A closer look at the WVD IOPS values
Posted February 2021 10 minute read
Do you get what you paid for?, Microsoft advertises certain IO speeds regarding their storage tiers for Windows Virtual Desktops, or WVD in short.
How do these figures hold up to measured values? We used the VDI Drones benchmarking tool to give an answer to that question.
We are aware that the results are a sample taken on a certain time, and we, by no means, claim that this is the ultimate truth. These figures are an indication and are subject to interpretation.
We used the following WVD type with all three tests;
Disk Tier | SSD Premium (P10) | SSD Standard (E10) | HDD Standard (S10) |
Provisioned IOPS | 500 IOPS | 500 IOPS | 500 IOPS |
Provisioned throughput | 100 MBps | 60 MBps | 60 MBps |
Max Burst-IOPS | 3500 IOPS | – | – |
Max Burst throughput | 170 MBps | – | – |
Disk type | SSD Premium | SSD Standard | HDD Standard |
I/O Score | 798.7 | 656.9 | 679.6 |
4k Write | 1783 IOPS | 683 IOPS | 601 IOPS |
4k Read | 3016 IOPS | 2903 IOPS | 3278 IOPS |
4k-64 Write | 43.1 MB/s | 38.5 MB/s | 43.4 MB/s |
4k-64 Read | 250 MB/s | 249 MB/s | 265 MB/s |
Sequential Write | 77.8 MB/s | 82.1 MB/s | 86 MB/s |
Sequential Read | 774 MB/s | 773 MB/s | 777 MB/s |
Write Access | 1431 IOPS | 861 IOPS | 908 IOPS |
Read Access | 33201 IOPS | 33146 IOPS | 33142 IOPS |
What is the difference between different virtual machines in Azure? We took a small sample of the most common used virtual machines to demonstrate the difference between them using the VDI Drones benchmark tool.
The D-series Azure Virtual Machines offer a combination of vCPUs, memory, and temporary storage able to meet the requirements associated with most production workloads. We took these machines as test compartments because of frequent use and easy scale ability. In these tables you can see the difference in capacity between the virtual machines. This demonstrates the usefulness of the tool, testing before bigger scale implementations and finding the right fit for your environment.
DS1_v2 – 1 vcpu 3.5 Gib memory | DS2_v2 – 2 vcpu 7 Gib memory | DS3_v2 – 4 vcpu 14 Gib memory | |
CPU Score | 709 | 1026.5 | 1760.4 |
ALU Stress – single core | 435 MIPS | 444 MIPS | 547 MIPS |
ALU Stress – Multicore | 429 MIPS | 902 MIPS | 2332 MIPS |
FPU Stress – Single Core | 442 MIPS | 451 MIPS | 547 MIPS |
FPU Stress – MultiCore | 435 MIPS | 899 MIPS | 2396 MIPS |
Encryption – single core | 53.5 Mib/s | 60.6 Mib/s | 72.9 Mib/s |
Encryption – Multicore | 47.7 Mib/s | 111 Mib/s | 277 Mib/s |
Compress – single core | 10597 KiB/s | 11538 KiB/s | 13561 KiB/s |
Compress – Multicore | 10721 KiB/s | 22228 KiB/s | 58765 KiB/s |
Cache – L1 | 1.72 ns | 1.66 ns | 1.24 ns |
DS1_v2 – 1 vcpu 3.5 Gib memory | DS2_v2 – 2 vcpu 7 Gib memory | DS3_v2 – 4 vcpu 14 Gib memory | |
Memory Score | 1086.5 | 1634.6 | 1808.8 |
Memory copy | 920 MB/s | 1645 MB/s | 1862 MB/s |
Memory latency | 78 ns | 61.6 ns | 56.9 ns |
DS1_v2 – 1 vcpu 3.5 Gib memory | DS2_v2 – 2 vcpu 7 Gib memory | DS3_v2 – 4 vcpu 14 Gib memory | |
I/O Score | 498.8 | 795 | 1624.8 |
4k Write | 465 IOPS | 992 IOPS | 3989 IOPS |
4k Read | 3741 IOPS | 4110 IOPS | 12940 IOPS |
4k-64 Write | 64.6 MB/s | 69.2 MB/s | 86.4 MB/s |
4k-64 Read | 304 MB/s | 486 MB/s | 669 MB/s |
Sequential Write | 33.6 MB/s | 53.4 MB/s | 109 MB/s |
Sequential Read | 220 MB/s | 509 MB/s | 994 MB/s |
Write Access | 458 IOPS | 963 IOPS | 1907 IOPS |
Read Access | 33011 IOPS | 44424 IOPS | 78821 IOPS |
The measured values are pretty much equal or better than advertised. Although the advertised values are not specific in terms of write/read.
An other thing to take away from this test, the processor configuration has a big impact on the IO performance. It be no surprise that you should equip IO heavy loads on WVD machines with at least 4 vCPU’s.
One remarkable thing is ofcourse the HDD standard outperforming the standard SSD. We need to get in contact with Microsoft on that. We all suspect that they are not actual harddisk provisioned, but are indeed also SSD’s. Since almost no-one will select a HDD when provisioning new Windows Virtual Desktops, this could explain better performance measured, but this remains unclear.
Want to have a go yourself?, start measuring your virtual desktop with our free benchmark software.