On Tue, Nov 11, 2014 at 10:49 AM, Hameed, Amir <Amir.Hameed@xxxxxxxxx> wrote: > · I/O scheduler – The default scheduler is Completely Fair > Queuing (CFQ). However, it seems that for the Oracle Unbreakable Linux > kernel, the DEADLINE I/O scheduler is the default. For Red Hat, what do > people normally set it to for highly IO intensive ERP systems? The Deadline scheduler is preferred for Databases, as the 'completely fair queuing' mechanism seems to be a misnomer when applied to databases. Here's a redhat note: https://access.redhat.com/solutions/54164 Pretty sure there are some MOS Notes re this, though it has been a few weeks since looking at schedulers, and I don't recall the notes at the moment. ... What the heck, looked one up for you: Linux: Should 'CFQ Scheduler' or 'DEADLINE Scheduler' Be Used In Oracle RAC? (Doc ID 1352304.1) Jared Still Certifiable Oracle DBA and Part Time Perl Evangelist Principal Consultant at Pythian Pythian Blog http://www.pythian.com/blog/author/still/ Oracle Blog: http://jkstill.blogspot.com Home Page: http://jaredstill.com