On Mon, Aug 29, 2022 at 10:26:20AM +0800, Wang Yugui wrote: > Hi, > > I saw some info about hybird xfs wih ssd/hdd by realtime subvol. > > Hybrid XFS—Using SSDs to Supercharge HDDs at Facebook > https://www.usenix.org/conference/srecon19asia/presentation/shamasunder .... > Is there any tool/kernel option/kernel patch to control the data to save > into normal vol or realtime subvol firstly? FB were running a modified kernel that selected the rt dev based on the initial allocation size. Behaviour for them was predictable because they also controlled the application that was storing the data. See: https://lore.kernel.org/linux-xfs/20171128215527.2510350-1-rwareing@xxxxxx/ -Dave. -- Dave Chinner david@xxxxxxxxxxxxx
