comps discussion at fudcon and the future

[Matthew Woehlke]

Florian Festi wrote:
> Matthew Woehlke wrote:
>> Florian Festi wrote:
>>> Multilib:
>>> The situation has changed a lot since we introduced multilib. The
>>>  challenge who is going to support 64bit processors first has
>>> been decided long ago and the age of 32bit processors is ending.
>>
>> No it isn't. [snip]
> 
> Ok, I should probably a bit more precise: 32 bit being default on 64 bit 
> capable computers is coming to an end as the default RAM size for 
> desktops goes beyond 4GB.

Yes, that's better :-). That said, why on earth would you want to run 
32-bit processes on a 64-bit OS when 64-bit flavors are available?

I can think of exactly two reasons. One, there is no 64-bit version 
available (which is rare with Free Software, but can happen if you have 
some proprietary software you need to run). Two, because you are 
building 32-bit programs intended to be shipped to a 32-bit-only OS.

Other than that, my experience seems to be that 32-bit processes on a 
64-bit OS run slower than pure 64-bit flavors, but the above are IMO 
both valid reasons to keep multilib around.

>> Other than perhaps binutils, why would you ever have a 32-bit binary 
>> on a 64-bit system? ;-) Or do you include libs in "binaries"?
> 
> There are several reasons to do so: Third party software that is not build
> for 64 bit, software like firefox that uses plugins that are only available
> in 32 bit, building software or content for 32 bit and may be some more.

Okay, basically the same list I came up with :-).

> Multilib is not going to go away in the sense that you still will be 
> able to 32 bit software on a 64 bit installation. But it already got 
> away in the sense that we do no longer install 32 bit libs by default. 

Ah. Yes, this is a good thing. No one should ever have i*86 libraries 
installed on an x86_64 system unless they have specifically asked for 
them. :-) (I count 'installing something with i*86 dependencies as 
"specifically asking".)

It sounds like we are generally in agreement.

-- 
Matthew
Please do not quote my e-mail address unobfuscated in message bodies.
-- 
"I can hear you / just barely hear you / I can just barely hear you"
   -- "I Can Hear You", by They Might Be Giants