On Wed, Aug 17, 2016 at 03:42:34PM +0800, Aaron Lu wrote:
> On 08/17/2016 03:35 PM, Xin Long wrote:
> >> include/net/sctp/structs.h | 3 +++
> >> 1 file changed, 3 insertions(+)
> >>
> >> diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
> >> index d8e464aacb20..932f2780d3a4 100644
> >> --- a/include/net/sctp/structs.h
> >> +++ b/include/net/sctp/structs.h
> >> @@ -602,6 +602,9 @@ struct sctp_chunk {
> >> /* This needs to be recoverable for SCTP_SEND_FAILED events. */
> >> struct sctp_sndrcvinfo sinfo;
> >>
> >> + unsigned long prsctp_param;
> >> + int sent_count;
> >> +
> >> /* Which association does this belong to? */
> >> struct sctp_association *asoc;
> >>
> >> --
> >> 2.5.5
> >>
> >> Then the performance dropped to the same as the bisected commit
> >> a6c2f792873a:
> >> $ cat 4.7.0-rc6-01198-g98dd2532b14e/0/netperf.json
> >> {
> >> "netperf.Throughput_Mbps": [
> >> 754.494375
> >> ]
> >> }
> >>
> >> I think this agrees with the perf data in that the newly added function
> >> doesn't show up in the perf-profile but still, the performance drops.
> >> So the only possible reason is the newly added fields to the sctp_chunk
> >> structure.
> >>
> >> Is this expected?
> > interesting , you didn't include the modification of the functions
> > parts, right ?
>
> Yes.
>
> > you mean only this two line:
> >> + unsigned long prsctp_param;
> >> + int sent_count;ca;
> >
> > caused the performance issue ?
>
> Right.
Note the test is done on my own Sandybridge desktop, I'll queue a job to
run on the Ivybridge test box now.
