adding memstat option to server

diff --git a/commands/server.go b/commands/server.go
index c80440c5cdac9c5fa2c9a756fb1056654f5248c0..ee30b927551f93d9653fe0704d353371813c5171 100644 (file)
--- a/commands/server.go
+++ b/commands/server.go
@@ -1,4 +1,4 @@
-// Copyright © 2013 Steve Francia <spf@spf13.com>.
+// Copyright © 2013-14 Steve Francia <spf@spf13.com>.
 //
 // Licensed under the Simple Public License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
@@ -19,8 +19,10 @@ import (
        "net/http"
        "net/url"
        "os"
+       "runtime"
        "strconv"
        "strings"
+       "time"
 
        "github.com/spf13/cobra"
        "github.com/spf13/hugo/helpers"
@@ -49,6 +51,8 @@ func init() {
        serverCmd.Flags().BoolVarP(&serverWatch, "watch", "w", false, "watch filesystem for changes and recreate as needed")
        serverCmd.Flags().BoolVarP(&serverAppend, "appendPort", "", true, "append port to baseurl")
        serverCmd.Flags().BoolVar(&disableLiveReload, "disableLiveReload", false, "watch without enabling live browser reload on rebuild")
+       serverCmd.Flags().String("memstats", "", "log memory usage to this file")
+       serverCmd.Flags().Int("meminterval", 100, "interval to poll memory usage (requires --memstats)")
        serverCmd.Run = server
 }
 
@@ -84,6 +88,10 @@ func server(cmd *cobra.Command, args []string) {
        }
        viper.Set("BaseUrl", BaseUrl)
 
+       if err := memStats(); err != nil {
+               jww.ERROR.Println("memstats error:", err)
+       }
+
        build(serverWatch)
 
        // Watch runs its own server as part of the routine
@@ -157,3 +165,38 @@ func fixUrl(s string) (string, error) {
        }
        return u.String(), nil
 }
+
+func memStats() error {
+       memstats := serverCmd.Flags().Lookup("memstats").Value.String()
+       if memstats != "" {
+               interval, err := time.ParseDuration(serverCmd.Flags().Lookup("meminterval").Value.String())
+               if err != nil {
+                       interval, _ = time.ParseDuration("100ms")
+               }
+
+               fileMemStats, err := os.Create(memstats)
+               if err != nil {
+                       return err
+               }
+
+               fileMemStats.WriteString("# Time\tHeapSys\tHeapAlloc\tHeapIdle\tHeapReleased\n")
+
+               go func() {
+                       var stats runtime.MemStats
+
+                       start := time.Now().UnixNano()
+
+                       for {
+                               runtime.ReadMemStats(&stats)
+                               if fileMemStats != nil {
+                                       fileMemStats.WriteString(fmt.Sprintf("%d\t%d\t%d\t%d\t%d\n",
+                                               (time.Now().UnixNano()-start)/1000000, stats.HeapSys, stats.HeapAlloc, stats.HeapIdle, stats.HeapReleased))
+                                       time.Sleep(interval)
+                               } else {
+                                       break
+                               }
+                       }
+               }()
+       }
+       return nil
+}