If your Mac has been left running for an extended period and starts to feel unusually slow, there may be a technical reason behind it. Researchers have identified a macOS issue that appears after roughly 49 days of continuous uptime, affecting how the system handles network activity.

The problem is linked to how macOS tracks time for managing connections. Once a specific limit is reached, the system struggles to properly close completed network sessions. These inactive connections begin to accumulate, eventually using up all available connection slots.

When that happens, new internet connections fail to open. Websites stop loading and apps relying on the internet may stop responding, even though some existing connections continue to work. This can make the issue difficult to identify at first.

As the number of unused connections grows, the processor also works harder to manage them, which contributes to the slowdown users notice.

For now, the most practical solution is to restart the device before reaching this uptime limit. A reboot clears the connection count and restores normal performance, making periodic restarts a simple way to avoid the issue.