[ On Tue, January 31, 1995 at 11:15:47 (-0800), Ted Lemon wrote: ]
> Subject: Re: Why the partitioning should stay the same 
>
> Database performance is a very different beast from swap performance.
> One of the primary reasons for going to raw disks is so that you can
> guarantee synchronization.  Otherwise you have to use Unix-style
> synchronization, which is comparitively expensive, and generally not a
> good fit for a DBMS.  Swap, on the other hand, requires no special
> synchronization, so RDBMS performance requirements really don't apply.

That all depends on what you're measuring.  I've seen raw DBMS (i.e. w/o
locking of any sort) change in performance by nearly double when going
to a raw disk vs. UNIX filesystem (Pyramid DC-OS/x & Oracle).

Like it or not, the UNIX filesystem adds a measurable amount of overhead.

-- 
						Greg A. Woods

+1 416 443-1734			VE3TCP		robohack!woods
Planix, Inc. <woods@planix.com>; UniForum Canada <woods@uniforum.ca>