I don't know the answer to your question, but this is certainly a very
interesting experiment.

Are you doing "different or same" comparison or do you have some sense of
how different the memory dumps are? Are we talking a few bytes or large
swaths of memory?

On Tue, Jan 10, 2012 at 11:10 AM, Addison Mayberry <[email protected]>wrote:

> Greetings,
> I am trying do some detailed performance tests, and to get more consistent
> data I have been trying to weed out issues that cause variation in my
> results on repeated executions of the same program from the same image
> checkpoint. To that end I started doing some analysis on the following two
> lines of code being executed in the simulator:
>
>    ptlcall_checkpoint_and_**shutdown("connection-made");
>    ptlcall_single_flush("-run");
>
> After which my benchmark code begins to run. I added code in PTLSim to do
> a dump of simulated physical memory when it receives the "-run"
> instruction, and comparing these dumps across multiple runs I found that
> they were different.
>
> I was aware that MARSS is not guaranteed (or expected) to have
> deterministic performance, but I was surprised that there would be
> variations in the execution over such a small period of time - between
> loading the checkpoint and then dropping into simulation. Does anyone have
> any thoughts on what might be causing the differences in memory state, and
> what I might be able to do to keep that from happening and make my tests
> more repeatable? Thanks for any insight.
> Sincerely,
> Addison
>
> ______________________________**_________________
> http://www.marss86.org
> Marss86-Devel mailing list
> [email protected].**edu <[email protected]>
> https://www.cs.binghamton.edu/**mailman/listinfo/marss86-devel<https://www.cs.binghamton.edu/mailman/listinfo/marss86-devel>
>
_______________________________________________
http://www.marss86.org
Marss86-Devel mailing list
[email protected]
https://www.cs.binghamton.edu/mailman/listinfo/marss86-devel

Reply via email to