32-bit to 64-bit - Obsolesence Pains Again? 184
robotsrule asks: "Having been in the computer industry a while I distinctly remember the pain of making the 16-bit to 32-bit transition, when Windows made the change to 32-bit support. Any developer who remember the joys of thunking and other kludges that were meant to help code conversions also remembers the arcane marathon debug sessions too. I have not been keeping up with the latest Microsoft Longhorn technical news, or the plans that the Linux community has for 64-bit platform support. Does anyone out there have a reliable prediction for the amount of system shock we are facing when either Longhorn or 64-bit Linux comes out? Will I lose all my favorite 32-bit development tools again as I watch the backward compatibility support dry up as the 64-bit O/S platforms are adopted? Or are the O/S manufacturers making happy noises about long-term support for existing development languages and tools?"
64-bit linux (Score:4, Informative)
64-bit linux (Score:5, Informative)
Umm.. no offense, but where have you been? 64-bit linux has been out for a LONG time. Some platforms have been 64-bit kernelspace (sparc64, ppc64, alpha, amd64) and have had 64-bit userspace (alpha) while others have had a mixed 32-bit and 64-bit userspace (sparc, mips, ppc, amd64).
Most open source apps are already ported. Are you really doing things at a low enough level where you have to worry about thunking?? You might have bigger problems then.
-molo
*WHEN* 64-bit linux comes out? (Score:4, Informative)
As for the Windows side, the lessons of the 16->32 conversion were not wasted, abstract types created for that conversion are still in use, and will certainly make the new transition much easier. There will be some bugs that will need to be shaken out, but it's unlikely to be the sort of major effort it was last time.
Re:64 bit linux :-)? (Score:2, Informative)
I have the same setup, but I cannot say that I'm not missing anything. Although almost everything I use is open source and can therefore be ported and, for the most part, has been ported, there are a few closed programs whose binaries haven't been ported that I miss a little bit.
There are more, but those are the basics... I hope the move of the general public to 64-bit is quick so that the few closed-source programs that I still use will be ported!
Re:64 bit linux :-)? (Score:5, Informative)
flash, java, and ATI on amd64 (Score:2, Informative)
Bitness != Pain (Score:4, Informative)
Porting from 16-bit Windows applications to 32-bit Windows is sort of comparible to the problems you face running Windows applications under Linux using WINE. In both cases, you're going to a new OS, and relying on a compatibility layer.
A 32-bit Windows application running under 64-bit Windows just won't face these issues. There will be some 64-bit features it won't be able to uses, that's all.
Re:Bitness != Pain (Score:1, Informative)
Re:Bitness != Pain (Score:2, Informative)
Re:Oh yeah, what about Java? (Score:5, Informative)
Defined that way by the language standard and will always be that way on any platform past, present, and future. That's why it's platform-neutral, because you don't have to deal with ridiculous low-level issues like the size of standard datatypes. All primitive types are fixed by the language standard. These sizes do not change from one machine architecture to another (as do in most other languages). This is one of the key features of the language that makes Java so portable.
Need more than 2,147,483,647? Try long -- 9,223,372,036,854,775,807. Still not big enough? java.math.BigInteger is arbitrary precision.
Although programming in Java has lost some of its charm for me, I never ever again want to have to program in a language where I don't know from one platform to the next whether or not a particular bit of arithmetic will overflow.
The difference... (Score:5, Informative)
You don't need them to get around the 4GB limit (no need for PAE), and no operating system was using segment protection of memory anyway; relying solely on page protection flags.
Everything in 64-bit mode ends up in a known, fixed location of memory (like on old Macs)
The difference...? (Score:2, Informative)
If I remember my history right, it was the 286 that added this mode. Granted the addressing was in 24 bit but it tossed out haveing to split up your memory address across 2 pointer registers ( I still curse those damn data segments, when I'm drunk enough).
Re:64-bit linux (Score:2, Informative)
Re:64 bit linux :-)? (Score:2, Informative)
* dev-java/blackdown-jre
Latest version available: 1.4.2.01-r1
Latest version installed: [ Not Installed ]
Size of downloaded files: 28,483 kB
Homepage: http://www.blackdown.org/ [blackdown.org]
Description: Blackdown Java Runtime Environment 1.4.2.01
License: sun-bcla-java-vm
* dev-java/sun-jre-bin [ Masked ]
Latest version available: 1.5.0.03
Latest version installed: [ Not Installed ]
Size of downloaded files: 32,042 kB
Homepage: http://java.sun.com/j2se/ [sun.com]
Description: Sun's J2SE Platform
License: sun-bcla-java-vm
Re:How hard is it, (Score:4, Informative)
Don't let you be fooled by the fact that 16->32, and 32->64 seems similar and infer that 64->128 is the same.
First the exponential increase in performance/memory size gives you a linear increase in bit count. Doubling the bit count is a very rare event.
Second, hitting a limit on 64 bits would mean 4 billion times 4 billion bytes.
Think about it. 73 millions of 250 gigabytes hard drive *per* application.
All the movies from imdb.com, in DVD format, in memory. 4500 times.
An DiVX of your whole life. 43 thousands times.