The patch add support L2 table cache for qcow2 disk. L2 table cache can improve IO read and write performance for qcow2 img.
Diff follows:
src/conf/domain_conf.c | 47 +++++++++++++++++++++++++++++++++++++++++++++++
src/conf/domain_conf.h | 5 +++++
src/qemu/qemu_command.c | 7 +++++++
src/qemu/qemu_domain.c | 6 ++++++
tests/qemuxml2argvdata/qemuxml2argv-disk-virtio.args | 2 +-
tests/qemuxml2argvdata/qemuxml2argv-disk-virtio.xml | 3 ++-
6 files changed, 68 insertions(+), 2 deletions(-)
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index beca0be..0a6afca 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -8058,6 +8058,8 @@ virDomainDiskDefParseXML(virDomainXMLOptionPtr xmlopt,
char *domain_name = NULL;
int expected_secret_usage = -1;
int auth_secret_usage = -1;
+ char *disk_l2_cache_size = NULL;
+ char *disk_cache_clean_interval = NULL;
if (!(def = virDomainDiskDefNew(xmlopt)))
return NULL;
@@ -8233,6 +8235,27 @@ virDomainDiskDefParseXML(virDomainXMLOptionPtr xmlopt,
}
} else if (xmlStrEqual(cur->name, BAD_CAST "boot")) {
/* boot is parsed as part of virDomainDeviceInfoParseXML */
+ } else if (xmlStrEqual(cur->name, BAD_CAST "diskCache")) {
+ disk_l2_cache_size =
+ virXMLPropString(cur, "disk_l2_cache_size");
+ if (disk_l2_cache_size &&
+ virStrToLong_ui(disk_l2_cache_size, NULL, 0,
+ &def->disk_cache.disk_l2_cache_size) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("invalid disk L2 cache size '%s'"),
+ disk_l2_cache_size);
+ goto error;
+ }
+ disk_cache_clean_interval =
+ virXMLPropString(cur, "disk_cache_clean_interval");
+ if (disk_cache_clean_interval &&
+ virStrToLong_ui(disk_cache_clean_interval, NULL, 0,
+ &def->disk_cache.disk_cache_clean_interval) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("invalid disk cache clean interval '%s'"),
+ disk_cache_clean_interval);
+ goto error;
+ }
}
}
@@ -8472,6 +8495,8 @@ virDomainDiskDefParseXML(virDomainXMLOptionPtr xmlopt,
VIR_FREE(vendor);
VIR_FREE(product);
VIR_FREE(domain_name);
+ VIR_FREE(disk_l2_cache_size);
+ VIR_FREE(disk_cache_clean_interval);
ctxt->node = save_ctxt;
return def;
@@ -20646,6 +20671,27 @@ virDomainDiskBlockIoDefFormat(virBufferPtr buf,
}
}
+static void
+virDomainDiskCacheDefFormat(virBufferPtr buf,
+ virDomainDiskDefPtr def)
+{
+ if (def->disk_cache.disk_l2_cache_size > 0 ||
+ def->disk_cache.disk_cache_clean_interval > 0) {
+ virBufferAddLit(buf, "<diskCache");
+ if (def->disk_cache.disk_l2_cache_size > 0) {
+ virBufferAsprintf(buf,
+ " disk_l2_cache_size='%u'",
+ def->disk_cache.disk_l2_cache_size);
+ }
+ if (def->disk_cache.disk_cache_clean_interval > 0) {
+ virBufferAsprintf(buf,
+ " disk_cache_clean_interval='%u'",
+ def->disk_cache.disk_cache_clean_interval);
+ }
+ virBufferAddLit(buf, "/>\n");
+ }
+}
+
/* virDomainSourceDefFormatSeclabel:
*
@@ -20990,6 +21036,7 @@ virDomainDiskDefFormat(virBufferPtr buf,
virDomainDiskGeometryDefFormat(buf, def);
virDomainDiskBlockIoDefFormat(buf, def);
+ virDomainDiskCacheDefFormat(buf, def);
/* For now, mirroring is currently output-only: we only output it
* for live domains, therefore we ignore it on input except for
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index 91a33cb..83ea9d3 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -647,6 +647,11 @@ struct _virDomainDiskDef {
unsigned int physical_block_size;
} blockio;
+ struct {
+ unsigned int disk_l2_cache_size;
+ unsigned int disk_cache_clean_interval;
+ } disk_cache;
+
virDomainBlockIoTuneInfo blkdeviotune;
char *serial;
diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
index e087891..7c47cd3 100755
--- a/src/qemu/qemu_command.c
+++ b/src/qemu/qemu_command.c
@@ -1662,6 +1662,13 @@ qemuBuildDriveStr(virDomainDiskDefPtr disk,
if (qemuBuildDriveSourceStr(disk, cfg, &opt, qemuCaps) < 0)
goto error;
+ if (disk->disk_cache.disk_l2_cache_size > 0)
+ virBufferAsprintf(&opt, "l2-cache-size=%u,",
+ disk->disk_cache.disk_l2_cache_size);
+ if (disk->disk_cache.disk_cache_clean_interval > 0)
+ virBufferAsprintf(&opt, "cache-clean-interval=%u,",
+ disk->disk_cache.disk_cache_clean_interval);
+
if (emitDeviceSyntax)
virBufferAddLit(&opt, "if=none");
else
diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c
index 9f165c1..de334a7 100644
--- a/src/qemu/qemu_domain.c
+++ b/src/qemu/qemu_domain.c
@@ -5408,6 +5408,12 @@ qemuDomainDiskChangeSupported(virDomainDiskDefPtr disk,
CHECK_EQ(ioeventfd, "ioeventfd", true);
CHECK_EQ(event_idx, "event_idx", true);
CHECK_EQ(copy_on_read, "copy_on_read", true);
+
+ CHECK_EQ(disk_cache.disk_l2_cache_size,
+ "diskCache disk_l2_cache_size", true);
+ CHECK_EQ(disk_cache.disk_cache_clean_interval,
+ "diskCache disk_cache_clean_interval", true);
+
/* "snapshot" is a libvirt internal field and thus can be changed */
/* startupPolicy is allowed to be updated. Therefore not checked here. */
CHECK_EQ(transient, "transient", true);
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-disk-virtio.args b/tests/qemuxml2argvdata/qemuxml2argv-disk-virtio.args
index b405242..b968302 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-disk-virtio.args
+++ b/tests/qemuxml2argvdata/qemuxml2argv-disk-virtio.args
@@ -22,7 +22,7 @@ QEMU_AUDIO_DRV=none \
-drive file=/dev/HostVG/QEMUGuest2,format=raw,if=none,media=cdrom,\
id=drive-ide0-1-0,readonly=on \
-device ide-drive,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0 \
--drive file=/tmp/data.img,format=raw,if=none,id=drive-virtio-disk0 \
+-drive file=/tmp/data.img,format=qcow2,l2-cache-size=536870912,cache-clean-interval=900,if=none,id=drive-virtio-disk0 \
-device virtio-blk-pci,bus=pci.0,addr=0x3,drive=drive-virtio-disk0,\
id=virtio-disk0 \
-drive file=/tmp/logs.img,format=raw,if=none,id=drive-virtio-disk1 \
diff --git a/tests/qemuxml2argvdata/qemuxml2argv-disk-virtio.xml b/tests/qemuxml2argvdata/qemuxml2argv-disk-virtio.xml
index b843878..43298fb 100644
--- a/tests/qemuxml2argvdata/qemuxml2argv-disk-virtio.xml
+++ b/tests/qemuxml2argvdata/qemuxml2argv-disk-virtio.xml
@@ -28,8 +28,9 @@
<address type='drive' controller='0' bus='1' target='0' unit='0'/>
</disk>
<disk type='file' device='disk'>
- <driver name='qemu' type='raw'/>
+ <driver name='qemu' type='qcow2'/>
<source file='/tmp/data.img'/>
+ <diskCache disk_l2_cache_size='53687' disk_cache_clean_interval='900' />
<target dev='vda' bus='virtio'/>
</disk>
<disk type='file' device='disk'>
Thanks
-- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list
