diff options
| author | Zhu Guihua <zhugh.fnst@cn.fujitsu.com> | 2015-04-27 16:47:15 +0800 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2015-04-27 21:07:38 +0200 |
| commit | 4fccb4834d0455519ff6d7a81551a8dfd360fefa (patch) | |
| tree | 2237d659cf579075ebecd103516af3a989e0d87e /docs/memory-hotplug.txt | |
| parent | 850d00700ba787988b6c5404e8c1a3add7141db1 (diff) | |
docs: update documentation for memory hot unplug
Add specification about how to use memory hot unplug, and add
a flow diagram to explain memory hot unplug process.
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: Zhu Guihua <zhugh.fnst@cn.fujitsu.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'docs/memory-hotplug.txt')
| -rw-r--r-- | docs/memory-hotplug.txt | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/docs/memory-hotplug.txt b/docs/memory-hotplug.txt index f70571df0c..56bdd0a47b 100644 --- a/docs/memory-hotplug.txt +++ b/docs/memory-hotplug.txt @@ -4,9 +4,7 @@ QEMU memory hotplug This document explains how to use the memory hotplug feature in QEMU, which is present since v2.1.0. -Please, note that memory hotunplug is not supported yet. This means -that you're able to add memory, but you're not able to remove it. -Also, proper guest support is required for memory hotplug to work. +Guest support is required for memory hotplug to work. Basic RAM hotplug ----------------- @@ -74,3 +72,22 @@ comes from regular RAM, 1GB is a 1GB hugepage page and 256MB is from -device pc-dimm,id=dimm1,memdev=mem1 \ -object memory-backend-file,id=mem2,size=256M,mem-path=/mnt/hugepages-2MB \ -device pc-dimm,id=dimm2,memdev=mem2 + + +RAM hot-unplug +--------------- + +In order to be able to hot unplug pc-dimm device, QEMU has to be told the ids +of pc-dimm device and memory backend object. The ids were assigned when you hot +plugged memory. + +Two monitor commands are used to hot unplug memory: + + - "device_del": deletes a front-end pc-dimm device + - "object_del": deletes a memory backend object + +For example, assuming that the pc-dimm device with id "dimm1" exists, and its memory +backend is "mem1", the following commands tries to remove it. + + (qemu) device_del dimm1 + (qemu) object_del mem1 |