From 1b781271d6c08aeb49eb0a8c3254ed2ce3f107b1 Mon Sep 17 00:00:00 2001
From: Jan Kaluza <hanzz.k@gmail.com>
Date: Tue, 17 Apr 2012 10:23:59 +0200
Subject: [PATCH] readahead_multiplier

---
 tuned/plugins/plugin_disk.py | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/tuned/plugins/plugin_disk.py b/tuned/plugins/plugin_disk.py
index 5f064f2..0f53458 100644
--- a/tuned/plugins/plugin_disk.py
+++ b/tuned/plugins/plugin_disk.py
@@ -52,6 +52,8 @@ class DiskPlugin(tuned.plugins.Plugin):
 			"elevator"   : "",
 			"disk_alpm"  : "",
 			"disk_apm"  : "",
+			"disk_spindown"  : "",
+			"disk_readahead_multiplier" : "",
 		}
 
 	def _update_idle(self, dev):
@@ -101,6 +103,7 @@ class DiskPlugin(tuned.plugins.Plugin):
 				os.system("hdparm -S0 -B255 /dev/"+dev+" > /dev/null 2>&1")
 			self._revert_elevator(dev)
 			self._revert_disk_apm(dev)
+			self._revert_disk_readahead_multiplier(dev)
 
 		self._revert_disk_alpm()
 
@@ -110,6 +113,8 @@ class DiskPlugin(tuned.plugins.Plugin):
 			if not self._elevator_set:
 				self._apply_elevator(dev)
 				self._apply_disk_apm(dev)
+				self._apply_disk_spindown(dev)
+				self._apply_disk_readahead_multiplier(dev)
 
 			self._init_stats(dev)
 			self._update_stats(dev, devload)
@@ -205,4 +210,33 @@ class DiskPlugin(tuned.plugins.Plugin):
 		if storage.data["disk"].has_key("disk_apm_" + dev):
 			tuned.utils.commands.execute(["hdparm", "-B", storage.data["disk"]["disk_apm_" + dev], "/dev/" + dev])
 			del storage.data["disk"]["disk_apm_" + dev]
+
+	def _apply_disk_spindown(self, dev):
+		if len(self._options["disk_spindown"]) == 0:
+			return False
+
+		tuned.utils.commands.execute(["hdparm", "-S", self._options["disk_spindown"], "/dev/" + dev])
+		return True
+
+	def _apply_disk_readahead_multiplier(self, dev):
+		self._revert_elevator(dev)
+
+		if len(self._options["elevator"]) == 0:
+			return False
+
+		sys_file = os.path.join("/sys/block/", dev, "queue/read_ahead_kb")
+		try:
+			value = open(sys_file).read().strip()
+		except (OSError,IOError) as e:
+			log.error("Reading %s error: %s" % (sys_file, e))
+			return
+
+		new_value = int(int(value) * float(self._options["disk_readahead_multiplier"]))
 		
+		tuned.utils.commands.set_file("disk", "disk_readahead_multiplier_" + dev, sys_file, str(new_value))
+		return True
+
+	def _revert_disk_readahead_multiplier(self, dev):
+		sys_file = os.path.join("/sys/block/", dev, "queue/read_ahead_kb")
+		tuned.utils.commands.revert_file("disk", "disk_readahead_multiplier_" + dev, sys_file)
+