John R Pierce wrote: > Mark Caudill wrote: >> Wait, just to be clear, are you saying that all use of LVM is a bad idea >> unless on hardware RAID? That's bad it if it's true since it seems to me >> that most modern distros like to use LVM by default. Am I missing something? >> > > if LVM is ignoring write barriers, its not a good idea on hardware raid, > either, at least not for applications that rely on committed writes, > like transactional databases. > Write barriers are for the case of getting a data guarantee with hard disks connected via sata/scsi that have their write caches enabled. Hardware raid + bbu cache change that game. LVM on hardware raid is safe due to the bbu cache (with write caches on connected hard drives set to off)