I've updated both the DM and LVM2 snapshot-merge patches to the latest upstream Linux and LVM2. All patches (both Linux and LVM2) have been tested to pass the LVM2 testsuite. There is more work to be done on these patches but I wanted to make others aware of them sooner rather than later. The basis for the DM snapshot-merge patches is Linux 2.6.31-rc8 + the remaining DM fixes that Alasdair should be pushing to Linus this week: http://people.redhat.com/msnitzer/patches/dm-2.6.31-rc-fixes/ The DM snapshot-merge patches are here: http://people.redhat.com/msnitzer/patches/snapshot-merge/kernel/2.6.31/ The LVM2 snapshot-merge patches are here: http://people.redhat.com/msnitzer/patches/snapshot-merge/lvm2/LVM2-2.02.52-cvs/ I threw some real work at snapshot-merge by taking a snap _before_ formatting a 100G LV with ext3. Then merged all the exceptions. One observation is that the merge process is _quite_ slow in comparison to how long it took to format the LV (with associated snapshot exception copy-out). Will need to look at this further shortly... it's likely a function of using minimal system resources during the merge via kcopyd; whereas the ext3 format puts excessive pressure on the system's page cache to queue work for mkfs's immediate writeback. # lvcreate -n testlv -L 100G test # lvcreate -n testlv_snap -s -L 20G test/testlv # lvs LV VG Attr LSize Origin Snap% Move Log Copy% Convert testlv test owi-a- 100.00G testlv_snap test swi-a- 20.00G testlv 0.00 # mkfs.ext3 /dev/test/testlv # lvs LV VG Attr LSize Origin Snap% Move Log Copy% Convert testlv test owi-a- 100.00G testlv_snap test swi-a- 20.00G testlv 8.52 # lvconvert -M test/testlv_snap Merging of volume testlv_snap started. testlv: Merged: 8.5% testlv: Merged: 8.4% testlv: Merged: 8.4% testlv: Merged: 8.3% ... testlv: Merged: 7.2% ... testlv: Merged: 0.0% testlv: Merged: 0.0% testlv: Merged: 0.0% Merge into logical volume testlv finished. Logical volume "snapshot1" successfully removed -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
