Incremental provision is slow on ContentTypeFieldLinkDefinitions

[SubPointSupport]

As per @andreasblueher feedback, ContentTypeFieldLinkDefinitions seems to have performance issues with incremental provision. This concert was also raise by a few other people.

Initially, it might have to do with:

• SSOM way content types resolved and constantly updated over evert link
• Slow content type resolution for every link (if there are a lot of content types over there)
• Slow content type update over a large amount of content (.Update(true) would be slow)

The issue extremely hard to catch due to many variables involved. Internal metrics over provision operation is a must: Introduce model provision metrics - time, queries, traffic #1007

Another level to test is a large amount of content, in particular, tons of webs/list where the content type is used.

Finally, incremental provision need to be enhanced so that either one of these is true:

• no artefact lookup would be required for child artifacts
• incremental provision would pre-calculate and cut nodes which don't need to be provisioned

That increases complexity of the issue as incremental provision needs to be regressed and properly covered with regression testing once a better diff calculations are introduced.

https://github.com/SubPointSolutions/spmeta2/issues/553#issuecomment-314761611

[andreasblueher]

Just some more information from my side here. The ContentTypes I used which appeared to have no benefit from incremental updates contained about 50 columns. There are only 5 custom ContentTypes in this web and the 50 column CT is only used on one list.

[SubPointSupport]

Makes sense, thanks @andreasblueher