hitachi have "fixed" read-write heads? Our existing disk have moving read-write heads, and this seek delay is over 80% of disk access latency. With the new 72 and 144 gig drives, it is hard to get my clients to buy extra disks when the existing disk is large enough to hold their entire database. These systems are always constrained by disk I/O. So, is the idea of disk load-balancing truly a fraud for non-RAIDED disks?