From 1a80a7173566cbd58086be880574b7d3261faff7 Mon Sep 17 00:00:00 2001
From: Kuo-tung Kao <jelly.k@inwinstack.com>
Date: Thu, 25 Jun 2015 10:43:32 +0800
Subject: [PATCH] Add Nova Scheduler IO Ops Weighter

Add a new nova scheduler weighter, sort the filter
hosts according to host io ops number, aims to
instances on light workload hosts.

Change-Id: I6b9a87c3ea3c6979d04f51eb082e14acc0334c5f
Closes-Bug: #1383178
---
 .../compute/section_compute-scheduler.xml                 | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/doc/config-reference/compute/section_compute-scheduler.xml b/doc/config-reference/compute/section_compute-scheduler.xml
index 8b8ecf7eb6..415005bc74 100644
--- a/doc/config-reference/compute/section_compute-scheduler.xml
+++ b/doc/config-reference/compute/section_compute-scheduler.xml
@@ -883,6 +883,13 @@ isolated_images = 342b492c-128f-4a42-8d3a-c5088cf27d13, ebd267a6-ca86-4d6c-9a0e-
                         RamWeigher and MetricsWeigher. Hosts are then weighted and sorted
                         with the largest weight winning.</td>
                 </tr>
+                <tr valign="top">
+                    <td>[DEFAULT]</td>
+                    <td><literal>io_ops_weight_multiplier</literal></td>
+                    <td>Multiplier used for weighing host I/O operations. A negative
+                        value means a preference to choose light workload
+                        compute hosts.</td>
+                </tr>
                 <tr valign="top">
                     <td>[metrics]</td>
                     <td><literal>weight_multiplier</literal></td>
@@ -938,6 +945,7 @@ isolated_images = 342b492c-128f-4a42-8d3a-c5088cf27d13, ebd267a6-ca86-4d6c-9a0e-
 scheduler_host_subset_size = 1
 scheduler_weight_classes = nova.scheduler.weights.all_weighers
 ram_weight_multiplier = 1.0
+io_ops_weight_multiplier = 2.0
 [metrics]
 weight_multiplier = 1.0
 weight_setting = name1=1.0, name2=-1.0