Changes between Version 21 and Version 22 of Public/ParaStationMPI

Timestamp:

Jul 23, 2020, 11:11:32 AM (4 years ago)

Author:

Carsten Clauß

Comment:

—

Public/ParaStationMPI

@@ -40 +40 @@
 For using this feature, the following environment variables must be set:
 {{{
-- PSP_MSA_AWARENESS=1      # Generally activate the consideration of modular topologies (NOT enabled by default)
-- PSP_MSA_MODULE_ID=xyz    # Pass the respective Module ID (Integer) explicitly to the processes (NOT set automatically)
-}}}
-
-**Attention:** Please note that the environment variable for the respective Module ID (`PSP_MSA_MODULE_ID`) is currently ''not'' set automatically!
-This means that the user has to set and pass this variable explicitly, for example, via a bash script:
+- PSP_MSA_AWARENESS=1 # Generally activate the consideration of modular topologies (NOT enabled by default)
+- PSP_MSA_AWARE_COLLOPS=0|1|2 # Select the feature level:
+   0: Disable MSA awareness for collective MPI operations
+   1: Enable MSA awareness for collective MPI operations (default if PSP_MSA_AWARENESS=1 is set)
+   2: Apply MSA awareness recursively in multi-level topologies (set PSP_SMP_AWARENESS=1 in addition)
+}}}
+In the recursive application of MSA awareness (`PSP_MSA_AWARE_COLLOPS=2`), a distinction is first made between inter- and intra-**module** communication and then, in a second step, likewise between inter- and intra-**node** communication within the modules if `PSP_SMP_AWARENESS=1` is set in addition. (Please note that a meaningful usage of `PSP_MSA_AWARE_COLLOPS=2` requires `psmpi-5.4.5` or higher.)
+
+
+=== Usage with Older Versions ===
+
+For psmpi versions ''before'' 5.4.6, the Module IDs (`PSP_MSA_MODULE_ID`) were not set automatically!
+This means that the user had to set and pass this variable explicitly, for example, via a bash script:
 {{{
 #!/bin/bash
@@ -66 +73 @@
 }}}
 
-In addition, the following variable can be used to influence the behavior of the MSA awareness for the collective operations:
-{{{
-- PSP_MSA_AWARE_COLLOPS=0|1|2
-   0: Disable MSA awareness for collective MPI operations
-   1: Enable MSA awareness for collective MPI operations (default if PSP_MSA_AWARENESS=1 is set)
-   2: Apply MSA awareness recursively in multi-level topologies (set PSP_SMP_AWARENESS=1 in addition)
-}}}
-In the recursive application of MSA awareness (`PSP_MSA_AWARE_COLLOPS=2`), a distinction is first made between inter- and intra-**module** communication and then, in a second step, likewise between inter- and intra-**node** communication within the modules if `PSP_SMP_AWARENESS=1` is set in addition.
-
+However, since the current versions of psmpi (5.4.6), the Module ID is set automatically, which means that you can omit all the script stuff above.
+
+{{{#!comment
 **Attention:** Please note that a meaningful usage of `PSP_MSA_AWARE_COLLOPS=2` requires `psmpi-5.4.5` or higher.
 Currently (effective April 2020), this means that !ParaStation MPI has to be loaded on the DEEP-EST system as a module of the devel-stage:
@@ -84 +85 @@
 module load Intel
 module load ParaStationMPI
+}}}
 }}}