Degraded write performance on gluster involving RHHI/RHEV workloads

Issue

• The write performance of a VM (created with RHVM) with virtual disks which are actually block devices located on the gluster volume, was acutely low. FIO was executed from this virtual disk which was attached to the VM via virtio/virtio-scsi drivers and reported close to 1K fops (gluster was on NVME disks)