[ovirt-users] Poor performance of oVirt Export Domain

Hello I deployed a dedicated server (fs05.holding.com) on CentOS 7.5 and created a VDO volume on it. The local write test in the VDO volume on this server gives us an acceptable result # dd if=/dev/zero of=/mnt/vdo-vd1/nfs/testfile count=1000000 1000000+0 records in 1000000+0 records out 512000000 bytes (512 MB) copied, 6.26545 s, 81.7 MB/s The disk capacity of the VDO volume is connected to the oVirt 4.2.5 cluster as the Export Domain via NFS. I'm seeing a problem with the low performance of Export Domain. Snapshots of virtual machines are copied very slowly to the Export Domain, approximately 6-8 MB/s. At the same time, if I try to run a write test in an mounted NFS-directory on any of the oVit cluster hosts, I get about 50-70 MB/s. # dd if=/dev/zero of=/rhev/data-center/mnt/fs05.holding.com:_mnt_vdo-vd1_nfs_ovirt-vm-backup/testfile count=10000000 10000000+0 records in 10000000+0 records out 5120000000 bytes (5.1 GB) copied, 69.5506 s, 73.6 MB/s Help me understand the reason for the slow copying to Export Domain on oVirt.