A feature designed to make Windows updates faster is now being blamed for slowing down PCs by consuming excessive system memory. Users and tech observers have identified a potential memory leak within Windows 11's Delivery Optimization service, raising concerns about its impact on system performance and resource management.
Affected Windows Service: Delivery Optimization (DoSvc) Core Issue: Suspected memory leak, causing RAM usage to increase over time without release. User-Reported Impact: Up to 20GB of RAM consumption in extreme cases. Default Status: Enabled and set to start automatically on most Windows 11 PCs. Primary Function: Peer-to-peer (P2P) system for sharing Windows Update and Microsoft Store app files to speed up downloads.
A Well-Intentioned Feature Turns Problematic
Delivery Optimization is a peer-to-peer (P2P) content delivery system built into Windows 10 and 11. Its primary function is to speed up the download of Windows updates and Microsoft Store applications by sharing parts of already-downloaded files with other PCs on a local network or over the internet. This approach is intended to reduce bandwidth consumption for users and lessen the load on Microsoft's own servers, creating a more efficient update ecosystem. However, this efficiency seems to come at a hidden cost for some users, transforming a helpful tool into a resource drain.
The Evidence of a Memory Leak
The issue came to light through user reports and investigation. A Reddit user named Niff_Naff provided a detailed analysis, tracking the process ID of the Delivery Optimization service (DoSvc) and graphing its memory usage over time. The results were concerning: the service's memory consumption showed a clear and steady increase, not releasing memory back to the system. This pattern is a classic indicator of a software memory leak, where a program fails to free up memory it no longer needs. Some users reported extreme cases, with the service allegedly consuming up to 20GB of RAM, effectively crippling their system's performance. The problem is compounded by the service's default "automatic" startup setting, meaning it runs in the background on most Windows 11 PCs without user intervention.
A Second Suspect Emerges
The Delivery Optimization issue is not the only recent resource management problem flagged by the Windows community. Following a recent system update for Windows 11 versions 24H2 and 25H2 (specifically KB5072033), Microsoft changed the startup type of the AppX Deployment Service (Appxsvc) from "manual" to "automatic." This service, responsible for deploying and managing app packages from the Microsoft Store, has also been known to cause high CPU, memory, and disk usage. The combination of these two services operating automatically has left some users feeling their systems are under constant siege from Microsoft's own background processes.
Related Service Issue: AppX Deployment Service (Appxsvc) Change Noted: Startup type changed from "Manual" to "Automatic" with update KB5072033 (for Win11 24H2/25H2). Known Impact: Can cause high CPU, memory, and disk usage. Function: Manages deployment and operations of AppX packages (Microsoft Store apps).
How to Regain Control of Your System Resources
Fortunately, users are not powerless against these "memory刺客" or memory assassins. The Delivery Optimization feature can be safely disabled, though with one notable trade-off: download speeds for Windows updates and Store apps will revert to standard rates, as they will no longer utilize the P2P network. To turn it off, users need to navigate to Settings > Windows Update > Advanced Options > Delivery Optimization. Here, they can toggle off the switch for "Allow downloads from other devices." For a more moderate approach, users can limit the sharing to "PCs on my local network" only, which may reduce the service's external activity and associated resource use.
Steps to Disable Delivery Optimization:
- Open Settings (Windows Key + I).
- Go to Windows Update.
- Click Advanced options.
- Select Delivery Optimization.
- Toggle off "Allow downloads from other devices". Alternative: Set downloads to come from "PCs on my local network" only.
The Broader Context for Microsoft
This incident occurs during a transitional period for Microsoft's operating system. The company ended support for the widely used Windows 10 in late 2025 and has since focused on its successor. The recent Windows 11 25H2 update was noted for its minimal changes, making performance and stability issues like this memory leak particularly noticeable and frustrating for users. For a company that has long championed the efficiency of its software ecosystem, recurring background service problems that degrade the user experience are a significant reputational concern. The tech community now awaits an official response or patch from Microsoft to address the underlying code issue in the Delivery Optimization service, rather than relying on users to manually work around it.