Re: [Beowulf] A cluster for material simulation

2007-12-03 Thread Mark Hahn
be familliar with this kind of system and then extend it to around 20 nodes. Tasks size could vary between 1G to let say 10G. 10G is quite modest, especially for 20 nodes (ram is cheap!). are you sure you need a cluster? a single nicely configured SMP system will handle 10G jobs quite neatly,

Re: [Beowulf] NFS Read Errors

2007-12-03 Thread Mark Hahn
does the same thing with a slightly simpler syntax. There is mounting evidence that you should use sha1sum rather than md5sum. for general checking, md5 is still fine (ie not security-related stuff). I am guessing you are using TCP NFS mounts as well? TCP forces retries in the event of bad p

[Beowulf] Re: CSharifi Next generation of HPC

2007-12-03 Thread Mark Hahn
C-Sharifi Cluster Engine: The Second Success Story on "Kernel-Level OK, how about providing some meaty content? google shows me that you've put this fairly content-light PR on several groups and websites. as Usability. Although the latter belief was hard to realize, a sample why was it h

Re: [Beowulf] NFS Read Errors

2007-12-03 Thread Joe Landman
Hi Michael: Michael H. Frese wrote: We were having trouble restarting from our homegrown parallel magnetohydrodynamic code's checkpoint files. The files could be read, but funny things happened in the run afterward. Eventually we figured out that the restarted parallel run differed from the

[Beowulf] NFS Read Errors

2007-12-03 Thread Michael H. Frese
We were having trouble restarting from our homegrown parallel magnetohydrodynamic code's checkpoint files. The files could be read, but funny things happened in the run afterward. Eventually we figured out that the restarted parallel run differed from the serial restarted run from the same ch

[Beowulf] A cluster for material simulation

2007-12-03 Thread Guillaume MICHAL
Good morning all, Our faculty is thinking about a cluster for material simulations. At the moment we would like to use FEM, MD, MPM and maybe in some cases a multiscale FEM/MD or MPM/MD. We will start with a very small cluster around 5 nodes to be familliar with this kind of system and then

Re: [Beowulf] Using Autoparallel compilers or Multi-Threaded libraries with MPI

2007-12-03 Thread Greg Lindahl
On Mon, Dec 03, 2007 at 10:29:56PM +, [EMAIL PROTECTED] wrote: > True, enough ... one must consider both the kinetic and > thermodynamic requirements for existence, but I was thinking that the > system was perhaps at equilibrium by now. No, people keep on producing hybrid codes and finding th

Re: [Beowulf] Using Autoparallel compilers or Multi-Threaded libraries with MPI

2007-12-03 Thread Gerry Creager
Greg Lindahl wrote: On Mon, Dec 03, 2007 at 09:47:41PM +, [EMAIL PROTECTED] wrote: I think that the number of real-world apps in this class is perhaps not large, or there would be more hybrid code. Ah, but you've missed the random element here: People start writing hybrid code before they

Re: [Beowulf] Using Autoparallel compilers or Multi-Threaded libraries with MPI

2007-12-03 Thread richard . walsh
-- Original message -- From: Greg Lindahl <[EMAIL PROTECTED]> > On Mon, Dec 03, 2007 at 09:47:41PM +, [EMAIL PROTECTED] wrote: > > > I think that the number of real-world apps in this class is perhaps > > not large, or there would be more hybrid code. > > Ah, bu

Re: [Beowulf] Using Autoparallel compilers or Multi-Threaded libraries with MPI

2007-12-03 Thread Greg Lindahl
On Mon, Dec 03, 2007 at 09:47:41PM +, [EMAIL PROTECTED] wrote: > I think that the number of real-world apps in this class is perhaps > not large, or there would be more hybrid code. Ah, but you've missed the random element here: People start writing hybrid code before they have any proof that

Re: [Beowulf] Using Autoparallel compilers or Multi-Threaded libraries with MPI

2007-12-03 Thread richard . walsh
-- Original message -- From: Håkon Bugge <[EMAIL PROTECTED]> > I have a slightly different view. Hybrid > programming is used for performance reasons, but > only in cases where parallelization (to the same > level) is impossible/impractical using the pure > MPI mode,

Re: [Beowulf] Using Autoparallel compilers or Multi-Threaded libraries with MPI

2007-12-03 Thread Greg Lindahl
On Mon, Dec 03, 2007 at 10:11:51AM +0100, H?kon Bugge wrote: > But > there are cases where you cannot; a) the > "decomposition parallel efficiency" is not good > enough or b) the processes need a huge (shared) table. You can accomplish (b) using a mmaped file, which is much easier than hybrid

Re: [Beowulf] Recommended paper for parallel sorting?

2007-12-03 Thread Robert G. Brown
On Mon, 3 Dec 2007, Peter St. John wrote: (re Ian Foster, *Designing and Building Parallel Programs *online as below or Addison Wesley): I did that search and right the top was this link, which looks like homebase for the original material: http://www-unix.mcs.anl.gov/dbpp/ Very cool, thanks RG

Re: [Beowulf] Recommended paper for parallel sorting?

2007-12-03 Thread Peter St. John
(re Ian Foster, *Designing and Building Parallel Programs *online as below or Addison Wesley): I did that search and right the top was this link, which looks like homebase for the original material: http://www-unix.mcs.anl.gov/dbpp/ Very cool, thanks RGB for what looks like toothsome book. Peter

Re: [Beowulf] Recommended paper for parallel sorting?

2007-12-03 Thread Robert G. Brown
On Sat, 1 Dec 2007, Nelson Castillo wrote: Hi. Could you please recommend a paper for reading? I'd like to know about parallel sorting algorithms for this architecture. You might check out Ian Foster's free online book on parallel algorithms. It is worth buying if you're going to be doing a

Re: [Beowulf] Using Autoparallel compilers or Multi-Threaded libraries with MPI

2007-12-03 Thread Håkon Bugge
At Sat, 1 Dec 2007 15:15:31,Greg Lindahl <[EMAIL PROTECTED]> wrote: > The SPEC HPG (High Performance Group) is having discussions about using > a hybrid of MPI and thread-level parallelism on the SPEC MPI2007 > benchmark suite. I'd find it useful to debunk the notion that hybrid programming actu