[PATCH 3/4] nfs-utils: nfs-iostat.py autofs cleanup and option to sort by ops/s

[Lans Carstensen <Lans.Carstensen@dreamworks.com>]

commit ef558b7b978418ac3da35e36dcf02a223e4ebe2d
Author: Lans Carstensen <Lans.Carstensen@dreamworks.com>
Date:   Tue Aug 25 21:52:49 2009 -0700

     Update list of mount points to parse stats for and drop mount
     points from stats collection when they are umounted.  This
     ensures proper stats collection for autofs mountpoints.

diff --git a/tools/nfs-iostat/nfs-iostat.py b/tools/nfs-iostat/nfs-iostat.py
index 6ce31fc..9f3b3eb 100644
--- a/tools/nfs-iostat/nfs-iostat.py
+++ b/tools/nfs-iostat/nfs-iostat.py
@@ -447,7 +447,14 @@ def parse_stats_file(filename):
      return ms_dict

  def print_iostat_summary(old, new, devices, time, ac):
-    for device in devices:
+    if old:
+        # Trim device list to only include intersection of old and new 
data,
+        # this addresses umounts due to autofs mountpoints
+        devicelist = filter(lambda x:x in devices,old)
+    else:
+        devicelist = devices
+
+    for device in devicelist:
          stats = DeviceData()
          stats.parse_stats(new[device])
          if not old:
@@ -458,11 +465,35 @@ def print_iostat_summary(old, new, devices, time, ac):
              diff_stats = stats.compare_iostats(old_stats)
              diff_stats.display_iostats(time, ac)

+def list_nfs_mounts(givenlist, mountstats):
+    """return a list of NFS mounts given a list to validate or
+       return a full list if the given list is empty
+    """
+    list = []
+    if len(givenlist) > 0:
+        for device in givenlist:
+            stats = DeviceData()
+            stats.parse_stats(mountstats[device])
+            if stats.is_nfs_mountpoint():
+                list += [device]
+    else:
+        for device, descr in mountstats.iteritems():
+            stats = DeviceData()
+            stats.parse_stats(descr)
+            if stats.is_nfs_mountpoint():
+                list += [device]
+    if len(list) == 0:
+        print 'No NFS mount points were found'
+        return
+
+    return list
+
  def iostat_command(name):
      """iostat-like command for NFS mount points
      """
      mountstats = parse_stats_file('/proc/self/mountstats')
      devices = []
+    origdevices = []
      which = 0
      interval_seen = False
      count_seen = False
@@ -492,7 +523,7 @@ def iostat_command(name):
              continue

          if arg in mountstats:
-            devices += [arg]
+            origdevices += [arg]
          elif not interval_seen:
              interval = int(arg)
              if interval > 0:
@@ -509,23 +540,7 @@ def iostat_command(name):
                  return

      # make certain devices contains only NFS mount points
-    if len(devices) > 0:
-        check = []
-        for device in devices:
-            stats = DeviceData()
-            stats.parse_stats(mountstats[device])
-            if stats.is_nfs_mountpoint():
-                check += [device]
-        devices = check
-    else:
-        for device, descr in mountstats.iteritems():
-            stats = DeviceData()
-            stats.parse_stats(descr)
-            if stats.is_nfs_mountpoint():
-                devices += [device]
-    if len(devices) == 0:
-        print 'No NFS mount points were found'
-        return
+    devices = list_nfs_mounts(origdevices, mountstats)

      old_mountstats = None
      sample_time = 0.0
@@ -541,6 +556,9 @@ def iostat_command(name):
              time.sleep(interval)
              sample_time = interval
              mountstats = parse_stats_file('/proc/self/mountstats')
+            # automount mountpoints add and drop, if automount is involved
+            # we need to recheck the devices list when reparsing
+            devices = list_nfs_mounts(origdevices,mountstats)
              count -= 1
      else:
          while True:
@@ -549,6 +567,9 @@ def iostat_command(name):
              time.sleep(interval)
              sample_time = interval
              mountstats = parse_stats_file('/proc/self/mountstats')
+            # automount mountpoints add and drop, if automount is involved
+            # we need to recheck the devices list when reparsing
+            devices = list_nfs_mounts(origdevices,mountstats)

  #
  # Main