The options specifies metadata cache size policy for a disk.
This is going to be used only for QEMU and only for qcow2 images in
next patch to set qcow2 L2 cache size.
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy(a)virtuozzo.com>
---
docs/formatdomain.html.in | 11 ++++++
docs/schemas/domaincommon.rng | 11 ++++++
src/conf/domain_conf.c | 17 +++++++++
src/conf/domain_conf.h | 9 +++++
.../qemuxml2argvdata/disk-metadata_cache_size.xml | 35 ++++++++++++++++++
.../disk-metadata_cache_size.xml | 41 ++++++++++++++++++++++
tests/qemuxml2xmltest.c | 2 ++
7 files changed, 126 insertions(+)
create mode 100644 tests/qemuxml2argvdata/disk-metadata_cache_size.xml
create mode 100644 tests/qemuxml2xmloutdata/disk-metadata_cache_size.xml
diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
index 7f07bb7..fcffa9c 100644
--- a/docs/formatdomain.html.in
+++ b/docs/formatdomain.html.in
@@ -3608,6 +3608,17 @@
virt queues for virtio-blk. (<span class="since">Since
3.9.0</span>)
</li>
<li>
+ The optional <code>metadata_cache_size</code> attribute
specifies
+ metadata cache size policy. Possible values are "default" and
+ "maximum". Using "default" leaves setting cache size to
the hypervisor,
+ Using "maximum" ensures entire disk cache remains in memory,
increasing
+ IO but utilizing more memory. This policy helps if workload's
+ disk working set (the amount of disk data used intensively) is too large
+ to be covered by cache size by "default" policy.
+ (<span class="since">Since 5.0.0, QEMU 3.0</span>). The
option makes
+ sense only for non raw images and supported for qcow2 only now.
+ </li>
+ <li>
For virtio disks,
<a href="#elementsVirtio">Virtio-specific options</a> can
also be
set. (<span class="since">Since 3.5.0</span>)
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index aa50eac..aa8b8ff 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -2003,6 +2003,9 @@
<ref name="detect_zeroes"/>
</optional>
<optional>
+ <ref name="metadata_cache_size"/>
+ </optional>
+ <optional>
<attribute name='queues'>
<ref name="positiveInteger"/>
</attribute>
@@ -2103,6 +2106,14 @@
</choice>
</attribute>
</define>
+ <define name="metadata_cache_size">
+ <attribute name='metadata_cache_size'>
+ <choice>
+ <value>default</value>
+ <value>maximum</value>
+ </choice>
+ </attribute>
+ </define>
<define name="controller">
<element name="controller">
<optional>
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 222bb8c..9488c35 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -889,6 +889,11 @@ VIR_ENUM_IMPL(virDomainDiskDetectZeroes,
VIR_DOMAIN_DISK_DETECT_ZEROES_LAST,
"on",
"unmap")
+VIR_ENUM_IMPL(virDomainDiskMetadataCacheSize,
+ VIR_DOMAIN_DISK_METADATA_CACHE_SIZE_LAST,
+ "default",
+ "maximum")
+
VIR_ENUM_IMPL(virDomainDiskMirrorState, VIR_DOMAIN_DISK_MIRROR_STATE_LAST,
"none",
"yes",
@@ -9419,6 +9424,14 @@ virDomainDiskDefDriverParseXML(virDomainDiskDefPtr def,
}
VIR_FREE(tmp);
+ if ((tmp = virXMLPropString(cur, "metadata_cache_size")) &&
+ (def->metadata_cache_size = virDomainDiskMetadataCacheSizeTypeFromString(tmp))
< 0) {
+ virReportError(VIR_ERR_CONFIG_UNSUPPORTED,
+ _("unknown driver metadata_cache_size value
'%s'"), tmp);
+ goto cleanup;
+ }
+ VIR_FREE(tmp);
+
ret = 0;
cleanup:
@@ -24193,6 +24206,10 @@ virDomainDiskDefFormatDriver(virBufferPtr buf,
if (disk->queues)
virBufferAsprintf(&driverBuf, " queues='%u'",
disk->queues);
+ if (disk->metadata_cache_size)
+ virBufferAsprintf(&driverBuf, " metadata_cache_size='%s'",
+
virDomainDiskMetadataCacheSizeTypeToString(disk->metadata_cache_size));
+
virDomainVirtioOptionsFormat(&driverBuf, disk->virtio);
return virXMLFormatElement(buf, "driver", &driverBuf, NULL);
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index fae1306..31ce9ab 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -567,6 +567,13 @@ typedef enum {
VIR_DOMAIN_DISK_DETECT_ZEROES_LAST
} virDomainDiskDetectZeroes;
+typedef enum {
+ VIR_DOMAIN_DISK_METADATA_CACHE_SIZE_DEFAULT = 0,
+ VIR_DOMAIN_DISK_METADATA_CACHE_SIZE_MAXIMUM,
+
+ VIR_DOMAIN_DISK_METADATA_CACHE_SIZE_LAST
+} virDomainDiskMetadataCacheSize;
+
typedef struct _virDomainBlockIoTuneInfo virDomainBlockIoTuneInfo;
struct _virDomainBlockIoTuneInfo {
unsigned long long total_bytes_sec;
@@ -672,6 +679,7 @@ struct _virDomainDiskDef {
int discard; /* enum virDomainDiskDiscard */
unsigned int iothread; /* unused = 0, > 0 specific thread # */
int detect_zeroes; /* enum virDomainDiskDetectZeroes */
+ int metadata_cache_size; /* enum virDomainDiskMetadataCacheSize */
char *domain_name; /* backend domain name */
unsigned int queues;
virDomainVirtioOptionsPtr virtio;
@@ -3408,6 +3416,7 @@ VIR_ENUM_DECL(virDomainDeviceSGIO)
VIR_ENUM_DECL(virDomainDiskTray)
VIR_ENUM_DECL(virDomainDiskDiscard)
VIR_ENUM_DECL(virDomainDiskDetectZeroes)
+VIR_ENUM_DECL(virDomainDiskMetadataCacheSize)
VIR_ENUM_DECL(virDomainDiskMirrorState)
VIR_ENUM_DECL(virDomainController)
VIR_ENUM_DECL(virDomainControllerModelPCI)
diff --git a/tests/qemuxml2argvdata/disk-metadata_cache_size.xml
b/tests/qemuxml2argvdata/disk-metadata_cache_size.xml
new file mode 100644
index 0000000..121171a
--- /dev/null
+++ b/tests/qemuxml2argvdata/disk-metadata_cache_size.xml
@@ -0,0 +1,35 @@
+<domain type='qemu'>
+ <name>test</name>
+ <uuid>468404ad-d49c-40f2-9e14-02294f9c1be3</uuid>
+ <memory unit='KiB'>1048576</memory>
+ <currentMemory unit='KiB'>1048576</currentMemory>
+ <vcpu placement='static'>1</vcpu>
+ <os>
+ <type arch='x86_64' machine='pc'>hvm</type>
+ <boot dev='cdrom'/>
+ <boot dev='hd'/>
+ <bootmenu enable='yes'/>
+ </os>
+ <clock offset='utc'/>
+ <on_poweroff>destroy</on_poweroff>
+ <on_reboot>restart</on_reboot>
+ <on_crash>restart</on_crash>
+ <devices>
+ <emulator>/usr/bin/qemu-system-x86_64</emulator>
+ <disk type='file' device='disk'>
+ <driver name='qemu' type='qcow2'
metadata_cache_size='maximum'/>
+ <source file='/var/lib/libvirt/images/f14.img'/>
+ <target dev='vda' bus='virtio'/>
+ <address type='pci' domain='0x0000' bus='0x00'
slot='0x04' function='0x0'/>
+ </disk>
+ <controller type='usb' index='0'/>
+ <controller type='virtio-serial' index='0'>
+ <address type='pci' domain='0x0000' bus='0x00'
slot='0x06' function='0x0'/>
+ </controller>
+ <controller type='ide' index='0'/>
+ <controller type='pci' index='0' model='pci-root'/>
+ <input type='mouse' bus='ps2'/>
+ <input type='keyboard' bus='ps2'/>
+ <memballoon model='virtio'/>
+ </devices>
+</domain>
diff --git a/tests/qemuxml2xmloutdata/disk-metadata_cache_size.xml
b/tests/qemuxml2xmloutdata/disk-metadata_cache_size.xml
new file mode 100644
index 0000000..2ca7dc4
--- /dev/null
+++ b/tests/qemuxml2xmloutdata/disk-metadata_cache_size.xml
@@ -0,0 +1,41 @@
+<domain type='qemu'>
+ <name>test</name>
+ <uuid>468404ad-d49c-40f2-9e14-02294f9c1be3</uuid>
+ <memory unit='KiB'>1048576</memory>
+ <currentMemory unit='KiB'>1048576</currentMemory>
+ <vcpu placement='static'>1</vcpu>
+ <os>
+ <type arch='x86_64' machine='pc'>hvm</type>
+ <boot dev='cdrom'/>
+ <boot dev='hd'/>
+ <bootmenu enable='yes'/>
+ </os>
+ <clock offset='utc'/>
+ <on_poweroff>destroy</on_poweroff>
+ <on_reboot>restart</on_reboot>
+ <on_crash>restart</on_crash>
+ <devices>
+ <emulator>/usr/bin/qemu-system-x86_64</emulator>
+ <disk type='file' device='disk'>
+ <driver name='qemu' type='qcow2'
metadata_cache_size='maximum'/>
+ <source file='/var/lib/libvirt/images/f14.img'/>
+ <target dev='vda' bus='virtio'/>
+ <address type='pci' domain='0x0000' bus='0x00'
slot='0x04' function='0x0'/>
+ </disk>
+ <controller type='usb' index='0'>
+ <address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x2'/>
+ </controller>
+ <controller type='virtio-serial' index='0'>
+ <address type='pci' domain='0x0000' bus='0x00'
slot='0x06' function='0x0'/>
+ </controller>
+ <controller type='ide' index='0'>
+ <address type='pci' domain='0x0000' bus='0x00'
slot='0x01' function='0x1'/>
+ </controller>
+ <controller type='pci' index='0' model='pci-root'/>
+ <input type='mouse' bus='ps2'/>
+ <input type='keyboard' bus='ps2'/>
+ <memballoon model='virtio'>
+ <address type='pci' domain='0x0000' bus='0x00'
slot='0x03' function='0x0'/>
+ </memballoon>
+ </devices>
+</domain>
diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c
index 82e2c0e..4aa845c 100644
--- a/tests/qemuxml2xmltest.c
+++ b/tests/qemuxml2xmltest.c
@@ -1265,6 +1265,8 @@ mymain(void)
DO_TEST("riscv64-virt",
QEMU_CAPS_DEVICE_VIRTIO_MMIO);
+ DO_TEST("disk-metadata_cache_size", NONE);
+
if (getenv("LIBVIRT_SKIP_CLEANUP") == NULL)
virFileDeleteTree(fakerootdir);
--
1.8.3.1