juicedata/juicefs · error

mount point mismatch: %s %s

Error message

mount point mismatch: 
%s
%s

What it means

Returned by checkPort when the pprof cmdline of the process on the discovered port does not contain the expected mount point argument. The debug tool connected to a pprof service, but it belongs to a different JuiceFS mount, so collecting diagnostics for the requested mount would be wrong.

Source

Thrown at cmd/debug.go:266

}

// check pprof service status
func checkPort(port int, amp string) error {
	url := fmt.Sprintf("http://localhost:%d/debug/pprof/cmdline?debug=1", port)
	resp, err := getRequest(url, 3*time.Second)
	if err != nil {
		return fmt.Errorf("error checking pprof alive: %v", err)
	}
	resp = bytes.ReplaceAll(resp, []byte{0}, []byte{' '})
	fields := strings.Fields(string(resp))
	flag := false
	for _, field := range fields {
		if amp == field {
			flag = true
		}
	}
	if !flag {
		return fmt.Errorf("mount point mismatch: \n%s\n%s", resp, amp)
	}
	return nil
}

type metricItem struct {
	name, url string
}

func reqAndSaveMetric(name string, metric metricItem, outDir string, timeout time.Duration) error {
	resp, err := getRequest(metric.url, timeout)
	if err != nil {
		return fmt.Errorf("error getting metric: %v", err)
	}
	retPath := filepath.Join(outDir, fmt.Sprintf("juicefs.%s", metric.name))
	retFile, err := os.Create(retPath)
	if err != nil {
		logger.Fatalf("error creating metric file %s: %v", retPath, err)
	}

View on GitHub (pinned to c9a67b23e8)

Solutions

1. Verify the pid/mount-point pair passed to `juicefs debug` corresponds to the right process

When it happens

Trigger: Thrown at cmd/debug.go:266 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of juicedata/juicefs@c9a67b23e8 (2026-09-06). Data as JSON: /api/errors/9780bda4ed35de8c. Report an issue: GitHub.