The continuing drama of RISC vs. CISC
Full Speed Ahead
Crank the compilers and turn up the system clock; maddog explains the basic differences between RISC and CISC architectures.
Recently, it was announced that Hewlett Packard had won a long-outstanding lawsuit against Oracle, citing that Oracle had violated a business agreement requiring support for the Itanium processor. I remember when the Itanium was announced. All I could do was slap my head and say, "Again?" How many times did we have to invent Ultra Wide Instruction Set Computing (UWISC) in computer science?
At that time Digital was putting all of its thrust behind a Reduced Instruction Set Computing (RISC) processor named Alpha, after years of making Complicated Instruction Set Computing (CISC) hardware, such as the PDP-11 and VAX.
The basic difference between CISC and RISC architectures is that for every instruction the programmer codes, tens, hundreds, or even thousands of tiny little instructions (called "microcode") in a CISC computer tell the hardware exactly what to do to solve a potentially complex set of tasks, whereas in a RISC computer, each machine language instruction basically does one tiny little thing. You might need tens, hundreds, or thousands of RISC instructions to do the same work as a CISC instruction – but then again, you might not. It depends on what the compiler generates.
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
Fedora 43 Has Finally Landed
The Fedora Linux developers have announced their latest release, Fedora 43.
-
KDE Unleashes Plasma 6.5
The Plasma 6.5 desktop environment is now available with new features, improvements, and the usual bug fixes.
-
Xubuntu Site Possibly Hacked
It appears that the Xubuntu site was hacked and briefly served up a malicious ZIP file from its download page.
-
LMDE 7 Now Available
Linux Mint Debian Edition, version 7, has been officially released and is based on upstream Debian.
-
Linux Kernel 6.16 Reaches EOL
Linux kernel 6.16 has reached its end of life, which means you'll need to upgrade to the next stable release, Linux kernel 6.17.
-
Amazon Ditches Android for a Linux-Based OS
Amazon has migrated from Android to the Linux-based Vega OS for its Fire TV.
-
Cairo Dock 3.6 Now Available for More Compositors
If you're a fan of third-party desktop docks, then the latest release of Cairo Dock with Wayland support is for you.
-
System76 Unleashes Pop!_OS 24.04 Beta
System76's first beta of Pop!_OS 24.04 is an impressive feat.
-
Linux Kernel 6.17 is Available
Linus Torvalds has announced that the latest kernel has been released with plenty of core improvements and even more hardware support.
-
Kali Linux 2025.3 Released with New Hacking Tools
If you're a Kali Linux fan, you'll be glad to know that the third release of this famous pen-testing distribution is now available with updates for key components.