On Thu, Jul 13, 2017 at 8:52 PM, Qu Wenruo <quwenruo.btrfs@xxxxxxx> wrote: > > Thanks for mentioning the underlying storage. > SSD makes FUA overhead smaller, so with SSD the metadata CoW is less > obvious. Typically there are 2 or 3 superblocks. SSD mount option causes rotation of superblock updates. I wonder the effect this rotation would have on HDD performance rather than FUA causing all supers being updated. > Latency wise, the AUFS/Overlayfs seems to be the proble > > BTW, why not just ZFS-on-Linux? As ZFS also supports snapshot, maybe it will > has similar latency compared to btrfs. Maybe. But the volume management it's not as flexible as Btrfs. No shrink, no device removal, no migration to mixed block device sizes so consolidation of backing devices in cloud is a bigger hassle if you want to stay online during migrate. Not a big deal but they're useful features. -- Chris Murphy -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
