RDO packstack very slow write on cinder volumes
I have an RDO packstack Newton setup with 1 controller node and 2 compute nodes, all on VMs run by KVM.
The cinder volume service is on the controller node as well. It's LVM accessed with ISCSI.
The write speed on a volume attached to an instance is extremely low, ~5MB/s
# dd if=/dev/zero of=baloon bs=1048576 count=200 oflag=dsync
200+0 records in
200+0 records out
209715200 bytes (210 MB) copied, 39.5572 s, 5.3 MB/s
The network speed between compute and storage(controller) nodes is 100MB/s
Any troubleshooting and tuning tips are appreciated.
Thanks.