Changes between Version 5 and Version 6 of WorkingGroups/HPC

Timestamp:

2014-11-05T22:49:20+01:00 (10 years ago)

Author:

smasson

Comment:

--

WorkingGroups/HPC

@@ -30 +30 @@
 
 == Some ideas...:[[BR]] ==
-A strong improvement of NEMO scalability is needed to be able to take advantage of the new machines. This means a deep review/rewrite of NEMO code at some point in the futur (beyond 5 years). At the same time, we already know that CMIP7 won't use an ocean model that has not been strongly tested and validated and will stick to a NEMO model close to the existing one. [[BR]]
+A strong improvement of NEMO scalability is needed to be able to take advantage of the new machines. This probably means a deep review/rewrite of NEMO code at some point in the futur (beyond 5 years from now?). At the same time, we already know that CMIP7 won't use an ocean model that has not been strongly tested and validated and will stick to a NEMO model not so far from the existing one. [[BR]]
 This means that we need to:
  1) keep improving the current structure of NEMO so it works quite efficiently for almost 10 more years (until the end of CMPI7). [[BR]]
- 2) start to work on a new structure that would be tested from year 5 and fully tested and validated for CMIP8 in about 10 years. [[BR]]
+ 2) start to work on a new structure that would fully tested and validated at least for CMIP8 in about 10 years. [[BR]]
 
-Based on this, we propose to divide the work according to 3 temporal window [[BR]]
+Based on this, we propose to divide the work according to 3 temporal windows [[BR]]
 
-'''0-3 years''': improvements with existing code: Do basic optimisation work: [[BR]]
- 1) reduce the number of communications: remove useless communications (a lot) [[BR]]
- 2) reduce the number of communications: do less and bigger communications (group communications, use large halo) [[BR]]
+'''0-3 years''': improvements with existing code: [[BR]]
+ 0) remove solvers (to be done in 3.7)
+ 1) reduce the number of communications: do less and bigger communications (group communications, use larger halo). main priority: communications in the time splitting. [[BR]]
+ 2) reduce the number of communications: remove useless communications (a lot) [[BR]]
  3) introduce asynchronous communications 
  3) check code vectorization (SIMD instructions) [[BR]]
@@ -45 +46 @@
 '''0-5 years''': improvements through the introduction of OpenMP:  [[BR]]
  work initialed by CMCC. 
- "Basic" implementation such as tiling may be efficient with many cores processors? 
- test different way to find new sources of parallelism.
-OpenMP4, OpenACC?
+ implementation such as tiling may be efficient with many cores processors? review lbclnk to be able to deal with MPI and OpenMP
+ OpenMP along the vertical axis? Find a way to remove implicit schemes?  
+ test different way to find new sources of parallelism for example with the help of OpenMP4
+ test OpenACC (not that far from OpenMP)?
 
 '''beyond 5 years''': [[BR]]