Hi, I had noticed that deleting a large fully mapped thin device (> 10TB) on a pool with small block size could take couple of minutes, for it needs to traverse all the way down to the tree to decrement the reference count of all mapped blocks. Since deleting device needs to take "pmd->root_lock" write lock, I/O will hang since it also need to held this lock for finding block mapping, provisioning blocks, or breaking shared blocks. Some applications will treat the long I/O response time as I/O error and the service will become offline. I had traced the code and wished to find a way to release this lock every couple of seconds when deleting a large thin device. However, since I cannot figure out any elegant and formal way to do so. I am wondering if someone can shed some light on this problem. Is there any way I can pull this off nice and clean? Any help would be grateful. Thanks for your patience. Dennis -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
