What is a bottleneck?

Software-based VM-centric and flash-friendly VM storage + free version

Moderators: anton (staff), art (staff), Max (staff), Anatoly (staff)

Post Reply
Davis
Posts: 24
Joined: Tue Jan 23, 2018 10:12 am

Mon Sep 10, 2018 11:24 am

Hi all,

I have a small Hyper-V 2012 R2 hyperconvergent cluster with Starwind Virtual SAN Free storage.
Briefly about each node config:
2xXeon 6cores 2.1GHz
32GB RAM
2x1Gb builtin NICs
2x1Gb addon NICs
2x1TB SATA 7200 in mirror volume via Storage Spaces for data
1GB L1 cache in StarWind flat fixed size(300GB) HA device, placed on this mirror volume.
Jumbo on.
Two builtin NICs used for cluster and clients, one addon NIC - iSCSI and SW sync, second - SW sync. SW heartbeat - on all four NICs.

It works. I have several VM running on it. Of course storage subsystem is expectedly slow.

I'm wondering - if I want to speed up the storage, then what is the best way to spend money: to replace an addon NIC with 10Gb one or replace a mirror with single enterprise SSD?

Currently storage shows such results(diskspd -c500M -w100 -t1 -o1 -b64K -Su ...):
1. SS Mirror drive itself: 110 MB/sec
2. C:\ClusterStorage created using SW HA device: 25 MB/sec
3. Inside of one of 2012 R2 VM: 20 MB/sec

My opinion: replacing NIC with 10Gb will significantly rise 2) and 3) speeds.
Am I right?
How much can acceleration be?
Boris (staff)
Staff
Posts: 805
Joined: Fri Jul 28, 2017 8:18 am

Mon Sep 10, 2018 7:37 pm

Davis,

I believe 10 Gbit card would be a good investment. Replace your 2x1Gbps sync connections with at least one 10Gbps NIC and you will be good to go.
Davis
Posts: 24
Joined: Tue Jan 23, 2018 10:12 am

Tue Sep 11, 2018 6:52 am

Thank you!
Michael (staff)
Staff
Posts: 317
Joined: Thu Jul 21, 2016 10:16 am

Mon Oct 08, 2018 8:36 am

Thank you as well!
Davis
Posts: 24
Joined: Tue Jan 23, 2018 10:12 am

Wed Jan 23, 2019 12:22 pm

Just for Info.
I've upgraded addon NICs to Mellanox ConnectX-3 Pro dual ports 10Gb cards on both nodes.
So now both Sync channels are 10Gb/sec.

Transfer rate for ClusterStorage raised to 53MB/sec
Speed inside VM have not changed significantly: 20-35MB/sec. From test to test.

Test with RAM drive over 10Gb iSCSI ( client->iscsi->10Gb->RAM drive) shows 330 MB/sec for single thread or full saturated 1150MB/sec for 8 thread
Boris (staff)
Staff
Posts: 805
Joined: Fri Jul 28, 2017 8:18 am

Wed Jan 23, 2019 3:40 pm

Speed inside VM have not changed significantly: 20-35MB/sec. From test to test.
Make sure you use fixed disks for your VMs, but not dynamic ones. With dynamic disks performance is far from the best one.
Davis
Posts: 24
Joined: Tue Jan 23, 2018 10:12 am

Wed Jan 23, 2019 4:06 pm

fixed, sure
Boris (staff)
Staff
Posts: 805
Joined: Fri Jul 28, 2017 8:18 am

Thu Jan 24, 2019 4:12 pm

Can you run the test on several VMs simultaneously? What is the summed up result?
Post Reply