12:54 p.m.
From: Masayoshi Mizuma <m.mizuma(a)jp.fujitsu.com>
virtiofsd has --thread-pool-size=NUM option to limit the
thread pool size. It will be useful to tune the performance.
Add pool element to use the option like as:
<filesystem type='mount' accessmode='passthrough'>
<driver type='virtiofs' queue='1024'/>
<binary path='/usr/libexec/virtiofsd' xattr='on'
pool='32'/>
<source dir='/path'/>
<target dir='mount_tag'/>
</filesystem>
Signed-off-by: Masayoshi Mizuma <m.mizuma(a)jp.fujitsu.com>
---
docs/formatdomain.rst | 6 ++++--
docs/schemas/domaincommon.rng | 5 +++++
src/conf/domain_conf.c | 12 ++++++++++++
src/conf/domain_conf.h | 1 +
src/qemu/qemu_virtiofs.c | 3 +++
5 files changed, 25 insertions(+), 2 deletions(-)
diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
index bfa80e4bc2..0f66af5dc3 100644
--- a/docs/formatdomain.rst
+++ b/docs/formatdomain.rst
@@ -3070,7 +3070,7 @@ A directory on the host that can be accessed directly from the
guest.
</filesystem>
<filesystem type='mount' accessmode='passthrough'>
<driver type='virtiofs' queue='1024'/>
- <binary path='/usr/libexec/virtiofsd' xattr='on'>
+ <binary path='/usr/libexec/virtiofsd' xattr='on'
pool='32'>
<cache mode='always'/>
<lock posix='on' flock='on'/>
</binary>
@@ -3188,7 +3188,9 @@ A directory on the host that can be accessed directly from the
guest.
the use of filesystem extended attributes. Caching can be tuned via the
``cache`` element, possible ``mode`` values being ``none`` and ``always``.
Locking can be controlled via the ``lock`` element - attributes ``posix`` and
- ``flock`` both accepting values ``on`` or ``off``. ( :since:`Since 6.2.0` )
+ ``flock`` both accepting values ``on`` or ``off``. ( :since:`Since 6.2.0` ).
+ Thread pool size limit can be tuned via the ``pool`` element.
+ ( :since:`Since 6.9.0` )
``source``
The resource on the host that is being accessed in the guest. The ``name``
attribute must be used with ``type='template'``, and the ``dir`` attribute
diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng
index c25a742581..cd5de2ba80 100644
--- a/docs/schemas/domaincommon.rng
+++ b/docs/schemas/domaincommon.rng
@@ -2839,6 +2839,11 @@
<ref name="virOnOff"/>
</attribute>
</optional>
+ <optional>
+ <attribute name="pool">
+ <ref name="unsignedInt"/>
+ </attribute>
+ </optional>
<optional>
<element name="cache">
<optional>
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index efa5ac527b..9d06f8c75f 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -11588,6 +11588,7 @@ virDomainFSDefParseXML(virDomainXMLOptionPtr xmlopt,
g_autofree char *cache = virXPathString("string(./binary/cache/@mode)",
ctxt);
g_autofree char *posix_lock =
virXPathString("string(./binary/lock/@posix)", ctxt);
g_autofree char *flock = virXPathString("string(./binary/lock/@flock)",
ctxt);
+ g_autofree char *thread_pool_size =
virXPathString("string(./binary/@pool)", ctxt);
int val;
if (queue_size && virStrToLong_ull(queue_size, NULL, 10,
&def->queue_size) < 0) {
@@ -11597,6 +11598,14 @@ virDomainFSDefParseXML(virDomainXMLOptionPtr xmlopt,
goto error;
}
+ if (thread_pool_size &&
+ virStrToLong_ull(thread_pool_size, NULL, 10, &def->thread_pool_size)
< 0) {
+ virReportError(VIR_ERR_XML_ERROR,
+ _("cannot parse thread pool size '%s' for
virtiofs"),
+ thread_pool_size);
+ goto error;
+ }
+
if (binary)
def->binary = virFileSanitizePath(binary);
@@ -26191,6 +26200,9 @@ virDomainFSDefFormat(virBufferPtr buf,
virTristateSwitchTypeToString(def->xattr));
}
+ if (def->thread_pool_size)
+ virBufferAsprintf(&binaryAttrBuf, " pool='%llu'",
def->thread_pool_size);
+
if (def->cache != VIR_DOMAIN_FS_CACHE_MODE_DEFAULT) {
virBufferAsprintf(&binaryBuf, "<cache
mode='%s'/>\n",
virDomainFSCacheModeTypeToString(def->cache));
diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h
index cd344716a3..98ab0a51c7 100644
--- a/src/conf/domain_conf.h
+++ b/src/conf/domain_conf.h
@@ -860,6 +860,7 @@ struct _virDomainFSDef {
bool symlinksResolved;
char *binary;
unsigned long long queue_size;
+ unsigned long long thread_pool_size;
virTristateSwitch xattr;
virDomainFSCacheMode cache;
virTristateSwitch posix_lock;
diff --git a/src/qemu/qemu_virtiofs.c b/src/qemu/qemu_virtiofs.c
index 2e239cad66..e35c278a1b 100644
--- a/src/qemu/qemu_virtiofs.c
+++ b/src/qemu/qemu_virtiofs.c
@@ -126,6 +126,9 @@ qemuVirtioFSBuildCommandLine(virQEMUDriverConfigPtr cfg,
virCommandPassFD(cmd, *fd, VIR_COMMAND_PASS_FD_CLOSE_PARENT);
*fd = -1;
+ if (fs->thread_pool_size)
+ virCommandAddArgFormat(cmd, "--thread-pool-size=%llu",
fs->thread_pool_size);
+
virCommandAddArg(cmd, "-o");
virBufferAddLit(&opts, "source=");
virQEMUBuildBufferEscapeComma(&opts, fs->src->path);
--
2.27.0