Jetson core check fails to execute tegrastats in Agent 7.78.0

[junyu-junyu]

Summary

The NVIDIA Jetson core check fails in Datadog Agent 7.78.0 when running tegrastats.

The check builds a shell command string like:

(/usr/bin/tegrastats --interval 500) & pid=$!; (sleep 1 && kill -9 $pid)

but in Agent 7.78.0 it is passed directly to exec.CommandContext(ctx, cmdStr), so Go tries to execute the entire shell expression as a binary path.

This causes errors such as:

fork/exec (/usr/bin/tegrastats --interval 500) & pid=$!; (sleep 1 && kill -9 $pid): no such file or directory

When use_sudo: true, it also fails because sudo receives the shell expression as a command without sh -c:

tegrastats did not produce any output: exit status 1. Stderr: usage: sudo ...

Affected version

• Datadog Agent: 7.78.0
• Platform: NVIDIA Jetson / Ubuntu 18.04 / aarch64
• Integration: jetson

Configuration

instances:
  -
    tegrastats_path: /usr/bin/tegrastats
    use_sudo: false

With use_sudo: true, the error changes to the sudo usage output, but the root cause appears to be the same missing shell invocation.

Observed behavior

Running:

/opt/datadog-agent/bin/agent/agent check jetson

returns:

Error: fork/exec (/usr/bin/tegrastats --interval 500) & pid=$!; (sleep 1 && kill -9 $pid): no such file or directory

The service logs show repeated failures:

check:jetson | Error running check: tegrastats did not produce any output

Expected behavior

The Jetson check should execute tegrastats, collect one sample, parse it, and submit nvidia.jetson.* metrics.

Source code difference

In Agent 7.76.3, the check used sh -c:

if c.useSudo {
    cmd = exec.Command("sudo", "-n", "sh", "-c", cmdStr)
} else {
    cmd = exec.Command("sh", "-c", cmdStr)
}

Reference:

https://github.com/DataDog/datadog-agent/blob/7.76.3/pkg/collector/corechecks/nvidia/jetson/jetson.go#L124-L135

In Agent 7.78.0, this changed to:

if c.useSudo {
    cmd = exec.CommandContext(ctx, "sudo", "-n", cmdStr)
} else {
    cmd = exec.CommandContext(ctx, cmdStr)
}

Reference:

https://github.com/DataDog/datadog-agent/blob/7.78.0/pkg/collector/corechecks/nvidia/jetson/jetson.go#L146-L162

Because cmdStr contains shell syntax such as parentheses, &, $!, ;, and &&, it must be executed via sh -c.

Suggested fix

Use exec.CommandContext while preserving sh -c, for example:

if c.useSudo {
    cmd = exec.CommandContext(ctx, "sudo", "-n", "sh", "-c", cmdStr)
} else {
    cmd = exec.CommandContext(ctx, "sh", "-c", cmdStr)
}

Alternatively, avoid shell syntax entirely by starting tegrastats directly with args and handling timeout/process termination in Go.

Workaround

A local symlink/wrapper workaround can make the invalid executable path resolve, but this is not ideal and should not be required.

[Enzu83]

Hello, thanks for your contribution!

We are aware of this bug, it will be fixed in the upcoming 7.79.0 release. I'll keep you updated.