dmd platform support - poll

[BCS]

Reply to Andrei,

> BCS wrote:
> 
>> Reply to Andrei,
>> 
>>> In my opinion, it's not application pressure that drives 64-bit
>>> machine adoption, now or in the near future. It's RAM price,
>>> availability, and usefulness. A 32-bit machine cannot gainfully have
>>> more than 4GB of RAM, period.
>>> 
>> IIRC 32 bit Intel chips can address more like 64GB of RAM (I can't
>> find
>> the ref but I seem to recall about 4 extra address bits). It's just
>> virtual address spaces that are limited to 4GB (or 2-3GB after the OS
>> takes it's pound of flesh)
>> As pointed out, only a few apps need anything near 2GB of RAM per
>> process.

found a ref:  

http://msdn.microsoft.com/en-us/library/aa366778.aspx
http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1168664

the CPU limit has to be >=128GB (look at Server 2003) or it might be 64GB 
(re linux)

> Even if only a few apps need anything near 2GB of RAM per process,
> their sum will exceed that limit rather quickly, which gives strong
> justification to 64-bit OSs. (Not sure if you meant to basically say
> the same.)

Most people will not have problems with 2GB/process limits, those that do 
can go 64bit. Most people won't have much use for more than about 8-16GB 
total of RAM and those are well within the CPU's limit (but outside the OS's 
[vista/XP]).

My point is that few people are pushing either the per process or system 
total memory limits of the x86-32bit CPUs and need something that only 64bit 
CPU's will give them. (OTOH you might need 64bit to run the OS you need to 
get at enough RAM)

> 
> The real problem is that there are applications that need as much
> memory as they could possibly get, and for those dmd simply offers no
> option.

Agree. Compilers seem to need to be written for the corner cases. "No one 
will ever need to do that" is never a valid answer.

> 
> Andrei
>