cinder block slow performance [closed]
Hello all,
Setup information:
Openstack Version: Newton
1 KVM Controller on Server 1
1 KVM Cinder on Server 2. Server 2 has attached SSD of 120G as a block device(haven't created any file-system on SSD )
1 Compute node, Server 3
I have a pass-through configuration for SSD on Cinder VM and I can see the drive mounted as /dev/vda I have created an OpenStack instance on Compute node, let's call it VM-1. A Cinder volume is being attached to it and its mounted as /dev/vdb on VM-1.
Issue: I am seeing a very low disk Read/writes numbers for the mounted volume on VM-1.
Troubleshooting and HDPARM numbers till now:
1) SERVER 2(host for Cinder VM):
hdparm -Tt /dev/sda (SSD mount point)
Timing cached reads: 14808 MB in
2.00 seconds = 7411.80 MB/sec
Timing buffered disk reads: 1208 MB in 3.00 seconds = 402.03 MB/sec
2) CINDER VM (on Server 2):
hdparm -t -direct /dev/vda
/dev/vda:
Timing cached reads: 14136 MB in 1.98 seconds = 7125.59 MB/sec
Timing buffered disk reads: 1196 MB in 3.00 seconds = 398.15 MB/sec
3) VM-1 (on Server 3):
hdparm -t --direct **/dev/vdb**
/dev/vda:
Timing O_DIRECT disk reads: 208 MB in 3.01 seconds = 69.10 MB/sec
You can see there is a huge difference in disk reads in #2 and #3. Both the servers (server 2 and 3) are connected by 1000Mbps link. But, I found something strange when I checked network interfaces for the VM-1 on compute node(server 3).
ETHTOOL for eth0 (physical interface on Server3)
...
Advertised pause frame use: Symmetric
Advertised auto-negotiation: Yes
*Speed: 1000Mb/s*
Duplex: Full
Port: Twisted Pair
...
ETHTOOL for TAP interface attached to VM-1:
...
Supports auto-negotiation: No
Advertised link modes: Not reported
Advertised pause frame use: No
Advertised auto-negotiation: No
**Speed: 10Mb/s**
Duplex: Full
Port: Twisted Pair
PHYAD: 0
Transceiver: internal
Auto-negotiation: off
...
Interface speeds show huge difference here as well. Please suggest if there is any way I can change this speed on tap interface. Is there any configuration file or anything where I can specify this?
Looking forward for expert advice.
EDIT 1: Corrected VM-1's device name for Cinder Volume.
TIA