Message-Id: <199705151413.KAA23868@delorie.com> Date: Thu, 15 May 1997 09:13:27 -0500 From: "Jonathan E. Brickman" Reply-To: "Jonathan E. Brickman" To: opendos AT delorie DOT com Subject: 16 vs. 32-bit performance Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Precedence: bulk > It's a myth that 32-bit operating systems or programs are "twice the > speed" of 16-bit programs. There's usually a slight increase, but it's > not all that big. The real difference is when the data handled by the > program is itself larger than 16 bits, for example if a program > handles numbers over 65 536 (or, usually, 32 768). A 32-bit version of > a program like PGP is *much* faster than a 16-bit version, because of > the numbers it handles. That's the exception, though. No, it's not. When I was programming regularly, most of the calculations I had to be prepared for in GUI, image-manipulation, sound-related, database-related, and almost every other area were pushing it in 16 bits. I don't know about you, but most of the files on my machine are more than 65,536 bytes long, and my hard disk is considerably larger than that. Given this, 32-bit calculation becomes an immense advantage, because one clock tick on a 32-bit CPU can often replace four or more clock ticks on a 16-bit CPU. > We're all still using 16-bit programs and systems, except those of us > using Linux, Windows NT and OS/2. Wrong. Windows 95 uses 32-bit calculation in much of its processing. Not all, but much. And nearly all of the apps on my machine run on NT 4 as well, which means they use 32-bit functionality in most cases. Not all, but most. BeOS and apps will probably replace everything I use now, in a year or two; and then, my CPU and OS will be 32-bit, and my filesystem 64-bit. Given a really decent OS for both platforms, the same amount of RAM, and comparable CPU horsepower, the 16-bit system will run more or less half as fast as the 32-bit system. The problem is, decent OSes and comparable CPUs don't really exist to support such a comparison. I would be very interested in seeing performance comparisons between an 8 MHz 80286 and an 8 MHz 386 running Minix. I'll bet it's about a 1:3 performance ratio, when Minix is optimized for each platform. Jonathan E. Brickman River City Computing, Inc. (913) 232-6663 http://www.cjnetworks.com/~rivercity brickman AT cjnetworks DOT com It seems to me that men usually think more about carburetors, and women think more about doors. I think the world needs really good carburetors...and really good doors.