On Thursday July 31, david@xxxxxxxxxxxx wrote: > aristizb@xxxxxxxxxxx wrote: > > Hi, > > > > I am currently working with a software Linux RAID1, with external bitmap > > and no write-behind option. Does the RAID controller keep the write > > order fidelity?. md/RAID1 provides the same guarantees as the underlying device, which usually isn't much of a guarantee. > > > > If an application writes some blocks on the RAID device in a particular > > order, can I ensure that these blocks will be written to the devices > > conforming the RAID on the same order, or at least on the main disk? > > (disk 0 on the RAID). > > I suspect you need to do some research on 'barriers'. > > I think the answer at present is 'no'. > > Hence messages like: > Filesystem "md0": Disabling barriers, not supported by the underlying device A strange message to get as md/RAID1 *does* support barriers when all the underlying devices do (since the mid-teens of 2.6 I think). NeilBrown -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
