Hello, I was thinking how to best address the performance regression coming from NFS write congestion. After considering various options and concerns raised in the previous discussion, I've got an idea for a simple option that could help to keep the server more busy - just mimick what block devices do and block the flush worker waiting for congestion to resolve instead of aborting the writeback. And it actually helps enough that I don't think more complex solutions are warranted at this point. This patch series has two preparatory cleanups and then a patch implementing this idea. Honza
