Github user pvillard31 commented on the issue:
https://github.com/apache/nifi/pull/2475
Few suggestions regarding existing processors: ExtractText and ReplaceText
can also be CPU intensive when using some tricky regular expressions. Same goes
for grok processors as well as TransformXML (depends of the XSLT). It's not
true in most cases but it can be in some situations. Will try to continue the
review early next week.---
