Hi I uploaded my test clustered snapshots to http://people.redhat.com/mpatocka/patches/kernel/clustered-snapshots-preview/ My patches take different approach from Jon's patches. My patches basically replace down_write(&s->lock) and up_write(&s->lock) with clusterized locking. If there are pending exceptions, the cluster lock must be held while the local lock is unlocked. The cluster lock is droppen when all pending exceptions are reallocated and the local lock is dropped. The patches are based on my & Mike's merging. These patches are less invasive than Jon's, they area small, they don't change so much logic and most importantly, they leave merging as it is. Note that it was never tried in a cluster because I don't have a cluster!! So there may be a silly bug that makes it not work at all. The purpose of the patches is to show different simpler approach to clustering. You should test it and debug it. TODO: - implement lock caching (Jon's task for his dm-lock module) - once we implement it, we can implement selective re-read --- i.e. don't reread the exceptions if the cluster lock was not taken by any other node - in a few cases we could optimize it to use readlock or only local lock - implemented cluster merging Mikulas -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
