Documentation

MALP in two minutes

Launch your app in MPMD with the analyzer:

mpirun -np 64 malp APP [APP_ARGS] : -np 16 malp_an

Observe how the application is ‘wrapped’ with the malp command and how we concurrently launch the analysis server malp_an. You can  change the analysis ratio, launching less analysis process than instrumented processes. MALP also come with a wrapper for this syntax, the malpl command.

Console output when launching MALP on NPB
Console output when launching MALP on NPB

If the instrumentation succeeded you should see this header, the list before the header will give you the detected partitions (MALP can instrument several applications at once, to do so reproduce the MPMD pattern with a single analysis partition).

When the program ends, it will generate an output JSON file called, MALP_trace.json, this file contain the result of the performance analysis.

Launch the analysis server:

MALP_PORT=8080 malp_server

This command will launch the Node.JS server which is a place where you can manage and upload you performance traces. Note that you can launch this interface to consult previously generated profiles.

Output when launching the malp_server
Output when launching the malp_server

Open your default browser to this page:

x-www-browser http://127.0.0.1:8080
Main page of the MALP Web-Based interface.
Main page of the MALP Web-Based interface.

Go to the performance catalog and upload the MALP_trace.json file generated during step 1:

Empty performance catalog, only waiting for you to upload your first trace !
Empty performance catalog, only waiting for you to upload your first trace !
Click on the "Upload Trace" button and select the profile file.
Click on the “Upload Trace” button and select the profile file.
Fill in run meta-data and upload.
Fill in run meta-data and upload.
Your performance trace is now present in the performance catalog, you can use it later on.
Your performance trace is now present in the performance catalog, you can use it later on.

After these steps, you can explore your performance trace using the various buttons at the top of the page. Note that if you ever want to load another trace, this has to be done in the Performance Catalog, doing so will update all the other modules. Eventually, note that the file which is currently loaded is displayed at the top of the page for convenience.