Announcing Native NVMe in Windows Server 2025: Ushering in a New Era of Storage Performance
We’re thrilled to announce the arrival of Native NVMe support in Windows Server 2025—a leap forward in storage innovation that will redefine what’s possible for your most demanding workloads. Modern NVMe (Non-Volatile Memory Express) SSDs now operate more efficiently with Windows Server. This improvement comes from a redesigned Windows storage stack that no longer treats all storage devices as SCSI (Small Computer System Interface) devices—a method traditionally used for older, slower drives. By eliminating the need to convert NVMe commands into SCSI commands, Windows Server reduces processing overhead and latency. Additionally, the whole I/O processing workflow is redesigned for extreme performance. This release is the result of close collaboration between our engineering teams and hardware partners, and it serves as a cornerstone in modernizing our storage stack. Native NVMe is now generally available (GA) with an opt-in model (disabled by default as of October’s latest cumulative update for WS2025). Switch onto Native NVMe as soon as possible or you are leaving performance gains on the table! Stay tuned for more updates from our team as we transition to a dramatically faster, more efficient storage future. Why Native NVMe and why now? Modern NVMe devices—like PCIe Gen5 enterprise SSDs capable of 3.3 million IOPS, or HBAs delivering over 10 million IOPS on a single disk—are pushing the boundaries of what storage can do. SCSI-based I/O processing can’t keep up because it uses a single-queue model, originally designed for rotational disks, where protocols like SATA support just one queue with up to 32 commands. In contrast, NVMe was designed from the ground up for flash storage and supports up to 64,000 queues, with each queue capable of handling up to 64,000 commands simultaneously. With Native NVMe in Windows Server 2025, the storage stack is purpose-built for modern hardware—eliminating translation layers and legacy constraints. Here’s what that means for you: Massive IOPS Gains: Direct, multi-queue access to NVMe devices means you can finally reach the true limits of your hardware. Lower Latency: Traditional SCSI-based stacks rely on shared locks and synchronization mechanisms in the kernel I/O path to manage resources. Native NVMe enables streamlined, lock-free I/O paths that slash round-trip times for every operation. CPU Efficiency: A leaner, optimized stack frees up compute for your workloads instead of storage overhead. Future-Ready Features: Native support for advanced NVMe capabilities like multi-queue and direct submission ensures you’re ready for next-gen storage innovation. Performance Data Using DiskSpd.exe, basic performance testing shows that with Native NVMe enabled, WS2025 systems can deliver up to ~80% more IOPS and a ~45% savings in CPU cycles per I/O on 4K random read workloads on NTFS volumes when compared to WS2022. This test ran on a host with Intel Dual Socket CPU (208 logical processors, 128GB RAM) and a Solidigm SB5PH27X038T 3.5TB NVMe device. The test can be recreated by running "diskspd.exe -b4k -r -Su -t8 -L -o32 -W10 -d30 testfile1.dat > output.dat" and modifying the parameters as desired. Results may vary. Top Use Cases: Where You’ll See the Difference Try Native NVMe on servers running your enterprise applications. These gains are not just for synthetic benchmarks—they translate directly to faster database transactions, quicker VM operations, and more responsive file and analytics workloads. SQL Server and OLTP: Shorter transaction times, higher IOPS, and lower tail latency under mixed read/write workloads. Hyper‑V and virtualization: Faster VM boot, checkpoint operations, and live migration with reduced storage contention. High‑performance file servers: Faster large‑file reads/writes and quicker metadata operations (copy, backup, restore). AI/ML and analytics: Low‑latency access to large datasets and faster ETL, shuffle, and cache/scratch I/O. How to Get Started Check your hardware: Ensure you have NVMe-capable devices that are currently using the Windows NVMe driver (StorNVMe.sys). Note that some NVMe device vendors provide their own drivers, so unless using the in-box Windows NVMe driver, you will not notice any differences. Enable Native NVMe: After applying the 2510-B Latest Cumulative Update (or most recent), add the registry key with the following PowerShell command: reg add HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Policies\Microsoft\FeatureManagement\Overrides /v 1176759950 /t REG_DWORD /d 1 /f Alternatively, use this Group Policy MSI to add the policy that controls the feature then run the local Group Policy Editor to enable the policy (found under Local Computer Policy > Computer Configuration > Administrative Templates > KB5066835 251014_21251 Feature Preview > Windows 11, version 24H2, 25H2). Once Native NVMe is enabled, open Device Manager and ensure that all attached NVMe devices are displayed under the “Storage disks” section. Monitor and Validate: Use Performance Monitor and Windows Admin Center to see the gains for yourself. Or try DiskSpd.exe yourself to measure microbenchmarks in your own environment! A quick way to measure IOPS in Performance Monitor is to set up a histogram chart and add a counter for Physical Disk>Disk Transfers/sec (where the selected instance is a drive that corresponds to one of your attached NVMe devices) then run a synthetic workload with DiskSpd. Compare the numbers before and after enabling Native NVMe to see the realized difference in your real environment! Join the Storage Revolution This is more than just a feature—it’s a new foundation for Windows Server storage, built for the future. We can’t wait for you to experience the difference. Share your feedback, ask questions, and join the conversation. Let’s build the future of high-performance Windows Server storage together. Send us your feedback or questions at nativenvme@microsoft.com! — Yash Shekar (and the Windows Server team)
Unable to Build Switchless Storage using Network ATC
3-Node HV/S2D Cluster using Switchless Storage and Network ATC getting Network HUD Error I have a Dell 3-node server cluster being used to host Hyper-V with S2D. Each node is identical and certified to pass S2D requirements. The networking consists of 2 onboard 1 Gbps and 2 quad-port PCI(e) NICs at 10/25 Gbps. The 2 onboard ports are being used for the management intent, 2 ports from each of those NICs are being connected to 2 top-of-rack switches for the compute intent at a total of 12 10 Gbps connections, and the other 2 ports from each of those NICs are being connected directly to the other nodes in a dual mesh method for the storage intent at a total of 6 25 Gbps connections. Very similar to the Microsoft diagram for a three-node storage switchless, dual TOR, dual link deployment network reference pattern for Azure Local, but I am using Windows Server 2025 Datacenter, not Azure Local. The problem I am encountering is when I attempt to create the switchless storage intent, I get an error (shown below) that reads "Failed to fetch physical NIC mapping from the Network HUD service. Please diagnose..." If I leave off the switchless option, it builds without issue. The error only occurs when I attempt to use the switchless option. I tried without configuring the NIC IP addresses first, as well as trying configuring the NIC IP addresses beforehand. I tried without having a cluster built first, as well as building a failover cluster without storage before running the network intent command. The error I posted below shows my last attempt after having the NICs configured with IP addresses and having a failover cluster established before running the command. The error has remained the same throughout the process. Has anyone else run into an issue like this with switchless storage? It seems like everything that I am trying to do is within scope and should be a supported solution. My fallback plan is to use my existing switches, but that drops my connection speeds down from 25 Gbps to 10 Gbps due to hardware limitations.
HLK test failing for a KMDF driver with error “A lower driver failed IRP_MN_QUERY_STOP_DEVICE”
Subject: HLK DF‑PNP Rebalance Fail Restart Device: E: target widens to all volumes; QueryStop fails even without my driver installed. Hi all, I’m trying to pass all HLK tests for my driver. Driver: KMDF PnP volume upper‑filter (attached via UpperFilters to the Volume/Disk class) OS: Windows Server 2016 Datacenter, build 14393 HLK: 10.1.14393.8069 Test: DF - PNP Rebalance Fail Restart Device (Reliability) Target volume: E: (NTFS) Storage: PERC H330 Mini (DELL) (HBA) Observed behavior The DQ initially targets E:, but the test later widens to all STORAGE\Volume devnodes: WDTF_TARGETS : INFO : - Query("IsDevice AND (DriverBinaryNames!='i8042prt.sys') AND (Class!=hdc) AND (Class!=scsiadapter) AND (DsmDevice!=TRUE) AND (IsDevice AND (DriverBinaryNames!='i8042prt.sys') AND (Class!=hdc) AND (Class!=scsiadapter) AND (DsmDevice!=TRUE) AND (DeviceID='STORAGE\VOLUME{01FEB6F1-3717-11F1-9707-806E6F6E6963}#0000000001000000'))") WDTF_TARGETS : INFO : Target: Volume (E:) STORAGE\VOLUME{01FEB6.. WDTF_SUPPORT : INFO : - ClearSetupAPILogs() WDTF_TARGETS : INFO : - Query("IsDevice AND (SemiUniqueTargetHardwareIdentifier='STORAGE\Volume')") WDTF_TARGETS : INFO : Target: Volume STORAGE\VOLUME{01FEB6.. WDTF_TARGETS : INFO : Target: Volume STORAGE\VOLUME{01FEB6.. WDTF_TARGETS : INFO : Target: Volume (C:) STORAGE\VOLUME{01FEB6.. WDTF_TARGETS : INFO : Target: Volume (E:) STORAGE\VOLUME{01FEB6.. Failures report A lower driver failed IRP_MN_QUERY_STOP_DEVICE and PNP.RestartDevice() Win32=1 - Incorrect function. For each of the 4 target volumes, it shows this error, DTF_PNP : INFO : - EDTTryStopDeviceFailRestart() WDTF_PNP : INFO : Target: Volume (C:) STORAGE\VOLUME{01FEB6EF-3717-11F1-9707-806E6F6E6963}#000000001F500000 WDTF_PNP : INFO : Result: A lower driver failed IRP_MN_QUERY_STOP_DEVICE. Rebalance tests cannot proceed... WDTF_PNP : INFO : - EDTTryStopDeviceFailRestart() WDTF_PNP : INFO : Target: Volume (E:) STORAGE\VOLUME{01FEB6F1-3717-11F1-9707-806E6F6E6963}#0000000001000000 WDTF_PNP : INFO : Result: A lower driver failed IRP_MN_QUERY_STOP_DEVICE. Rebalance tests cannot proceed... WDTF_PNP : ERROR : PNP.RestartDevice() Win32=1 - Incorrect function. WDTF_PNP : ERROR : PNP.RestartDevice() Win32=1 - Incorrect function. Q1. I have tried multiple variations of the DQ query, and each successfully targets the E volume only. Why does this test later widen to all volumes even when DQ targets only E:? How can I force it to stay on E: ? Q2. I also ran this on a physical server client and a VM client, but faced the same issue both times. I understand the system/boot volume may veto QueryStop, but why does each volume report ‘a lower driver failed IRP_MN_QUERY_STOP_DEVICE’ in this test? Q3. I uninstalled my driver completely and still see the same failures when the test is running with only inbox drivers (e.g., msdmfilt.sys, volsnap.sys, volume.sys) listed by Driver Verifier for target E in the logs. That makes me suspect setup/config rather than my driver. Why would only these drivers fail the test as well, what am I missing here? WDTF_DRIVER_VERIFIER : INFO : - EnableOnAllDriversOfDevices() WDTF_DRIVER_VERIFIER : INFO : Target: Volume (E:) STORAGE\VOLUME{01FEB6F1-3717-11F1-9707-806E6F6E6963}#0000000001000000 WDTF_DRIVER_VERIFIER : INFO : Driver: msdmfilt.sys WDTF_DRIVER_VERIFIER : INFO : Driver: volsnap.sys WDTF_DRIVER_VERIFIER : INFO : Driver: volume.sys Thanks for any guidance!
