At least in case of QEMU an IOThread is actually a pool of
threads (see iothread_set_aio_context_params() in QEMU's code
base). As such, it can have minimal and maximal number of worker
threads. Allow setting them in domain XML.
Signed-off-by: Michal Privoznik <mprivozn@xxxxxxxxxx>
---
docs/formatdomain.rst | 5 +-
src/conf/domain_conf.c | 34 ++++++++++-
src/conf/domain_conf.h | 3 +
src/conf/schemas/domaincommon.rng | 10 +++
.../iothreads-ids-pool-sizes.xml | 61 +++++++++++++++++++
...iothreads-ids-pool-sizes.x86_64-latest.xml | 1 +
tests/qemuxml2xmltest.c | 1 +
7 files changed, 111 insertions(+), 4 deletions(-)
create mode 100644 tests/qemuxml2argvdata/iothreads-ids-pool-sizes.xml
create mode 120000 tests/qemuxml2xmloutdata/iothreads-ids-pool-sizes.x86_64-latest.xml
diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
index 312b605a8b..2aa39b2f63 100644
--- a/docs/formatdomain.rst
+++ b/docs/formatdomain.rst
@@ -675,7 +675,7 @@ host/guest with many LUNs. :since:`Since 1.2.8 (QEMU only)`
<iothread id="2"/>
<iothread id="4"/>
<iothread id="6"/>
- <iothread id="8"/>
+ <iothread id="8" thread_pool_min="2" thread_pool_max="32"/>
</iothreadids>
...
</domain>
@@ -696,6 +696,9 @@ host/guest with many LUNs. :since:`Since 1.2.8 (QEMU only)`
any predefined ``id``. If there are more ``iothreadids`` defined than
``iothreads`` defined for the domain, then the ``iothreads`` value will be
adjusted accordingly. :since:`Since 1.2.15`
+ The element has two optional attributes ``thread_pool_min`` and
+ ``hread_pool_max`` which allow setting lower and upper boundary for number
+ of worker threads for given IOThread. :since:`Since 8.5.0`
CPU Tuning
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 8d4b27dbc0..8891289866 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -3481,6 +3481,9 @@ virDomainIOThreadIDDefNew(void)
{
virDomainIOThreadIDDef *def = g_new0(virDomainIOThreadIDDef, 1);
+ def->thread_pool_min = -1;
+ def->thread_pool_max = -1;
+
return def;
}
@@ -17008,7 +17011,7 @@ virDomainIdmapDefParseXML(xmlXPathContextPtr ctxt,
*
* <iothreads>4</iothreads>
* <iothreadids>
- * <iothread id='1'/>
+ * <iothread id='1' thread_pool_min="0" thread_pool_max="60"/>
* <iothread id='3'/>
* <iothread id='5'/>
* <iothread id='7'/>
@@ -17024,6 +17027,16 @@ virDomainIOThreadIDDefParseXML(xmlNodePtr node)
&iothrid->iothread_id) < 0)
return NULL;
+ if (virXMLPropInt(node, "thread_pool_min", 10,
+ VIR_XML_PROP_NONNEGATIVE,
+ &iothrid->thread_pool_min, -1) < 0)
+ return NULL;
+
+ if (virXMLPropInt(node, "thread_pool_max", 10,
+ VIR_XML_PROP_NONNEGATIVE,
+ &iothrid->thread_pool_max, -1) < 0)
+ return NULL;
+
return g_steal_pointer(&iothrid);
}
@@ -27607,8 +27620,23 @@ virDomainDefIOThreadsFormat(virBuffer *buf,
return;
for (i = 0; i < def->niothreadids; i++) {
- virBufferAsprintf(&childrenBuf, "<iothread id='%u'/>\n",
- def->iothreadids[i]->iothread_id);
+ virDomainIOThreadIDDef *iothread = def->iothreadids[i];
+ virBuffer attrBuf = VIR_BUFFER_INITIALIZER;
+
+ virBufferAsprintf(&attrBuf, " id='%u'",
+ iothread->iothread_id);
+
+ if (iothread->thread_pool_min >= 0) {
+ virBufferAsprintf(&attrBuf, " thread_pool_min='%d'",
+ iothread->thread_pool_min);
+ }
+
+ if (iothread->thread_pool_max >= 0) {
+ virBufferAsprintf(&attrBuf, " thread_pool_max='%d'",
+ iothread->thread_pool_max);
+ }
+
+ virXMLFormatElement(&childrenBuf, "iothread", &attrBuf, NULL);
}
virXMLFormatElement(buf, "iothreadids", NULL, &childrenBuf);
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index e7e0f24443..2a5001f15c 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -2646,6 +2646,9 @@ struct _virDomainIOThreadIDDef {
virBitmap *cpumask;
virDomainThreadSchedParam sched;
+
+ int thread_pool_min;
+ int thread_pool_max;
};
void virDomainIOThreadIDDefFree(virDomainIOThreadIDDef *def);
diff --git a/src/conf/schemas/domaincommon.rng b/src/conf/schemas/domaincommon.rng
index cc598212a8..7e6310832b 100644
--- a/src/conf/schemas/domaincommon.rng
+++ b/src/conf/schemas/domaincommon.rng
@@ -829,6 +829,16 @@
<attribute name="id">
<ref name="unsignedInt"/>
</attribute>
+ <optional>
+ <attribute name="thread_pool_min">
+ <ref name="unsignedLong"/>
+ </attribute>
+ </optional>
+ <optional>
+ <attribute name="thread_pool_max">
+ <ref name="unsignedLong"/>
+ </attribute>
+ </optional>
</element>
</zeroOrMore>
</element>
diff --git a/tests/qemuxml2argvdata/iothreads-ids-pool-sizes.xml b/tests/qemuxml2argvdata/iothreads-ids-pool-sizes.xml
new file mode 100644
index 0000000000..0f93d14f12
--- /dev/null
+++ b/tests/qemuxml2argvdata/iothreads-ids-pool-sizes.xml
@@ -0,0 +1,61 @@
+<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'>6</vcpu>
+ <iothreads>5</iothreads>
+ <iothreadids>
+ <iothread id='2' thread_pool_min='0' thread_pool_max='60'/>
+ <iothread id='4' thread_pool_min='1' thread_pool_max='1'/>
+ <iothread id='1'/>
+ <iothread id='3'/>
+ <iothread id='5'/>
+ </iothreadids>
+ <os>
+ <type arch='x86_64' machine='q35'>hvm</type>
+ <boot dev='hd'/>
+ </os>
+ <cpu mode='custom' match='exact' check='none'>
+ <model fallback='forbid'>qemu64</model>
+ </cpu>
+ <clock offset='utc'/>
+ <on_poweroff>destroy</on_poweroff>
+ <on_reboot>restart</on_reboot>
+ <on_crash>destroy</on_crash>
+ <devices>
+ <emulator>/usr/bin/qemu-system-x86_64</emulator>
+ <disk type='block' device='disk'>
+ <driver name='qemu' type='raw'/>
+ <source dev='/dev/HostVG/QEMUGuest1'/>
+ <target dev='vda' bus='virtio'/>
+ <address type='pci' domain='0x0000' bus='0x02' slot='0x00' function='0x0'/>
+ </disk>
+ <controller type='pci' index='0' model='pcie-root'/>
+ <controller type='pci' index='1' model='pcie-root-port'>
+ <model name='pcie-root-port'/>
+ <target chassis='1' port='0x8'/>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0' multifunction='on'/>
+ </controller>
+ <controller type='pci' index='2' model='pcie-root-port'>
+ <model name='pcie-root-port'/>
+ <target chassis='2' port='0x9'/>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
+ </controller>
+ <controller type='pci' index='3' model='pcie-root-port'>
+ <model name='pcie-root-port'/>
+ <target chassis='3' port='0xa'/>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
+ </controller>
+ <controller type='usb' index='0' model='qemu-xhci'>
+ <address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
+ </controller>
+ <controller type='sata' index='0'>
+ <address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
+ </controller>
+ <input type='mouse' bus='ps2'/>
+ <input type='keyboard' bus='ps2'/>
+ <audio id='1' type='none'/>
+ <memballoon model='none'/>
+ </devices>
+</domain>
diff --git a/tests/qemuxml2xmloutdata/iothreads-ids-pool-sizes.x86_64-latest.xml b/tests/qemuxml2xmloutdata/iothreads-ids-pool-sizes.x86_64-latest.xml
new file mode 120000
index 0000000000..6ed642fe5f
--- /dev/null
+++ b/tests/qemuxml2xmloutdata/iothreads-ids-pool-sizes.x86_64-latest.xml
@@ -0,0 +1 @@
+../qemuxml2argvdata/iothreads-ids-pool-sizes.xml
\ No newline at end of file
diff --git a/tests/qemuxml2xmltest.c b/tests/qemuxml2xmltest.c
index 3bd57306cc..b85d5fb757 100644
--- a/tests/qemuxml2xmltest.c
+++ b/tests/qemuxml2xmltest.c
@@ -597,6 +597,7 @@ mymain(void)
DO_TEST_NOCAPS("smp");
DO_TEST_NOCAPS("iothreads");
DO_TEST_NOCAPS("iothreads-ids");
+ DO_TEST_CAPS_LATEST("iothreads-ids-pool-sizes");
DO_TEST_NOCAPS("iothreads-ids-partial");
DO_TEST_NOCAPS("cputune-iothreads");
DO_TEST_NOCAPS("iothreads-disk");
--
2.35.1
