On Wed, Dec 10, 2003 at 02:50:11PM +0100, Matthias Waldhauer wrote:
> Back to the topic:
> Some time ago there was a discussion going on regarding the use of large 
> memory pages. In a mersenneforum thread I collected some info regarding 
> new linux kernels and some real world results published in a paper.
> Here some extracts:
> Linux kernel versions 2.5.36+ and 2.6 include a "HugeTLBs" patch, which 
> allows an application to allocate large memory pages.
> Also 64bit Windows Server seems to support them too:
> http://msdn.microsoft.com/library/default.asp?url=/library/en-us/memory/base/large_page_support.asp
> My thoughts about the possilibities:
> Oracle managed to get a 8% speedup by using the large pages. Although I 
> have little experience in this area I think for FFTs the speedup will be 
> much larger

I agree!  I have been thinking about the exact same thing.

I'm in the process of writing (not quite finished or working ;-) some
code which you load as an LD_PRELOAD library under linux.  This gets
its fingers into the memory allocation, and makes all malloc space
come from hugetlbfs (how you get large pages under linux).

My primary user for this was to be mprime of course!

When finished this should be an easy way of trying any application
with large pages without having to modify it.

I haven't finished the code yet, but it shouldn't take long,
especially if people are asking for it!

Nick Craig-Wood
Unsubscribe & list info -- http://www.ndatech.com/mersenne/signup.htm
Mersenne Prime FAQ      -- http://www.tasam.com/~lrwiman/FAQ-mers

Reply via email to