What does Automatic activation in Optimize drives do in Windows 11?

Automatic activation in the Optimize Drives service refers to Windows managing disk optimization tasks, such as defragmentation for HDDs and TRIM commands for SSDs, typically on a weekly schedule.

The command netsh int tcp set global autotuninglevel=disabled disables TCP autotuning, which can improve performance in specific scenarios by preventing Windows from dynamically adjusting TCP window sizes during data transfers. This may enhance file copying speeds in some cases, but results can vary depending on system configuration and network conditions.

Disabling TCP auto-tuning can have several negative effects:

1. Reduced Internet Speeds: It limits the TCP receive window to a fixed size (64KB), which can significantly decrease internet speeds, especially on high-bandwidth connections.
2. Increased Latency: Without dynamic adjustment, the system may struggle to optimize data flow, leading to higher latency in network communications
3. Compatibility Issues: While disabling may help with older routers or specific applications, it generally degrades performance in most modern environments where dynamic tuning is beneficial.

Restoring the setting to "normal" is often recommended after testing.