Yellow Bricks

by Duncan Epping

benchmark

Where is the vSAN storage performance proactive test in vSphere 6.5 U1 patch 02?

· ·

I had some customers asking where the storage performance proactive test and the multicast proactive test was in the latest release of vSAN. In the past this is what the UI looked like when they would go to the Proactive Test section:

proactive test disappeared

But now it looks like this:

proactive test disappeared

What happened? Well, two tests have been removed. I guess most people will understand why the Multicast test has been removed, with the disappearance of Multicast in vSAN the test was not needed any longer. To be clear, if you are running vSAN in unicast mode the test will not show, if you are running in multicast mode however then of course the test will still be shown. But what about the Storage Performance Test?

We have noticed that most customers were using HCI Bench when doing benchmarks or using their own tooling (please don’t use legacy tools). Those who were using the proactive test often drew incorrect conclusions as it does not provide the flexibility a solution like HCI Bench offers. VMware felt that HCI Bench was a more suitable solution for doing benchmarks and this is definitely VMware’s recommended solution, as such the decision was made to focus on HCI Bench from a development perspective and deprecate the perf benchmark feature in the Proactive Tests section.

Benchmarking an HCI solution with legacy tools

· ·

I was driving back home from Germany on the autobahn this week when thinking about 5-6 conversations I have had the past couple of weeks about performance tests for HCI systems. (Hence the pic on the rightside being very appropriate ;-)) What stood out during these conversations is that many folks are repeating the tests they’ve once conducted on their legacy array and then compare the results 1:1 to their HCI system. Fairly often people even use a legacy tool like Atto disk benchmark. Atto is a great tool for testing the speed of your drive in your laptop, or maybe even a RAID configuration, but the name already more or less reveals its limitation: “disk benchmark”. It wasn’t designed to show the capabilities and strengths of a distributed / hyper-converged platform.

Now I am not trying to pick on Atto as similar problems exist with tools like IOMeter for instance. I see people doing a single VM IOMeter test with a single disk. In most hyper-converged offerings that doesn’t result in a spectacular outcome, why? Well simply because that is not what the solution is designed for. Sure, there are ways to demonstrate what your system is capable off with legacy tools, simply create multiple VMs with multiple disks. Or even with a single VM you can produce better results when picking the right policy as vSAN allows you to stripe data across 12 devices for instance (which can be across hosts, diskgroups etc). Without selecting the right policy or having multiple VMs, you may not be hitting the limits of your system, but simply the limits of your VM virtual disk controller, host disk controller, single device capabilities etc.

But there is even a better option, pick the right toolset and select the right workload(Surely only doing 4k blocks isn’t representative of your prod environment). VMware has developed a benchmarking solution that works with both traditional as well as with hyper-converged offerings called HCIBench. HCIBench can be downloaded for free, and used for free, through the VMware Flings website. Instead of that single VM single disk test, you will now be able to test many VMs with multiple disks to show how a scale-out storage system behaves. It will provide you great insights of the capabilities of your storage system, whether that is vSAN or any other HCI solution, or even a legacy storage system for that matter. Just like the world of storage has evolved, so has the world of benchmarking.

Cool tool: vBenchmark fling

· ·

Today I decided to start testing the vBenchmark fling. It sounded like a cool tool so I installed it in my lab. You can find the fling here for those wanting to test it themselves. So what doe the tool do? The VMware Labs website summarizes it in a good way:

Have you ever wondered how to quantify the benefits of virtualization to your management? If so, please consider using vBenchmark. vBenchmark measures the performance of a VMware virtualized infrastructure across three categories:

  • Efficiency: for example, how much physical RAM are you saving by using virtualization?
  • Operational Agility: for example, how much time do you take on average to provision a VM?
  • Quality of Service: for example, how much downtime do you avoid by using availability features?

vBenchmark provides a succinct set of metrics in these categories for your VMware virtualized private cloud. Additionally, if you choose to contribute your metrics to the community repository, vBenchmark also allows you to compare your metrics against those of comparable companies in your peer group. The data you submit is anonymized and encrypted for secure transmission.

The appliance can be deployed in a fairly simple way:

  • Download OVA –> unzip
  • Open vCenter client –> File –> Deploy OVF Template
  • Select the vBenchmark OVA as a source
  • Give it a name, I used used the default (vBenchmark)
  • Select a resource pool
  • Select a datastore or datastore cluster
  • Select the disk format
  • Select the appropriate (dv)portgroup
  • Fill out the network details
  • Finish

Now after it has been deployed you can power it on. When it is powered on check the summary tab and remember the ip-address (for those using dhcp). You can access the web interface on “http://<ip-address>:8080/”.

Now you will see a config screen. You can simply enter the details of the vCenter Server of the vSphere environment you want to “analyze” and hit “Initiate Query & Proceed to Dashboard”.

Now comes the cool part. vBenchmark will analyze your environment and provide you with a nice clean looking dashboard… but that is not it. You can decide to upload your dataset to VMware and compare it with “peers”. I tried it and noticed their wasn’t enough data for the peer group I selected. So I decided to select “All / All” to make sure I saw something.

I can understand that many of you don’t want to send data to an “unknown” destination. The good thing is though that you can inspect what is being sent. Before you configure the upload just hit “Preview all data to be sent” and you will get a CSV file of the data set. This data is transported over SSL, just in case you were wondering.

I am going to leave this one running for a while and am looking forward to see what the averages are of my peers. I also am wondering what this tool will evolve in to.

One thing that stood out from the “peer results” is the amount of GBs of Storage per VM: 116.40GB. That did surprise me as I would have estimated this to be around 65GB. Anyway, download it and try it out. It is worth it.