Random write IOPS will drop dramatically if qcow2 l2 cache could not cover the whole disk. This patch gives libvirt user a chance to adjust the qcow2 cache configuration. Three new qcow2 driver paramters are added. They are l2-cache-size, refcount-cache-size and cache-clean-interval. The following are from qcow2-cache.txt. The amount of virtual disk that can be mapped by the L2 and refcount caches (in bytes) is: disk_size = l2_cache_size * cluster_size / 8 disk_size = refcount_cache_size * cluster_size * 8 / refcount_bits The parameter "cache-clean-interval" defines an interval (in seconds). All cache entries that haven't been accessed during that interval are removed from memory. Signed-off-by: Liu Qing <liuqing(a)huayun.com&gt; --- docs/formatdomain.html.in | 21 +++++++++++ docs/schemas/domaincommon.rng | 24 +++++++++++++ src/conf/domain_conf.c | 30 ++++++++++++++++ src/qemu/qemu_command.c | 6 ++++ src/util/virstoragefile.c | 3 ++ src/util/virstoragefile.h | 4 +++ ...2argv-disk-drive-qcow2-cache-clean-interval.xml | 37 +++++++++++++++++++ ...qemuxml2argv-disk-drive-qcow2-l2-cache-size.xml | 37 +++++++++++++++++++ ...l2argv-disk-drive-qcow2-refcount-cache-size.xml | 37 +++++++++++++++++++ ...mlout-disk-drive-qcow2-cache-clean-interval.xml | 41 ++++++++++++++++++++++ ...muxml2xmlout-disk-drive-qcow2-l2-cache-size.xml | 41 ++++++++++++++++++++++ ...xmlout-disk-drive-qcow2-refcount-cache-size.xml | 41 ++++++++++++++++++++++ tests/qemuxml2xmltest.c | 3 ++ 13 files changed, 325 insertions(+) create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-drive-qcow2-cache-clean-interval.xml create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-drive-qcow2-l2-cache-size.xml create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-drive-qcow2-refcount-cache-size.xml create mode 100644 tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-qcow2-cache-clean-interval.xml create mode 100644 tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-qcow2-l2-cache-size.xml create mode 100644 tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-qcow2-refcount-cache-size.xml diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in index 8ca7637..8f093b5 100644 --- a/docs/formatdomain.html.in +++ b/docs/formatdomain.html.in @@ -3035,6 +3035,27 @@ <a href="#elementsVirtio">Virtio-specific options</a> can also be set. (<span class="since">Since 3.5.0</span>) </li> + <li> + The optional <code>l2_cache_size</code> attribute controls how much + memory will be consumed by qcow2 l2 table cache. This option is + only valid when the driver type is qcow2. The default size is 1MB. + <span class='since'>Since 3.7.0</span> + </li> + <li> + The optional <code>refcount_cache_size</code> attribute controls + how much memory will be consumed by qcow2 reference count table + cache. This option is only valid when the driver type is qcow2. + The default size is 256KB. + <span class='since'>Since 3.7.0</span> + </li> + <li> + The optional <code>cache_clean_interval</code> attribute defines + an interval (in seconds). All cache entries that haven't been + accessed during that interval are removed from memory. This option + is only valid when the driver type is qcow2. The defaut value is 0, + which disables this feature. + <span class='since'>Since 3.7.0</span> + </li> </ul> </dd> <dt><code>backenddomain</code></dt> diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng index 06c5a91..5545179 100644 --- a/docs/schemas/domaincommon.rng +++ b/docs/schemas/domaincommon.rng @@ -1797,6 +1797,15 @@ <ref name="driverIOThread"/> </optional> <optional> + <ref name="qcow2_l2_cache_size"/> + </optional> + <optional> + <ref name="qcow2_refcount_cache_size"/> + </optional> + <optional> + <ref name="qcow2_cache_clean_interval"/> + </optional> + <optional> <ref name="detect_zeroes"/> </optional> <ref name="virtioOptions"/> @@ -1895,6 +1904,21 @@ </choice> </attribute> </define> + <define name="qcow2_l2_cache_size"> + <attribute name='l2_cache_size'> + <ref name="unsignedInt"/> + </attribute> + </define> + <define name="qcow2_refcount_cache_size"> + <attribute name='refcount_cache_size'> + <ref name="unsignedInt"/> + </attribute> + </define> + <define name="qcow2_cache_clean_interval"> + <attribute name='cache_clean_interval'> + <ref name="unsignedInt"/> + </attribute> + </define> <define name="controller"> <element name="controller"> <optional> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index f7574d7..f07ab72 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -8600,6 +8600,30 @@ virDomainDiskDefDriverParseXML(virDomainDiskDefPtr def, VIR_FREE(tmp); } + if ((tmp = virXMLPropString(cur, "l2_cache_size")) && + (virStrToLong_ui(tmp, NULL, 10, &def->src->l2_cache_size) < 0)) { + virReportError(VIR_ERR_XML_ERROR, + _("Invalid l2_cache_size attribute in disk driver element: %s"), + tmp); + goto cleanup; + } + + if ((tmp = virXMLPropString(cur, "refcount_cache_size")) && + (virStrToLong_ui(tmp, NULL, 10, &def->src->refcount_cache_size) < 0)) { + virReportError(VIR_ERR_XML_ERROR, + _("Invalid refcount_cache_size attribute in disk driver element: %s"), + tmp); + goto cleanup; + } + + if ((tmp = virXMLPropString(cur, "cache_clean_interval")) && + (virStrToLong_ui(tmp, NULL, 10, &def->src->cache_clean_interval) < 0)) { + virReportError(VIR_ERR_XML_ERROR, + _("Invalid cache_clean_interval attribute in disk driver element: %s"), + tmp); + goto cleanup; + } + if ((tmp = virXMLPropString(cur, "detect_zeroes")) && (def->detect_zeroes = virDomainDiskDetectZeroesTypeFromString(tmp)) <= 0) { virReportError(VIR_ERR_CONFIG_UNSUPPORTED, @@ -21897,6 +21921,12 @@ virDomainDiskDefFormat(virBufferPtr buf, virBufferAsprintf(&driverBuf, " iothread='%u'", def->iothread); if (def->detect_zeroes) virBufferAsprintf(&driverBuf, " detect_zeroes='%s'", detect_zeroes); + if (def->src->l2_cache_size > 0) + virBufferAsprintf(&driverBuf, " l2_cache_size='%u'", def->src->l2_cache_size); + if (def->src->refcount_cache_size > 0) + virBufferAsprintf(&driverBuf, " refcount_cache_size='%u'", def->src->refcount_cache_size); + if (def->src->cache_clean_interval > 0) + virBufferAsprintf(&driverBuf, " cache_clean_interval='%u'", def->src->cache_clean_interval); virDomainVirtioOptionsFormat(&driverBuf, def->virtio); diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c index 9a27987..7996eed 100644 --- a/src/qemu/qemu_command.c +++ b/src/qemu/qemu_command.c @@ -1430,6 +1430,12 @@ qemuBuildDriveSourceStr(virDomainDiskDefPtr disk, qemuformat = "luks"; virBufferAsprintf(buf, "format=%s,", qemuformat); } + if (disk->src->format == VIR_STORAGE_FILE_QCOW2 && disk->src->l2_cache_size > 0) + virBufferAsprintf(buf, "l2-cache-size=%u,", disk->src->l2_cache_size); + if (disk->src->format == VIR_STORAGE_FILE_QCOW2 && disk->src->refcount_cache_size > 0) + virBufferAsprintf(buf, "refcount-cache-size=%u,", disk->src->refcount_cache_size); + if (disk->src->format == VIR_STORAGE_FILE_QCOW2 && disk->src->cache_clean_interval > 0) + virBufferAsprintf(buf, "cache-clean-interval=%u,", disk->src->cache_clean_interval); ret = 0; diff --git a/src/util/virstoragefile.c b/src/util/virstoragefile.c index fbc8245..c685331 100644 --- a/src/util/virstoragefile.c +++ b/src/util/virstoragefile.c @@ -2038,6 +2038,9 @@ virStorageSourceCopy(const virStorageSource *src, ret->physical = src->physical; ret->readonly = src->readonly; ret->shared = src->shared; + ret->l2_cache_size = src->l2_cache_size; + ret->refcount_cache_size = src->refcount_cache_size; + ret->cache_clean_interval = src->cache_clean_interval; /* storage driver metadata are not copied */ ret->drv = NULL; diff --git a/src/util/virstoragefile.h b/src/util/virstoragefile.h index 6c388b1..e7889d9 100644 --- a/src/util/virstoragefile.h +++ b/src/util/virstoragefile.h @@ -280,6 +280,10 @@ struct _virStorageSource { /* metadata that allows identifying given storage source */ char *nodeformat; /* name of the format handler object */ char *nodestorage; /* name of the storage object */ + + unsigned l2_cache_size; /* qcow2 l2 cache size */ + unsigned refcount_cache_size; /* qcow2 reference count table cache size */ + unsigned cache_clean_interval; /* clean unused cache entries interval */ }; diff --git a/tests/qemuxml2argvdata/qemuxml2argv-disk-drive-qcow2-cache-clean-interval.xml b/tests/qemuxml2argvdata/qemuxml2argv-disk-drive-qcow2-cache-clean-interval.xml new file mode 100644 index 0000000..1c3174d --- /dev/null +++ b/tests/qemuxml2argvdata/qemuxml2argv-disk-drive-qcow2-cache-clean-interval.xml @@ -0,0 +1,37 @@ +<domain type='qemu'> + <name>QEMUGuest1</name> + <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid> + <memory unit='KiB'>219136</memory> + <currentMemory unit='KiB'>219136</currentMemory> + <vcpu placement='static'>1</vcpu> + <os> + <type arch='i686' machine='pc'>hvm</type> + <boot dev='hd'/> + </os> + <clock offset='utc'/> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <devices> + <emulator>/usr/bin/qemu-system-i686</emulator> + <disk type='block' device='disk'> + <driver name='qemu' type='qcow2' cache='none' cache_clean_interval='900'/> + <source dev='/dev/HostVG/QEMUGuest1'/> + <target dev='hda' bus='ide'/> + <address type='drive' controller='0' bus='0' target='0' unit='0'/> + </disk> + <disk type='block' device='cdrom'> + <driver name='qemu' type='raw'/> + <source dev='/dev/HostVG/QEMUGuest2'/> + <target dev='hdc' bus='ide'/> + <readonly/> + <address type='drive' controller='0' bus='1' target='0' unit='0'/> + </disk> + <controller type='usb' index='0'/> + <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='none'/> + </devices> +</domain> diff --git a/tests/qemuxml2argvdata/qemuxml2argv-disk-drive-qcow2-l2-cache-size.xml b/tests/qemuxml2argvdata/qemuxml2argv-disk-drive-qcow2-l2-cache-size.xml new file mode 100644 index 0000000..ebe4c3c --- /dev/null +++ b/tests/qemuxml2argvdata/qemuxml2argv-disk-drive-qcow2-l2-cache-size.xml @@ -0,0 +1,37 @@ +<domain type='qemu'> + <name>QEMUGuest1</name> + <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid> + <memory unit='KiB'>219136</memory> + <currentMemory unit='KiB'>219136</currentMemory> + <vcpu placement='static'>1</vcpu> + <os> + <type arch='i686' machine='pc'>hvm</type> + <boot dev='hd'/> + </os> + <clock offset='utc'/> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <devices> + <emulator>/usr/bin/qemu-system-i686</emulator> + <disk type='block' device='disk'> + <driver name='qemu' type='qcow2' cache='none' l2_cache_size='2097152'/> + <source dev='/dev/HostVG/QEMUGuest1'/> + <target dev='hda' bus='ide'/> + <address type='drive' controller='0' bus='0' target='0' unit='0'/> + </disk> + <disk type='block' device='cdrom'> + <driver name='qemu' type='raw'/> + <source dev='/dev/HostVG/QEMUGuest2'/> + <target dev='hdc' bus='ide'/> + <readonly/> + <address type='drive' controller='0' bus='1' target='0' unit='0'/> + </disk> + <controller type='usb' index='0'/> + <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='none'/> + </devices> +</domain> diff --git a/tests/qemuxml2argvdata/qemuxml2argv-disk-drive-qcow2-refcount-cache-size.xml b/tests/qemuxml2argvdata/qemuxml2argv-disk-drive-qcow2-refcount-cache-size.xml new file mode 100644 index 0000000..e8835e2 --- /dev/null +++ b/tests/qemuxml2argvdata/qemuxml2argv-disk-drive-qcow2-refcount-cache-size.xml @@ -0,0 +1,37 @@ +<domain type='qemu'> + <name>QEMUGuest1</name> + <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid> + <memory unit='KiB'>219136</memory> + <currentMemory unit='KiB'>219136</currentMemory> + <vcpu placement='static'>1</vcpu> + <os> + <type arch='i686' machine='pc'>hvm</type> + <boot dev='hd'/> + </os> + <clock offset='utc'/> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <devices> + <emulator>/usr/bin/qemu-system-i686</emulator> + <disk type='block' device='disk'> + <driver name='qemu' type='qcow2' cache='none' refcount_cache_size='524288'/> + <source dev='/dev/HostVG/QEMUGuest1'/> + <target dev='hda' bus='ide'/> + <address type='drive' controller='0' bus='0' target='0' unit='0'/> + </disk> + <disk type='block' device='cdrom'> + <driver name='qemu' type='raw'/> + <source dev='/dev/HostVG/QEMUGuest2'/> + <target dev='hdc' bus='ide'/> + <readonly/> + <address type='drive' controller='0' bus='1' target='0' unit='0'/> + </disk> + <controller type='usb' index='0'/> + <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='none'/> + </devices> +</domain> diff --git a/tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-qcow2-cache-clean-interval.xml b/tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-qcow2-cache-clean-interval.xml new file mode 100644 index 0000000..6c1934f --- /dev/null +++ b/tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-qcow2-cache-clean-interval.xml @@ -0,0 +1,41 @@ +<domain type='qemu'> + <name>QEMUGuest1</name> + <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid> + <memory unit='KiB'>219136</memory> + <currentMemory unit='KiB'>219136</currentMemory> + <vcpu placement='static'>1</vcpu> + <os> + <type arch='i686' machine='pc'>hvm</type> + <boot dev='hd'/> + </os> + <clock offset='utc'/> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <devices> + <emulator>/usr/bin/qemu-system-i686</emulator> + <disk type='block' device='disk'> + <driver name='qemu' type='qcow2' cache='none' cache_clean_interval='900'/> + <source dev='/dev/HostVG/QEMUGuest1'/> + <target dev='hda' bus='ide'/> + <address type='drive' controller='0' bus='0' target='0' unit='0'/> + </disk> + <disk type='block' device='cdrom'> + <driver name='qemu' type='raw'/> + <source dev='/dev/HostVG/QEMUGuest2'/> + <target dev='hdc' bus='ide'/> + <readonly/> + <address type='drive' controller='0' bus='1' target='0' unit='0'/> + </disk> + <controller type='usb' index='0'> + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/> + </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='none'/> + </devices> +</domain> diff --git a/tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-qcow2-l2-cache-size.xml b/tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-qcow2-l2-cache-size.xml new file mode 100644 index 0000000..4da0e4d --- /dev/null +++ b/tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-qcow2-l2-cache-size.xml @@ -0,0 +1,41 @@ +<domain type='qemu'> + <name>QEMUGuest1</name> + <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid> + <memory unit='KiB'>219136</memory> + <currentMemory unit='KiB'>219136</currentMemory> + <vcpu placement='static'>1</vcpu> + <os> + <type arch='i686' machine='pc'>hvm</type> + <boot dev='hd'/> + </os> + <clock offset='utc'/> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <devices> + <emulator>/usr/bin/qemu-system-i686</emulator> + <disk type='block' device='disk'> + <driver name='qemu' type='qcow2' cache='none' l2_cache_size='2097152'/> + <source dev='/dev/HostVG/QEMUGuest1'/> + <target dev='hda' bus='ide'/> + <address type='drive' controller='0' bus='0' target='0' unit='0'/> + </disk> + <disk type='block' device='cdrom'> + <driver name='qemu' type='raw'/> + <source dev='/dev/HostVG/QEMUGuest2'/> + <target dev='hdc' bus='ide'/> + <readonly/> + <address type='drive' controller='0' bus='1' target='0' unit='0'/> + </disk> + <controller type='usb' index='0'> + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/> + </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='none'/> + </devices> +</domain> diff --git a/tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-qcow2-refcount-cache-size.xml b/tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-qcow2-refcount-cache-size.xml new file mode 100644 index 0000000..bda4574 --- /dev/null +++ b/tests/qemuxml2xmloutdata/qemuxml2xmlout-disk-drive-qcow2-refcount-cache-size.xml @@ -0,0 +1,41 @@ +<domain type='qemu'> + <name>QEMUGuest1</name> + <uuid>c7a5fdbd-edaf-9455-926a-d65c16db1809</uuid> + <memory unit='KiB'>219136</memory> + <currentMemory unit='KiB'>219136</currentMemory> + <vcpu placement='static'>1</vcpu> + <os> + <type arch='i686' machine='pc'>hvm</type> + <boot dev='hd'/> + </os> + <clock offset='utc'/> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <devices> + <emulator>/usr/bin/qemu-system-i686</emulator> + <disk type='block' device='disk'> + <driver name='qemu' type='qcow2' cache='none' refcount_cache_size='524288'/> + <source dev='/dev/HostVG/QEMUGuest1'/> + <target dev='hda' bus='ide'/> + <address type='drive' controller='0' bus='0' target='0' unit='0'/> + </disk> + <disk type='block' device='cdrom'> + <driver name='qemu' type='raw'/> + <source dev='/dev/HostVG/QEMUGuest2'/> + <target dev='hdc' bus='ide'/> + <readonly/> + <address type='drive' controller='0' bus='1' target='0' unit='0'/> + </disk> + <controller type='usb' index='0'> + <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/> + </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='none'/> + </devices> +</domain> diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c index 311b713..a1af6e5 100644 --- a/tests/qemuxml2xmltest.c +++ b/tests/qemuxml2xmltest.c @@ -461,6 +461,9 @@ mymain(void) DO_TEST("disk-drive-cache-v2-none", NONE); DO_TEST("disk-drive-cache-directsync", NONE); DO_TEST("disk-drive-cache-unsafe", NONE); + DO_TEST("disk-drive-qcow2-l2-cache-size", NONE); + DO_TEST("disk-drive-qcow2-refcount-cache-size", NONE); + DO_TEST("disk-drive-qcow2-cache-clean-interval", NONE); DO_TEST("disk-drive-network-nbd", NONE); DO_TEST("disk-drive-network-nbd-export", NONE); DO_TEST("disk-drive-network-nbd-ipv6", NONE); -- 1.8.3.1