[Patches] Expanded group memberships on boundaries of outgoing trusts (bugs #13299, #13300, #13307)

[Douglas Bagnall]

[re-sending this, which got rejected this morning for being too big.
 The maximum graph mentioned below is now at
 https://www.samba.org/~dbagnall/expanded-graph-memberships-maximum.png]


On 02/03/18 01:17, Stefan Metzmacher wrote:
> Hi Douglas,
> 
>>>>>> I'll aim this at the perf testing rig,
>>>>>
>>>>> The results are shown in the attached chart, which compares
>>>>> yesterday's version of the patchset with yesterday's origin/master
>>>>> over three runs.
>>>>>
>>>>> Adding large groups (i.e. adding a group with lots of members in a
>>>>> single SamDB.add_ldif() operation) is slower, as is populating an
>>>>> existing group using add_ldif. Other operations are the same speed or
>>>>> slightly faster.
>>>>>
>>>>> There is quite a bit of noise when testing with just 3 runs, but the
>>>>> consistency across the different tests suggests this is a real change.
>>>>
>>>> Thanks! I hope the new version doesn't have such an impact.
>>>>
>>>>> I will try again with thew current head of 
>>>>> https://git.samba.org/?p=metze/samba/wip.git;a=shortlog;h=refs/heads/master3-trusts-ok
>>>>
>>>> The one that I recently pushed should compile and work.
>>>
>>> We should have a graph for that shortly.
>>
>> This one is more accurate for two reasons: it is over 6 runs not 3,
>> and it turns out the earlier version had some failures due to memory
>> pressure so that the origin/master there had only one run.
>>
>> I would say all the variation in the +/- 5 percent range is noise, but
>> there is still some slowdown in adding links in a transaction. Though
>> much less than before (~17% vs ~70%).
> 
> Thanks!
> 
> I think this is still noise, if you look at:
> 

Yes, it is noisy but there is still some signal. Attached is a graph
of the median time (which I should make the default), and also the
maximum.

In all cases, the times for adding links in a transaction go up a
little bit.

I am not objecting to the patches, though. It is only a little change
and we can always look at optimising later.

Douglas

-------------- next part --------------
A non-text attachment was scrubbed...
Name: expanded-graph-memberships-median.png
Type: image/png
Size: 215950 bytes
Desc: not available
URL: <http://lists.samba.org/pipermail/samba-technical/attachments/20180302/dad97733/expanded-graph-memberships-median-0001.png>