[OMPI devel] Option to switch from shmem to kmem module

2016-07-13 Thread Abhishek Joshi
Hi, Is there any option in mpirun which enables us to switch dynamically from shmem mode to knem/xpmem mode beyond a specifiable message size? This is because, according to my tests, knem performs better than shmem only at large message sizes. -- Abhishek

[OMPI devel] Use non-cpu frequency for timers

2016-05-20 Thread Abhishek Joshi
Hi, In amd64, we have rdtsc instruction which uses a timer updated at cpu frequency. The frequency is given by variable, opal_timer_linux_freq which is the cpu frequency. Consider the case where a timer updated at non-cpu frequency is to be used. Question: In this case, how do we specify the fr

[OMPI devel] Opal get cycles for ARM

2016-05-05 Thread Abhishek Joshi
Hi, I came across this patch in OMPI opal. https://www.open-mpi.org/community/lists/devel/2010/12/8819.php I am looking to add similar support for armv8-A but I have a small query regarding the implementation of *opal_sys_timer_get_cycles *for AMRv7-A. It uses the Linux *times *function which ret