VDI test tools
Login VSI by Login Consultants is the industry-standard tool for testing VDI environments and server-based computing (RDSH environments). It installs a standard collection of desktop application software (such as Microsoft Office and Adobe Acrobat Reader) on each VDI desktop; it then uses launcher systems to connect a specified number of users to available desktops within the environment. Once the user is connected, the workload is started using a login script, which starts the test script once the user environment is configured by the login script. Each launcher system can launch connections to several target machines (for example, VDI desktops).
VDI test methodology
To ensure the optimal combination of end-user experience (EUE) and cost-per-user, performance analysis and characterization (PAAC) testing on Dell VDI solutions is carried out using a carefully designed, holistic methodology that monitors both hardware resource utilization parameters and EUE during load-testing.
For Login VSI, the launchers and Login VSI environment are configured and managed by a centralized management console. Additionally, the following login and boot paradigm is used:
- All users are logged in within a maximum timeframe of one hour. The login rate is determined by the total number of user sessions and the maximum timeframe. For example, with a maximum timeframe of 1 hour (3,600 seconds) and a user session count of 360 sessions, a new user login would be initiated every 10 seconds for the test. The formula for this is Launch Window / Sessions = Overall Logon Rate.
- All desktops are pre-booted in advance of logins commencing.
- The data collection interval for datastores is one minute.
Profiles and workloads
It is important to understand user workloads and profiles when designing a desktop virtualization solution and to understand the density numbers that the solution can support. At Dell Technologies, we use five Login VSI workload/profile levels and three NVIDIA nVector workload/profile levels, each of which is bound by specific metrics and capabilities with two targeted at graphics-intensive use cases. We present more detailed information in relation to these workloads and profiles later in the document, but first it is useful to define the terms “profile” and “workload” as they are used in this document:
- Profile—The configuration of the virtual desktop such as the number of vCPUs and the amount of RAM configured on the desktop that is available to the user.
- Workload—The set of applications that are used by PAAC testing of Dell VDI solutions (for example, Microsoft Office applications, PDF Reader, Internet Explorer, and so on).
Load-testing on each profile is carried out using an appropriate workload that is representative of the relevant use case. The following table shows the load-testing that we used:
Login VSI workload name | Workload description |
Knowledge Worker | Designed for virtual machines with 2 vCPUs. This workload includes the following activities:
|
Resource monitoring
The following sections explain the component monitoring that is used on Dell solutions.
VMware vCenterVMware vCenter is used for VMware vSphere-based solutions to gather key data such as CPU, GPU, memory, disk, and network usage from each of the compute hosts during each test run. This data is exported to .csv files for single hosts and then consolidated to show data from all hosts (when multiple hosts are tested). While the report does not include specific performance metrics for the Management host servers, these servers are monitored during testing to ensure that they are performing at an expected performance level with no bottlenecks.
Resource utilizationThe purpose of this test was to determine the user density at a reasonable system load. Testing to system failure was out of scope. To achieve a reasonable system load, target thresholds for system resources were set as shown in the following table. These thresholds reflect a system that is well utilized, but not near failure.
Parameter | Pass/fail threshold |
Average CPU usage | 85% |
Average CPU core utilization | 85% |
Average CPU readiness | 10% |
Average memory utilization (active) | 85% |
Consumed memory | <100% |
Memory ballooning | 0 |
Memory swapping | 0 |
Network throughput | 85% |
Cluster storage latency | 20 milliseconds (ms) |
Disk latency | 20 ms |
Spare capacity | 15% |
Test configuration details
The following tables list the hardware and software components of the infrastructure that was used for the PAAC test. All host machines were updated with the latest operating system and security updates.
The following table shows the hardware components:
Hardware type | Component |
Compute host hardware | 16 x PowerEdge R750 Servers
|
Management host hardware | R730 |
Storage | Dell PowerStore 9200 T
|
Network | S5248-ON Switch |
The following table shows the software components:
Software type | Program/version |
Display protocol | BLAST Extreme H.264 + Switch Codec |
Broker | VMware Horizon 8.4 |
Hypervisor | vSphere ESXi 7.0.3 |
SQL | Microsoft SQL Server 2019 |
Desktop operating system | Microsoft Windows 10 Enterprise 64-bit (version 21H2) |
Office software | Microsoft Office 365 / 2019 |
Management operating system | Microsoft Windows Server 2019 |
Login VSI version | 4.1.40.1 |
Antivirus software | Windows Defender |
The following table summarizes the standard PAAC VM configurations for Login VSI currently used for the various profiles/workloads tested:
Workload | VM profiles | ||||
vCPUs | RAM | RAM reserved | Desktop video resolution | Operating system | |
Knowledge Worker | 2 | 4 GB | 2 GB | 1920 x 1080 | Windows 10 Enterprise 64-bit |