From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andi Kleen <ak@linux.intel.com>
Subject: Re: [RFC PATCH 0/7] Share events between metrics
Date: Thu, 7 May 2020 14:46:52 -0700
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> > - without this change events within a metric may get scheduled
> >   together, after they may appear as part of a larger group and be
> >   multiplexed at different times, lowering accuracy - however, less
> >   multiplexing may compensate for this.
> 
> I agree the heuristic in this patch set is naive and would welcome to
> improve it from your toplev experience. I think this change is
> progress on TopDownL1 - would you agree?

TopdownL1 in non SMT mode should always fit. Inside a group
deduping always makes sense. 

The problem is SMT mode where it doesn't fit. toplev tries
to group each node and each level together.

> 
> I'm wondering if what is needed are flags to control behavior. For
> example, avoiding the use of groups altogether. For TopDownL1 I see.

Yes the current situation isn't great.

For Topdown your patch clearly is an improvement, I'm not sure
it's for everything though.

Probably the advanced heuristics are only useful for a few
formulas, most are very simple. So maybe it's ok. I guess
would need some testing over the existing formulas.


-Andi