On Thu, Jan 23, 2025 at 11:11:13AM -0600, Vinay Banakar wrote: > Another option would be to modify shrink_folio_list() to force batch > flushes for up to N pages (512) at a time, rather than relying on > callers to do the batching via folio_list. If you really want to improve performance, consider converting shrink_folio_list() to take a folio_batch. I did this for page freeing: https://lore.kernel.org/all/20240227174254.710559-1-willy@xxxxxxxxxxxxx/ and we did in fact see a regression (due to shrinking the batch size from 32 to 15). We then increased the batch size from 15 to 31 and saw a 12.5% performance improvement on the page_fault2 benchmark over the original batch size of 32. Commit 9cecde80aae0 and https://lore.kernel.org/oe-lkp/202403151058.7048f6a8-oliver.sang@xxxxxxxxx/ have some more details. I think you should be able to see a noticable improvement by going from a list with 512 entries on it to a batch of 31 entries.
