i686? i386?

chillu · 2009-01-19 16:12:35

What does i686 optimized mean?
How is it different from the i386 tag that I see on some other distros?

I have a Core 2 Duo E4300. Does that change anything?

u_no_hu · 2009-01-19 16:43:00

http://ww.letmegooglethatforyou.com/?q= … ed+mean%3F

chillu · 2009-01-19 17:07:59

Hmm.. haven't compiled much myself. Explains why I don't know stuff.
Thanks anyway!

u_no_hu · 2009-01-19 17:17:48

Its the new Forum policy to reply only with google

bluewind · 2009-01-19 17:24:58

i368 works on older processors; i686 only on "newer" ones.

chillu · 2009-01-19 17:28:56

u_no_hu wrote:

Its the new Forum policy to reply only with google

For having missed something that obvious I guess I deserved it anyway
I did wiki i386 and i686 but didn't gather much from it and then went for the forums straight!

Devastator · 2009-01-19 17:53:39

I think that you know, that i386, i486, ... i686 and so on are the identifiers of the processors families (architectures) - the greater, the newer one. Every next family have some new instructions added to the previous set (so you can do the same thing in shorter time - i.eg. using the single new instruction instead of several older ones).
So - i686 optimized application should be faster than i386 optimized app, though i686 won't run on older architectures, because i686 optimized application uses instructions that were not present on older architectures (processor cannot execute unknown command).

I hope it is clear (I know that my english is not perfect )

Ramses de Norre · 2009-01-19 18:16:40

Devastator wrote:

Every next family have some new instructions added to the previous set (so you can do the same thing in shorter time - i.eg. using the single new instruction instead of several older ones).

In fact, Intel mostly added small simple instructions to their instruction sets to _avoid_ using the big complex ones that do a lot in one instruction. Using a sequence of simple (RISC) instructions that do just one thing is faster then using the complex (CISC) instructions, due to pipelining advantages, simplified control units and the generality of those simple instructions.

(I had an exam on computer architecture earlier today, sorry but I couldn't resist to make use of my newly earned knowledge )

Ranguvar · 2009-01-19 18:26:14

Ah, but while that holds true in the olden days, complex do-it-all instructions are becoming more advantageous - they become the "simple" instructions, and there's more and more complex ones that will eventually be the fastest.

doorknob60 · 2009-01-20 06:30:39

u_no_hu wrote:

http://ww.letmegooglethatforyou.com/?q= … ed+mean%3F

Lol this thread is the second result on there :-P

Anyways i386 means it's compatible with any x86 CPU (Like the original 386, 486, Pentium, etc). 486 is same thing pretty much, but 486 and better. i586 mean Pentium and better. i686 means Pentium 3 and better (or in AMD terms of things, K6-2 and better). If it's compiled for i686, that means it's optimized to use the new features found on Pentium 3 CPUs and higher that aren't found on older CPUs, meaning it will run faster. The only downside to this is that it won't run on CPUs older than the features (like my old laptop with a K6 (not -2) ). Anyways, if you have a Core 2 Duo (like you said you did), go for the x86_64 version, optimized for 64 bit processors, for an ever better boost (as well as increased memory support, etc, and future proofness). If I'm wrong about anything, correct me, because I just said what I've understood it to be, in pretty simplified terms.

Zeist · 2009-01-20 06:37:15

doorknob60 wrote:

u_no_hu wrote:
http://ww.letmegooglethatforyou.com/?q= … ed+mean%3F
Lol this thread is the second result on there :-P
Anyways i386 means it's compatible with any x86 CPU (Like the original 386, 486, Pentium, etc). 486 is same thing pretty much, but 486 and better. i586 mean Pentium and better. i686 means Pentium 3 and better (or in AMD terms of things, K6-2 and better). If it's compiled for i686, that means it's optimized to use the new features found on Pentium 3 CPUs and higher that aren't found on older CPUs, meaning it will run faster. The only downside to this is that it won't run on CPUs older than the features (like my old laptop with a K6 (not -2) ). Anyways, if you have a Core 2 Duo (like you said you did), go for the x86_64 version, optimized for 64 bit processors, for an ever better boost (as well as increased memory support, etc, and future proofness). If I'm wrong about anything, correct me, because I just said what I've understood it to be, in pretty simplified terms.

Actually, i386 isn't compatible with any x86 CPU since it won't run on a 286 or on a 8086.

tomk · 2009-01-20 07:10:59

doorknob60 wrote:

i686 means Pentium 3 and better

Pentium Pro or better, actually.

corstar · 2009-01-20 08:39:06

"let me google that for you"
Best.website.ever

Dieter@be · 2009-01-20 11:36:17

doorknob60 wrote:

u_no_hu wrote:
http://ww.letmegooglethatforyou.com/?q= … ed+mean%3F
Lol this thread is the second result on there :-P

lol, recursive loop

Ramses de Norre · 2009-01-20 11:43:10

Ranguvar wrote:

Ah, but while that holds true in the olden days, complex do-it-all instructions are becoming more advantageous - they become the "simple" instructions, and there's more and more complex ones that will eventually be the fastest.

Intel newest architecture, IA-64 (not to be mistaken for AMD64 or EM64T, the 64 bit extensions of IA-32 which are what the athlon64 and core2duo's etc implement), is a real RISC architecture.. It is implemented in the newest Itanium2 processors.

Devastator · 2009-01-20 12:03:27

True - RISC architecture is faster, because it is easier to optimize processor itself for simple commands, than to the complex ones, BUT they still have troubles with backward compatibility - they have to keep old commands in order to make older applications work...

Therefore I am waiting for netbooks with ARM processors, which does not have all this x86 troubles, as they have completly different architecture (if I am not wrong, they are RISC?), and requires much less power to work, so perhaps they may be capable of working for more than 4-5 hours...

Ramses de Norre · 2009-01-20 15:49:22

Devastator wrote:

True - RISC architecture is faster, because it is easier to optimize processor itself for simple commands, than to the complex ones, BUT they still have troubles with backward compatibility - they have to keep old commands in order to make older applications work...
Therefore I am waiting for netbooks with ARM processors, which does not have all this x86 troubles, as they have completly different architecture (if I am not wrong, they are RISC?), and requires much less power to work, so perhaps they may be capable of working for more than 4-5 hours...

Well, the newest Intel processors use a full RISC architecture, they aren't compatible with IA-32 anymore (Intel has a software emulator for older programs). They are only available for servers through the itanium processors ATM, and it's not sure whether they will become available on desktops, some argue that compatibility issues will force Intel to stay with the current AMD64 architecture. I truly hope IA-64 gets pushed forward though, it looks very promising

proc · 2009-02-20 20:15:15

doorknob60 wrote:

The only downside to this is that it won't run on CPUs older than the features (like my old laptop with a K6 (not -2) ).

But you could use my Archlinux-i586 for that laptop! Take a look at http://code.google.com/p/archlinux-i586/

Arch Linux

#1 2009-01-19 16:12:35

i686? i386?

#2 2009-01-19 16:43:00

Re: i686? i386?

#3 2009-01-19 17:07:59

Re: i686? i386?

#4 2009-01-19 17:17:48

Re: i686? i386?

#5 2009-01-19 17:24:58

Re: i686? i386?

#6 2009-01-19 17:28:56

Re: i686? i386?

#7 2009-01-19 17:53:39

Re: i686? i386?

#8 2009-01-19 18:16:40

Re: i686? i386?

#9 2009-01-19 18:26:14

Re: i686? i386?

#10 2009-01-20 06:30:39

Re: i686? i386?

#11 2009-01-20 06:37:15

Re: i686? i386?

#12 2009-01-20 07:10:59

Re: i686? i386?

#13 2009-01-20 08:39:06

Re: i686? i386?

#14 2009-01-20 11:36:17

Re: i686? i386?

#15 2009-01-20 11:43:10

Re: i686? i386?

#16 2009-01-20 12:03:27

Re: i686? i386?

#17 2009-01-20 15:49:22

Re: i686? i386?

#18 2009-02-20 20:15:15

Re: i686? i386?

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