Table of Contents
Windows Server remains the backbone of many EUC environments, whether it is hosting session-based workloads, published applications, or the supporting infrastructure around a virtual desktop deployment. With Windows Server 2025 now generally available, and Windows Server 2019 approaching the end of its extended support window in January 2029, many organizations are planning their migration path. For the EUC community, the recurring question with every new Server release is the same one asked of every new client OS: what does the newer version cost in terms of resource consumption?
This GO-EUC research compares Windows Server 2019, 2022, and 2025 side by side under an identical single-user knowledge worker workload, to isolate how the resource footprint of the operating system itself has evolved across the three releases.
Three releases, three generations of Windows
Although all three operating systems carry the Windows Server name, they are built on very different foundations. Windows Server 2019 is based on the Windows 10 1809 codebase, Windows Server 2022 on the Windows 10 21H2-era codebase, and Windows Server 2025 on the Windows 11 24H2 codebase. Each generational jump brings not only new features, such as hotpatching, SMB over QUIC, and improved storage performance in Server 2025, but also the accumulated services, security capabilities, and background activity of a newer Windows core.
The results in this research reflect the following fully updated builds at the time of testing:
- Windows Server 2019 - Version 1809 (OS Build 17763.9020)
- Windows Server 2022 - Version 21H2 (OS Build 20348.5386)
- Windows Server 2025 - Version 24H2 (OS Build 26100.32995)
Setup and scenarios
To test the hypothesis, Login Enterprise is used to generate a consistent user load, running the standard Knowledge Worker 2022 workload. This workload simulates a typical office user working with applications such as Microsoft Office and the Microsoft Edge browser, which is also used for viewing PDF documents, making it representative of the average knowledge worker profile.
The following three scenarios are part of this research:
- Windows Server 2019
- Windows Server 2022
- Windows Server 2025
Each scenario runs as a single virtual machine on Nutanix Community Edition (CE), which uses the KVM-based AHV hypervisor. The host is equipped with two AMD EPYC 7551 32-core processors, 512 GB of memory, and all-NVMe storage. Each virtual machine is configured with 8 vCPUs, 32 GB of memory, and a 64 GB disk. A single user connects to each virtual machine over RDP and runs the workload for the full test duration.
It is important to note that this research does not measure single-server scalability (SSI) or host scalability. With only one user session on one virtual machine per test, there is no resource contention from neighboring machines or sessions, and no conclusions can be drawn about how many users a session host can support on any of these versions. The goal of this comparison is to isolate the resource footprint of the operating system itself; translating these results into user density figures would require a dedicated multi-session or multi-VM scalability test, which is a good candidate for follow-up research.
To ensure consistent and reliable results, Microsoft Defender is completely disabled so it does not influence the benchmark results. Please note that this is not considered a best practice in a production environment, but it is a common approach in benchmarking scenarios where the goal is to isolate and measure the impact of a specific component or configuration change. Beyond that, no additional services or roles are installed, and a power plan is applied to keep each virtual machine always on and running during the test runs.
Apart from the Windows Server version, all hardware, software, benchmark settings, and virtual machine configurations remain identical throughout the research.
During each benchmark run, telemetry is collected from the virtual machine, including CPU utilization, memory usage, disk reads and writes per second, and disk queue length.
Hypothesis and results
Given that each release is built on a progressively newer Windows codebase, a gradual increase in resource consumption is the reasonable expectation: each generation ships with more services, more security features enabled by default, and a heavier desktop experience. The most interesting question is not whether Server 2025 consumes more than Server 2019, but by how much, and whether the step from 2022 to 2025, the migration most organizations currently face, is larger than the step from 2019 to 2022.
Let’s start with the CPU utilization from the virtual machine perspective.
The first observation is that the overall CPU utilization is very low across the board, which is expected with a single user on an 8 vCPU virtual machine. The pattern, however, is consistent with the hypothesis: Server 2019 averages 1.32%, Server 2022 averages 1.51%, and Server 2025 averages 2.08%. In relative terms, Server 2025 consumes roughly 58% more CPU than Server 2019 and 38% more than Server 2022 to run the exact same workload. The peak utilization tells a similar story, climbing from 7.8% on Server 2019 to 9.6% on Server 2022 and 16.6% on Server 2025, more than double the Server 2019 peak. At these absolute levels a single user will not notice the difference, but in a multi-session RDSH scenario, where dozens of users share the same host, a per-session CPU increase of this magnitude would compound and directly affect user density.
The memory footprint shows the clearest generational growth.
The average memory usage increases from 8.4% on Server 2019 to 10.6% on Server 2022 and 14.6% on Server 2025. To put this into perspective on a 32 GB virtual machine: Server 2019 uses approximately 2.7 GB, Server 2022 approximately 3.4 GB, and Server 2025 approximately 4.7 GB. That means the operating system alone claims roughly 2 GB more memory on Server 2025 than on Server 2019, and about 1.3 GB more than on Server 2022, before any additional users or applications are added. For session host sizing, this is arguably the most important number in this research: the baseline OS overhead directly reduces the memory available for user sessions.
The next charts zoom in on the storage perspective.
Disk reads are effectively identical across the three versions, averaging between 41 and 46 reads per second. This is expected, as read activity is primarily driven by the workload itself, which is the same in all three scenarios. Disk writes show a more noticeable difference: Server 2019 averages 82 writes per second, while Server 2022 and Server 2025 average 109 and 115 respectively, an increase of roughly a third over Server 2019. This aligns with the general trend of newer Windows versions generating more logging, telemetry, and background maintenance activity. On the all-NVMe storage used in this research the additional writes are absorbed without any measurable effect, but on shared or write-sensitive storage platforms it is a difference worth being aware of when consolidating many virtual machines.
The current disk queue length confirms that the storage subsystem is never under pressure during the tests. The averages are near zero for all three versions, and although Server 2025 records a briefly higher peak of 8.2, this is a momentary spike rather than sustained queuing, and there is no meaningful difference between the three releases from a storage latency perspective.
Conclusion
This comparison confirms the expected generational trend: each newer Windows Server release carries a heavier resource footprint than its predecessor when running an identical single-user knowledge worker workload. Windows Server 2025 consumes roughly 58% more CPU on average than Server 2019 and approximately 2 GB more memory as a baseline, with Server 2022 sitting between the two on both metrics. Disk reads remain workload-driven and identical across versions, while disk writes increase by roughly a third from Server 2019 to the two newer releases, without ever putting the storage subsystem under pressure.
For EUC architects and administrators planning a migration, the practical takeaway is in the sizing. In absolute terms, the differences measured here are small for a single user, and none of them will be perceptible in day-to-day use. But session hosts are shared machines, and baseline OS overhead is paid once per virtual machine while per-session overhead is paid for every user. The roughly 1.3 GB higher memory baseline of Server 2025 compared to Server 2022, and the measurably higher CPU activity, suggest that a like-for-like replacement of session hosts may support fewer users per host, or require slightly larger virtual machines to maintain the same density.
As this research measures a single user on a single virtual machine in isolation, that density impact remains to be proven. A dedicated multi-session scalability test comparing Server 2022 and Server 2025 as RDSH workloads would be the logical follow-up, and given that Server 2019 leaves extended support in January 2029, it is a question many organizations will need answered sooner rather than later.
Question to our readers: Are you planning to move your session hosts directly from Windows Server 2019 to Server 2025, or are you taking the intermediate step via Server 2022? And does OS resource overhead factor into that decision, or is it driven purely by support lifecycles?
Photo by Scott Rodgerson on Unsplash
