or proxies - NERSC
or proxies - NERSC
or proxies - NERSC
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
Goal f<strong>or</strong> Programmers at All Levels !<br />
(NNSA Exascale Roadmapping W<strong>or</strong>kshop in SF, 2011) <br />
• Minimize the number of lines of code I have to change when <br />
we move to next version of a machine <br />
– Evidence that current abstrac2ons are broken are en2rely related to <br />
eff<strong>or</strong>t required to move to each new machine <br />
– Target is the FIRST DERIVATIVE of technology changes!!! <br />
• What is changing the fastest What do we want to make <br />
future programming models less sensi0ve to <br />
– Insensi2ve to # c<strong>or</strong>es (but unclear if as w<strong>or</strong>ried about # of nodes) <br />
– Less sensi2ve to sources of of non-‐unif<strong>or</strong>mity (execu2on rates and <br />
heterogeneous c<strong>or</strong>e types) <br />
– Mem<strong>or</strong>y capacity/compute ra2o (strong’ish’-‐scaling) <br />
– Data Movement Constraints <br />
• Increasingly distance-‐dependent cost of data movement <br />
• Topological constraints (node-‐scale & system-‐wide) <br />
• Expressed as NUMA domains (within node) <br />
-‐ 4 -‐ <br />
Slide from John Shalf
Change language