[ovirt-users] VMs seems to be slow, while snapshot delete is happening

Hi All, I have created a VM with 60GB of disk space. I have started I/O inside the VM, after sometime when the disk was 4GB full, I took a snapshot of the disk from UI. I/O kept continuing and the new image file ( overlay file ) was 15GB in size. Now I deleted the snapshot. I think this would initiate block-merges. During this time, my I/O was were slower, till the snapshot delete is completed. Its not very slow, but slow. Is this a known behavior ? Advance thanks, Satheesaran S