lkml.org 
[lkml]   [2016]   [Aug]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [LKP] [lkp] [sctp] a6c2f79287: netperf.Throughput_Mbps -37.2% regression
From
Date
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.

\
 
 \ /
  Last update: 2016-09-17 09:57    [W:1.731 / U:0.184 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site