bb00453e58
Current code is associating a transaction id with each device and if pool transaction id is greater that value, then current code assumes that device is there in pool. Transaction id of pool is a mechanism so that during device creation and removal one can define a transaction and during startup figure out if transaction was complete or not. I think we are using transaction id throughout the code little inappropriately. For example, if a device is being deleted, it is possible that we deleted the device from pool but before we could delete metafile docker crashed. When docker comes back it will think that device is in the pool (due to device transaction id being less than pool transaction id) but device is not in the pool. Similary, it could happen that some data in the pool is corrupted and during pool repair some devices are lost (without docker knowing about it). In that case tool pool transaction id will be higher than device transaction id and there are no guaratees that device is actually in the pool. So move away from this model where we think that a device is in pool if pool transaction id is greater than device transaction Id. Per device transaction Id just says that after device creation this should be pool's transaction Id and nothing more. Transaction id is per pool property (as opposed to per device property) and will be used internally to figure out if last transaction was complete or not and recover from failure during docker startup. If for some reason metafile is present but device is not in pool, then device activation will fail later. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> |
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| .. | ||
| aufs | ||
| btrfs | ||
| devmapper | ||
| graphtest | ||
| overlayfs | ||
| vfs | ||
| driver.go | ||
| fsdiff.go | ||