On Wed, Aug 11, 2021 at 03:46:47AM +0100, Matthew Wilcox (Oracle) wrote: > For O_SYNC writes, if the filesystem has already allocated blocks for > the range, we can avoid marking the page as dirty and skip straight to > marking the page as writeback. So this just optimizes O_SYNC overwrites. How common are those for bufered I/O? I know databases use them a lot with direct I/O, but for buffere I/O this seems like an odd I/O pattern.
