[Rd] compiling R | multi-Opteron | BLAS source

[Evan Cooch]

>
> I think the early version of ACML lagged behind others, but recent
>  versions are competitive.  I've run into precision problem (failing
>  make check all) with some Goto BLAS before.  Also, Goto BLAS has 
> switched to a more restrictive license (probably not a problem for 
> you though).
>   

No, probably not a problem for us at this end, but good to know. I'm 
happy to give the latest version of ACML a try. In fact, it occurred to 
me that it would probably be worth comparing relative performance. I 
know that benchmarking is a technical issue, but I would be curious to 
see how some of our compute-intensive jobs perform.

>  
>   
>> 3) compilation of BLAS - I can compile for 32-bit, or 64-bit. 
>> Presumably, given we've invested in 64-bit chips, and a 
>> 64-bit OS, we'd like to consider a 64-bit compilation. Which, 
>> also presumably, means we'd need 64-bit compilation for [R]. 
>> While I've read the short blurb on CRAN concerning 64-bi vs 
>> 32-bit compilations (data size vs speed), I'd be happy to 
>> have both on our machine. But, I'm not sure how one specifies 
>> 64-bits in the [R] compilation - what flags to I need to set 
>> during ./configure, or what config file do I need to edit?
>>     
>
> That's up to the compiler(s) you use (unstated).  For GCC, I believe
> -m64/-m32 is the flag.  For 64-bit GCC -m64 is the default.
>
> Andy
>   

Thanks indeed.