[Gems-users] Pading to get rid of false sharing

[Ricardo Quislant del Barrio <quislant@xxxxxxxxx>]

Hi Luke,
You told me in other message how to pad data structures so as to avoid 
false sharing:
   "... to avoid false sharing between threads. This is done by running
   the smallest imperfect signature (e.g., 64 bit signatures) and working
   backwards from the stall stats by PC to see where the stalls occur in
   the code."

Why should I start by running the smallest imperfect signature?
If I try with the Perfect Signature I'll get stalls due to false sharing
and due to actual conflicts and with Imperfect Signature I'll get those 
conflicts
and false positives too. So, why should I start by running the smallest 
imperfect
signature and not the Perfect one?

Another question is: When you say "stall stats by PC" do you mean "xact 
Nacks by PC"?
Thanks,
Ricardo