To quote the article:

"Wilcox said that much of the kernel's reclaim machinery may not be relevant anymore; it was designed in the days when filesystems were far less capable than they are now. Good filesystems now are already keeping all of their drives busy doing writeback; there is really little more that they can do if the memory-management code wants them to free specific pages. Perhaps the memory-management subsystem should simply stop requesting the reclaim of pages that reach the end of the least-recently-used (LRU) list, he suggested.

There is a possible way to test that idea, he said; perhaps filesystems should simply remove their implementation of the writepage() address-space operation "

Is this a good idea for Lustre? It's not clear - but let's see how it fares in Maloo at least.

https://lwn.net/Articles/893512/