mirror of
https://gitlab.com/libvirt/libvirt.git
synced 2024-11-03 20:01:16 +00:00
bf14a9be1e
Currently, we configure QEMU to prealloc memory almost by
default. Well, by default for NVDIMMs, hugepages and if user
asked us to (via memoryBacking <allocation mode="immediate"/>).
However, when guest's NVDIMM is backed by real life NVDIMM this
approach is not the best. In this case users should put <pmem/>
into the <memory/> device <source/>, like this:
<memory model='nvdimm' access='shared'>
<source>
<path>/dev/pmem0</path>
<pmem/>
</source>
</memory>
Instructing QEMU to do prealloc in this case means that each
page of the NVDIMM is "touched" (the first byte is read and
written back - see QEMU commit v2.9.0-rc1~26^2) which cripples
device wear.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1894053
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
45 lines
1.7 KiB
Plaintext
45 lines
1.7 KiB
Plaintext
LC_ALL=C \
|
|
PATH=/bin \
|
|
HOME=/tmp/lib/domain--1-QEMUGuest1 \
|
|
USER=test \
|
|
LOGNAME=test \
|
|
XDG_DATA_HOME=/tmp/lib/domain--1-QEMUGuest1/.local/share \
|
|
XDG_CACHE_HOME=/tmp/lib/domain--1-QEMUGuest1/.cache \
|
|
XDG_CONFIG_HOME=/tmp/lib/domain--1-QEMUGuest1/.config \
|
|
QEMU_AUDIO_DRV=none \
|
|
/usr/bin/qemu-system-i386 \
|
|
-name guest=QEMUGuest1,debug-threads=on \
|
|
-S \
|
|
-object secret,id=masterKey0,format=raw,\
|
|
file=/tmp/lib/domain--1-QEMUGuest1/master-key.aes \
|
|
-machine pc,accel=tcg,usb=off,dump-guest-core=off,nvdimm=on \
|
|
-cpu qemu64 \
|
|
-m size=219136k,slots=16,maxmem=1099511627776k \
|
|
-overcommit mem-lock=off \
|
|
-smp 2,sockets=2,dies=1,cores=1,threads=1 \
|
|
-object memory-backend-ram,id=ram-node0,size=224395264 \
|
|
-numa node,nodeid=0,cpus=0-1,memdev=ram-node0 \
|
|
-object memory-backend-file,id=memnvdimm0,mem-path=/tmp/nvdimm,share=no,\
|
|
size=536870912,pmem=yes \
|
|
-device nvdimm,node=0,memdev=memnvdimm0,id=nvdimm0,slot=0 \
|
|
-uuid c7a5fdbd-edaf-9455-926a-d65c16db1809 \
|
|
-display none \
|
|
-no-user-config \
|
|
-nodefaults \
|
|
-chardev socket,id=charmonitor,fd=1729,server,nowait \
|
|
-mon chardev=charmonitor,id=monitor,mode=control \
|
|
-rtc base=utc \
|
|
-no-shutdown \
|
|
-no-acpi \
|
|
-boot strict=on \
|
|
-device piix3-usb-uhci,id=usb,bus=pci.0,addr=0x1.0x2 \
|
|
-blockdev '{"driver":"host_device","filename":"/dev/HostVG/QEMUGuest1",\
|
|
"node-name":"libvirt-1-storage","auto-read-only":true,"discard":"unmap"}' \
|
|
-blockdev '{"node-name":"libvirt-1-format","read-only":false,"driver":"raw",\
|
|
"file":"libvirt-1-storage"}' \
|
|
-device ide-hd,bus=ide.0,unit=0,drive=libvirt-1-format,id=ide0-0-0,bootindex=1 \
|
|
-device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x3 \
|
|
-sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,\
|
|
resourcecontrol=deny \
|
|
-msg timestamp=on
|