On Thu, Mar 07, 2024 at 08:53:43AM -0500, Phillip Susi wrote: > I have noticed that whenever you suspend to ram or shutdown the system, > runtime pm suspended disks are woken up only to be spun right back down > again. This is because the kernel syncs all filesystems, and they issue > a cache flush. Since the disk is suspended however, there is nothing in > the cache to flush, so this is wasteful. > > Should this be solved in the filesystems, or the block layer? > > I first started trying to fix this in ext4, but now I am thinking this > is more of a generic issue that should be solved in the block layer. I > am thinking that the block layer could keep a dirty flag that is set by > any write request, and cleared by a flush, or when the disk is > suspended. As long as the dirty flag is not set, any flush requests can > just be discarded. > > Thoughts? How do other filesystems behave? Is this a problem just on specific filesystems? -Dave. -- Dave Chinner david@xxxxxxxxxxxxx
