What is symptomsd on a Mac?
symptomsd watches network health and keeps per app network usage. It ran as _networkd at 0.4% to 0.6% CPU and 5 to 9 MB on our Mac. What it does and when it spikes.
What is symptomsd?
symptomsd watches the network for problems, such as a stalled connection, a dead Wi-Fi network or DNS failures, so macOS can switch networks or report the issue. It also keeps the per app network usage figures. It lives at /usr/libexec/symptomsd and runs as _networkd.
| Reading on our Mac | Value |
|---|---|
| CPU | 0.4% to 0.6% |
| Memory | 5 to 9 MB |
| Running for | since start up, 30 hours |
Why is symptomsd using CPU?
- Many network connections opening and closing, which it watches.
- Network changes: switching Wi-Fi networks, a VPN connecting, waking from sleep.
- A flaky network that keeps failing and recovering.
A small steady load is normal. Higher load that follows you from network to network points to an app making connections in a loop; see which app is using the internet.
See it live
Free Mac's System tab ranks every process by processor use and energy impact, once a second, and marks the ones macOS will not let you quit as protected. See also mDNSResponder.
Related: thermalmonitord and secd.
Common questions
What is symptomsd on a Mac?
A macOS process that watches network health and keeps per app network usage.
Why is symptomsd using CPU?
Network changes or many connections. A small steady load is normal.
Is symptomsd safe?
Yes. It is part of macOS, at /usr/libexec/symptomsd.