Add support for ctrl+c

This commit is contained in:
Sebastiaan de Schaetzen 2025-03-14 14:17:38 +01:00
parent 11b62aa1f0
commit 8d36e1e245

234
main.go
View File

@ -1,14 +1,17 @@
package main
import (
"context"
"encoding/json"
"fmt"
"log"
"net/http"
"os"
"os/exec"
"os/signal"
"strings"
"sync"
"syscall"
"time"
"github.com/NVIDIA/go-nvml/pkg/nvml"
@ -29,13 +32,14 @@ const (
)
type ResourceUsage struct {
timestamp time.Time
cpuUsage float64
gpuUsage float64
diskIO uint64
networkIO uint64
sshConnections int
activeUsers int
Timestamp time.Time `json:"timestamp"`
CpuUsage float64 `json:"cpu_usage"`
GpuUsage float64 `json:"gpu_usage"`
GpuAvailable bool `json:"gpu_available"`
DiskIO uint64 `json:"disk_io"`
NetworkIO uint64 `json:"network_io"`
SshConnections int `json:"ssh_connections"`
ActiveUsers int `json:"active_users"`
}
type SystemStatus struct {
@ -46,6 +50,7 @@ type SystemStatus struct {
var (
currentStatus SystemStatus
statusMutex sync.RWMutex
nvmlAvailable bool
)
func main() {
@ -58,11 +63,22 @@ func main() {
ret := nvml.Init()
if ret != nvml.SUCCESS {
log.Printf("Warning: Could not initialize NVML: %v", ret)
nvmlAvailable = false
} else {
nvmlAvailable = true
defer nvml.Shutdown()
}
defer nvml.Shutdown()
// Start HTTP server
go startHTTPServer()
// Create a context that we'll use to shut down the application
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
// Set up signal handling
sigChan := make(chan os.Signal, 1)
signal.Notify(sigChan, syscall.SIGINT, syscall.SIGTERM)
// Start HTTP server with context
srv := startHTTPServer(ctx)
usageHistory := make([]ResourceUsage, 0)
ticker := time.NewTicker(checkInterval)
@ -70,49 +86,85 @@ func main() {
log.Printf("Starting idle monitoring. System will suspend when:\n")
log.Printf("- Average CPU usage across all cores < %.1f%%\n", cpuThreshold)
log.Printf("- Average GPU usage across all GPUs < %.1f%%\n", gpuThreshold)
if nvmlAvailable {
log.Printf("- Average GPU usage across all GPUs < %.1f%%\n", gpuThreshold)
} else {
log.Printf("- GPU monitoring disabled (NVML initialization failed)")
}
log.Printf("- Disk I/O < %.1f MB/s\n", float64(diskThreshold)/(1024*1024))
log.Printf("- Network I/O < %.1f MB/s\n", float64(networkThreshold)/(1024*1024))
log.Printf("- No active SSH connections\n")
log.Printf("- No active user sessions\n")
log.Printf("Over the last %v\n", monitoringPeriod)
log.Printf("HTTP status endpoint available at http://localhost:%d/status\n", httpPort)
log.Printf("Press Ctrl+C to exit\n")
for range ticker.C {
usage := getCurrentUsage()
usageHistory = append(usageHistory, usage)
mainLoop:
for {
select {
case <-ctx.Done():
break mainLoop
case sig := <-sigChan:
log.Printf("Received signal %v, shutting down...", sig)
cancel()
break mainLoop
case <-ticker.C:
usage := getCurrentUsage()
usageHistory = append(usageHistory, usage)
// Update current status
updateSystemStatus(usage, usageHistory)
// Update current status
updateSystemStatus(usage, usageHistory)
// Remove entries older than monitoring period
cutoff := time.Now().Add(-monitoringPeriod)
for i, u := range usageHistory {
if u.timestamp.After(cutoff) {
usageHistory = usageHistory[i:]
break
// Remove entries older than monitoring period
cutoff := time.Now().Add(-monitoringPeriod)
for i, u := range usageHistory {
if u.Timestamp.After(cutoff) {
usageHistory = usageHistory[i:]
break
}
}
}
if len(usageHistory) > 0 && isSystemIdle(usageHistory) {
log.Printf("System status before suspend:\n")
log.Printf("- CPU: %.1f%%\n", usageHistory[len(usageHistory)-1].cpuUsage)
log.Printf("- GPU: %.1f%%\n", usageHistory[len(usageHistory)-1].gpuUsage)
log.Printf("- SSH connections: %d\n", usageHistory[len(usageHistory)-1].sshConnections)
log.Printf("- Active users: %d\n", usageHistory[len(usageHistory)-1].activeUsers)
log.Println("System has been idle for the monitoring period. Suspending...")
if err := suspendSystem(); err != nil {
log.Printf("Failed to suspend system: %v", err)
if len(usageHistory) > 0 && isSystemIdle(usageHistory) {
log.Printf("System status before suspend:\n")
log.Printf("- CPU: %.1f%%\n", usageHistory[len(usageHistory)-1].CpuUsage)
if nvmlAvailable {
log.Printf("- GPU: %.1f%%\n", usageHistory[len(usageHistory)-1].GpuUsage)
}
log.Printf("- SSH connections: %d\n", usageHistory[len(usageHistory)-1].SshConnections)
log.Printf("- Active users: %d\n", usageHistory[len(usageHistory)-1].ActiveUsers)
log.Println("System has been idle for the monitoring period. Suspending...")
if err := suspendSystem(); err != nil {
log.Printf("Failed to suspend system: %v", err)
}
}
}
}
// Graceful shutdown of HTTP server
shutdownCtx, shutdownCancel := context.WithTimeout(context.Background(), 5*time.Second)
defer shutdownCancel()
if err := srv.Shutdown(shutdownCtx); err != nil {
log.Printf("HTTP server shutdown error: %v", err)
}
log.Println("Goodbye!")
}
func startHTTPServer() {
http.HandleFunc("/status", handleStatus)
if err := http.ListenAndServe(fmt.Sprintf(":%d", httpPort), nil); err != nil {
log.Printf("Failed to start HTTP server: %v", err)
func startHTTPServer(ctx context.Context) *http.Server {
srv := &http.Server{
Addr: fmt.Sprintf(":%d", httpPort),
}
http.HandleFunc("/status", handleStatus)
go func() {
if err := srv.ListenAndServe(); err != http.ErrServerClosed {
log.Printf("HTTP server error: %v", err)
}
}()
return srv
}
func handleStatus(w http.ResponseWriter, r *http.Request) {
@ -132,17 +184,17 @@ func updateSystemStatus(current ResourceUsage, history []ResourceUsage) {
if len(history) >= 2 {
// Calculate rates using last two samples
duration := history[len(history)-1].timestamp.Sub(history[len(history)-2].timestamp).Seconds()
diskIORate := float64(history[len(history)-1].diskIO-history[len(history)-2].diskIO) / duration
netIORate := float64(history[len(history)-1].networkIO-history[len(history)-2].networkIO) / duration
duration := history[len(history)-1].Timestamp.Sub(history[len(history)-2].Timestamp).Seconds()
diskIORate := float64(history[len(history)-1].DiskIO-history[len(history)-2].DiskIO) / duration
netIORate := float64(history[len(history)-1].NetworkIO-history[len(history)-2].NetworkIO) / duration
if current.cpuUsage >= cpuThreshold {
if current.CpuUsage >= cpuThreshold {
currentStatus.Blockers = append(currentStatus.Blockers,
fmt.Sprintf("CPU usage too high: %.1f%% >= %.1f%%", current.cpuUsage, cpuThreshold))
fmt.Sprintf("CPU usage too high: %.1f%% >= %.1f%%", current.CpuUsage, cpuThreshold))
}
if current.gpuUsage >= gpuThreshold {
if nvmlAvailable && current.GpuUsage >= gpuThreshold {
currentStatus.Blockers = append(currentStatus.Blockers,
fmt.Sprintf("GPU usage too high: %.1f%% >= %.1f%%", current.gpuUsage, gpuThreshold))
fmt.Sprintf("GPU usage too high: %.1f%% >= %.1f%%", current.GpuUsage, gpuThreshold))
}
if diskIORate >= float64(diskThreshold) {
currentStatus.Blockers = append(currentStatus.Blockers,
@ -156,13 +208,13 @@ func updateSystemStatus(current ResourceUsage, history []ResourceUsage) {
}
}
if current.sshConnections > 0 {
if current.SshConnections > 0 {
currentStatus.Blockers = append(currentStatus.Blockers,
fmt.Sprintf("Active SSH connections: %d", current.sshConnections))
fmt.Sprintf("Active SSH connections: %d", current.SshConnections))
}
if current.activeUsers > 0 {
if current.ActiveUsers > 0 {
currentStatus.Blockers = append(currentStatus.Blockers,
fmt.Sprintf("Active user sessions: %d", current.activeUsers))
fmt.Sprintf("Active user sessions: %d", current.ActiveUsers))
}
if len(currentStatus.Blockers) == 0 {
@ -172,7 +224,8 @@ func updateSystemStatus(current ResourceUsage, history []ResourceUsage) {
func getCurrentUsage() ResourceUsage {
usage := ResourceUsage{
timestamp: time.Now(),
Timestamp: time.Now(),
GpuAvailable: nvmlAvailable,
}
// Get CPU usage across all cores
@ -182,26 +235,28 @@ func getCurrentUsage() ResourceUsage {
for _, percent := range cpuPercent {
totalCPU += percent
}
usage.cpuUsage = totalCPU / float64(len(cpuPercent))
usage.CpuUsage = totalCPU / float64(len(cpuPercent))
}
// Get GPU usage across all GPUs
count, ret := nvml.DeviceGetCount()
if ret == nvml.SUCCESS && count > 0 {
var totalGPU float64
var activeGPUs int
for i := 0; i < count; i++ {
device, ret := nvml.DeviceGetHandleByIndex(i)
if ret == nvml.SUCCESS {
utilization, ret := device.GetUtilizationRates()
// Get GPU usage across all GPUs if available
if nvmlAvailable {
count, ret := nvml.DeviceGetCount()
if ret == nvml.SUCCESS && count > 0 {
var totalGPU float64
var activeGPUs int
for i := 0; i < count; i++ {
device, ret := nvml.DeviceGetHandleByIndex(i)
if ret == nvml.SUCCESS {
totalGPU += float64(utilization.Gpu)
activeGPUs++
utilization, ret := device.GetUtilizationRates()
if ret == nvml.SUCCESS {
totalGPU += float64(utilization.Gpu)
activeGPUs++
}
}
}
}
if activeGPUs > 0 {
usage.gpuUsage = totalGPU / float64(activeGPUs)
if activeGPUs > 0 {
usage.GpuUsage = totalGPU / float64(activeGPUs)
}
}
}
@ -211,22 +266,22 @@ func getCurrentUsage() ResourceUsage {
for _, stat := range diskStats {
totalIO += stat.ReadBytes + stat.WriteBytes
}
usage.diskIO = totalIO
usage.DiskIO = totalIO
}
// Get network I/O
if netStats, err := net.IOCounters(false); err == nil && len(netStats) > 0 {
usage.networkIO = netStats[0].BytesSent + netStats[0].BytesRecv
usage.NetworkIO = netStats[0].BytesSent + netStats[0].BytesRecv
}
// Count SSH connections
if sshCount, err := getSSHConnectionCount(); err == nil {
usage.sshConnections = sshCount
usage.SshConnections = sshCount
}
// Count active user sessions
if userCount, err := getActiveUserCount(); err == nil {
usage.activeUsers = userCount
usage.ActiveUsers = userCount
}
return usage
@ -286,30 +341,43 @@ func isSystemIdle(history []ResourceUsage) bool {
samples := len(history)
for _, usage := range history {
avgCPU += usage.cpuUsage
avgGPU += usage.gpuUsage
if usage.sshConnections > maxSSHConnections {
maxSSHConnections = usage.sshConnections
avgCPU += usage.CpuUsage
if nvmlAvailable {
avgGPU += usage.GpuUsage
}
if usage.activeUsers > maxActiveUsers {
maxActiveUsers = usage.activeUsers
if usage.SshConnections > maxSSHConnections {
maxSSHConnections = usage.SshConnections
}
if usage.ActiveUsers > maxActiveUsers {
maxActiveUsers = usage.ActiveUsers
}
}
// Calculate I/O rates using first and last samples
duration := history[samples-1].timestamp.Sub(history[0].timestamp).Seconds()
diskIORate := float64(history[samples-1].diskIO-history[0].diskIO) / duration
netIORate := float64(history[samples-1].networkIO-history[0].networkIO) / duration
duration := history[samples-1].Timestamp.Sub(history[0].Timestamp).Seconds()
diskIORate := float64(history[samples-1].DiskIO-history[0].DiskIO) / duration
netIORate := float64(history[samples-1].NetworkIO-history[0].NetworkIO) / duration
avgCPU /= float64(samples)
avgGPU /= float64(samples)
if nvmlAvailable {
avgGPU /= float64(samples)
}
return avgCPU < cpuThreshold &&
avgGPU < gpuThreshold &&
diskIORate < float64(diskThreshold) &&
netIORate < float64(networkThreshold) &&
maxSSHConnections == 0 &&
maxActiveUsers == 0
// Basic checks that always apply
if avgCPU >= cpuThreshold ||
diskIORate >= float64(diskThreshold) ||
netIORate >= float64(networkThreshold) ||
maxSSHConnections > 0 ||
maxActiveUsers > 0 {
return false
}
// GPU check only if NVML is available
if nvmlAvailable && avgGPU >= gpuThreshold {
return false
}
return true
}
func suspendSystem() error {