Re: [OMPI devel] Notes from mem hooks call today

On May 28, 2008, at 5:09 PM, Roland Dreier wrote: I think Patrick's point is that it's not too much more expensive to do the syscall on Linux vs just doing the cache lookup, particularly in the context of a long message. And it means that upper layer protocols like MPI don't have to deal

Re: [OMPI devel] Notes from mem hooks call today

> I think Patrick's point is that it's not too much more expensive to do the > syscall on Linux vs just doing the cache lookup, particularly in the > context of a long message. And it means that upper layer protocols like > MPI don't have to deal with caches (and since MPI implementors

Re: [OMPI devel] Notes from mem hooks call today

On Wed, 28 May 2008, Roland Dreier wrote: >- gleb asks: don't we want to avoid the system call when possible? >- patrick: a single syscall can be/is cheaper than a reg cache > lookup in user space This doesn't really make sense -- syscall + cache lookup in kernel is "obviously"

Re: [OMPI devel] RFC: Linuxes shipping libibverbs

On May 28, 2008, at 8:02 AM, Jeff Squyres wrote: Note that the two /sys checks may be redundant; I'm not entirely sure how the two files relate to each other. libibverbs will complain about the first if it is not present; the second is used to indicate that the kernel drivers are loaded. I

Re: [OMPI devel] Notes from mem hooks call today

>- gleb asks: don't we want to avoid the system call when possible? >- patrick: a single syscall can be/is cheaper than a reg cache > lookup in user space This doesn't really make sense -- syscall + cache lookup in kernel is "obviously" more expensive than cache lookup in

Re: [OMPI devel] Open MPI session directory location

After chatting with Jeff to better understand the ompi_info issue, I consolidated all the ORTE-level MCA param registrations that are relevant to users and had ompi_info call it. You will now see them displayed by ompi_info. Ralph On 5/27/08 1:57 PM, "Jeff Squyres" wrote:

[OMPI devel] SM BTL NUMA awareness patches

Hi, Attached two patches implement NUMA awareness in SM BTL. The first one adds two new functions to maffinity framework required by the second patch. The functions are: opal_maffinity_base_node_name_to_id() - gets a string that represents a memory node

Re: [OMPI devel] mpirun hangs

That fixed it, thanks. I wonder if this is the same problem I'm seeing for 1.2.x? Greg On May 27, 2008, at 10:34 PM, Ralph Castain wrote: Aha! This is a problem that continues to bite us - it relates to the pty problem in Mac OSX. Been a ton of chatter about this, but Mac doesn't seem

Re: [OMPI devel] RFC: Linuxes shipping libibverbs

Ok. With lots more off-list discussion, how's this pseudocode for a proposal: # Main assumption: if the kernel drivers are loaded, the user wants RDMA # hardware support in OMPI. $sysfsdir = ibv_get_sysfs_path(); # Avoid printing "Fatal: couldn't read uverbs ABI version" message.