Properly setting the metadata cache size can provide better performance
in case of using big qcow2 images.
This patch introduces two driver options:
* driver.metadata_cache.max_size
* driver.metadata_cache.max_size.unit
E.g. --disk ...,driver.type=qcow2,\
driver.metadata_cache.max_size=2,\
driver.metadata_cache.max_size.unit=MiB
BTW, Metadata cache size control is currently supported only for qcow2.
Regarding how to properly caluclate the cache size of qcow2, Please refer
to qemu's documentation.
Signed-off-by: Lin Ma <lma@xxxxxxxx>
---
tests/data/cli/compare/virt-install-many-devices.xml | 9 +++++++++
tests/test_cli.py | 1 +
virtinst/cli.py | 7 +++++++
virtinst/devices/disk.py | 5 +++++
4 files changed, 22 insertions(+)
diff --git a/tests/data/cli/compare/virt-install-many-devices.xml b/tests/data/cli/compare/virt-install-many-devices.xml
index a73343a9..a33dc16a 100644
--- a/tests/data/cli/compare/virt-install-many-devices.xml
+++ b/tests/data/cli/compare/virt-install-many-devices.xml
@@ -423,6 +423,15 @@
</source>
<target dev="vdu" bus="virtio"/>
</disk>
+ <disk type="file" device="disk">
+ <driver name="qemu" type="qcow2">
+ <metadata_cache>
+ <max_size unit="KiB">2048</max_size>
+ </metadata_cache>
+ </driver>
+ <source file="/tmp/disk1.qcow2"/>
+ <target dev="vdv" bus="virtio"/>
+ </disk>
<controller type="usb" index="0" model="ich9-ehci1">
<address type="pci" domain="0" bus="0" slot="4" function="7"/>
</controller>
diff --git a/tests/test_cli.py b/tests/test_cli.py
index 774db098..259ac78c 100644
--- a/tests/test_cli.py
+++ b/tests/test_cli.py
@@ -605,6 +605,7 @@ source.reservations.managed=no,source.reservations.source.type=unix,source.reser
--disk path=/fooroot.img,size=.0001,transient=on
--disk source.dir=/
--disk type=nvme,source.type=pci,source.managed=no,source.namespace=2,source.address.domain=0x0001,source.address.bus=0x02,source.address.slot=0x00,source.address.function=0x0
+--disk /tmp/disk1.qcow2,size=16,driver.type=qcow2,driver.metadata_cache.max_size=2048,driver.metadata_cache.max_size.unit=KiB
--network user,mac=12:34:56:78:11:22,portgroup=foo,link_state=down,rom_bar=on,rom_file=/tmp/foo
diff --git a/virtinst/cli.py b/virtinst/cli.py
index c4dffd34..042b500f 100644
--- a/virtinst/cli.py
+++ b/virtinst/cli.py
@@ -3497,6 +3497,8 @@ class ParserDisk(VirtCLIParser):
"driver.io": "io",
"driver.name": "driver_name",
"driver.type": "driver_type",
+ "driver.metadata_cache.max_size": "metadata_cache.max_size",
+ "driver.metadata_cache.max_size.unit": "metadata_cache.max_size.unit",
}
def _add_advertised_aliases(self):
@@ -3696,6 +3698,11 @@ class ParserDisk(VirtCLIParser):
cls.add_arg("driver.queues", "driver_queues")
cls.add_arg("driver.error_policy", "error_policy")
+ cls.add_arg("driver.metadata_cache.max_size",
+ "driver_metadata_cache_max_size")
+ cls.add_arg("driver.metadata_cache.max_size.unit",
+ "driver_metadata_cache_max_size_unit")
+
cls.add_arg("iotune.read_bytes_sec", "iotune_rbs")
cls.add_arg("iotune.write_bytes_sec", "iotune_wbs")
cls.add_arg("iotune.total_bytes_sec", "iotune_tbs")
diff --git a/virtinst/devices/disk.py b/virtinst/devices/disk.py
index dc59fd13..9609ebac 100644
--- a/virtinst/devices/disk.py
+++ b/virtinst/devices/disk.py
@@ -481,6 +481,11 @@ class DeviceDisk(Device):
driver_iothread = XMLProperty("./driver/@iothread", is_int=True)
driver_queues = XMLProperty("./driver/@queues", is_int=True)
+ driver_metadata_cache_max_size = XMLProperty(
+ "./driver/metadata_cache/max_size", is_int=True)
+ driver_metadata_cache_max_size_unit = XMLProperty(
+ "./driver/metadata_cache/max_size/@unit")
+
error_policy = XMLProperty("./driver/@error_policy")
serial = XMLProperty("./serial")
wwn = XMLProperty("./wwn")
--
2.26.2
