Re: [PATCH net-next] sctp: support per-association stats via a new SCTP_GET_ASSOC_STATS call

On 10/30/12 at 10:25am, Vlad Yasevich wrote:

Can you give me some reasons why you prefer 0?

0 seems a bit strange to me.  if someone was to construct a
histogram of values, they would start with some initial value, then
see 0s if there is no change, a spike for large rto, and if the
spike is corrected, it would drop to 0 indicating no change...
Seems odd.

I would rather see what the current observed max rto is for an
application polling period.  Then a histogram can be correctly
constructed.

0 would indicate that the rto has not been recalculated since
the last read and the app can decideitself whether to ignore
that read, replace it with rto_min or use the last known good
rto_max value.

Obviously this would mean that the patch needs to be changed
so it updates the max observed rto after applying rto_min in
sctp_transport_update_rto().

I'm perfectly fine with using rto_min as well though, we just lose
a bit of information that may be helpful to some users.