Re: [libvirt] [PATCH v2.1 19/21] qemu: introduce period/quota tuning for emulator

This patch introduces support of setting emulator's period and quota to limit cpu bandwidth when the vm starts. Also updates XML Schema for new entries and docs. --- docs/formatdomain.html.in | 24 ++++++++++++++++++++++++ docs/schemas/domaincommon.rng | 10 ++++++++++ src/conf/domain_conf.c | 25 +++++++++++++++++++++++-- src/conf/domain_conf.h | 2 ++ src/qemu/qemu_cgroup.c | 11 ++++++++++- 5 files changed, 69 insertions(+), 3 deletions(-) diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in index 81ec2cd..6142f4b 100644 --- a/docs/formatdomain.html.in +++ b/docs/formatdomain.html.in @@ -388,6 +388,8 @@ &lt;shares&gt;2048&lt;/shares&gt; &lt;period&gt;1000000&lt;/period&gt; &lt;quota&gt;-1&lt;/quota&gt; + &lt;emulator_period&gt;1000000&lt;/period&gt; + &lt;emulator_quota&gt;-1&lt;/quota&gt; &lt;/cputune&gt; ... &lt;/domain&gt; @@ -451,6 +453,28 @@ <span class="since">Only QEMU driver support since 0.9.4, LXC since 0.9.10</span> </dd> + + <dt><code>emulator_period</code></dt> + <dd> + The optional <code>emulator_period</code> element specifies the enforcement + interval(unit: microseconds). Within <code>emulator_period</code>, emulator + threads(those excluding vcpus) of the domain will not be allowed to consume + more than <code>emulator_quota</code> worth of runtime. The value should be + in range [1000, 1000000]. A period with value 0 means no value. + <span class="since">Only QEMU driver support since 0.10.0</span> + </dd> + <dt><code>emulator_quota</code></dt> + <dd> + The optional <code>emulator_quota</code> element specifies the maximum + allowed bandwidth(unit: microseconds) for domain's emulator threads(those + excluding vcpus). A domain with <code>emulator_quota</code> as any negative + value indicates that the domain has infinite bandwidth for emulator threads + (those excluding vcpus), which means that it is not bandwidth controlled. + The value should be in range [1000, 18446744073709551] or less than 0. A + quota with value 0 means no value. + <span class="since">Only QEMU driver support since 0.10.0</span> + </dd> + </dl> diff --git a/docs/schemas/domaincommon.rng b/docs/schemas/domaincommon.rng index b02ad96..7aa6e47 100644 --- a/docs/schemas/domaincommon.rng +++ b/docs/schemas/domaincommon.rng @@ -581,6 +581,16 @@ <ref name="cpuquota"/> </element> </optional> + <optional> + <element name="emulator_period"> + <ref name="cpuperiod"/> + </element> + </optional> + <optional> + <element name="emulator_quota"> + <ref name="cpuquota"/> + </element> + </optional> <zeroOrMore> <element name="vcpupin"> <attribute name="vcpu"> diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c index dab9c5d..7bb07b4 100644 --- a/src/conf/domain_conf.c +++ b/src/conf/domain_conf.c @@ -8297,6 +8297,14 @@ static virDomainDefPtr virDomainDefParseXML(virCapsPtr caps, &def->cputune.quota) < 0) def->cputune.quota = 0; + if (virXPathULongLong("string(./cputune/emulator_period[1])", ctxt, + &def->cputune.emulator_period) < 0) + def->cputune.emulator_period = 0; + + if (virXPathLongLong("string(./cputune/emulator_quota[1])", ctxt, + &def->cputune.emulator_quota) < 0) + def->cputune.emulator_quota = 0; + if ((n = virXPathNodeSet("./cputune/vcpupin", ctxt, &nodes)) < 0) { goto error; } @@ -13030,7 +13038,8 @@ virDomainDefFormatInternal(virDomainDefPtr def, if (def->cputune.shares || def->cputune.vcpupin || def->cputune.period || def->cputune.quota || - def->cputune.emulatorpin) + def->cputune.emulatorpin || + def->cputune.emulator_period || def->cputune.emulator_quota) virBufferAddLit(buf, " <cputune>\n"); if (def->cputune.shares) @@ -13042,6 +13051,17 @@ virDomainDefFormatInternal(virDomainDefPtr def, if (def->cputune.quota) virBufferAsprintf(buf, " <quota>%lld</quota>\n", def->cputune.quota); + + if (def->cputune.emulator_period) + virBufferAsprintf(buf, " <emulator_period>%llu" + "</emulator_period>\n", + def->cputune.emulator_period); + + if (def->cputune.emulator_quota) + virBufferAsprintf(buf, " <emulator_quota>%lld" + "</emulator_quota>\n", + def->cputune.emulator_quota); + if (def->cputune.vcpupin) { for (i = 0; i < def->cputune.nvcpupin; i++) { virBufferAsprintf(buf, " <vcpupin vcpu='%u' ", @@ -13080,7 +13100,8 @@ virDomainDefFormatInternal(virDomainDefPtr def, if (def->cputune.shares || def->cputune.vcpupin || def->cputune.period || def->cputune.quota || - def->cputune.emulatorpin) + def->cputune.emulatorpin || + def->cputune.emulator_period || def->cputune.emulator_quota) virBufferAddLit(buf, " </cputune>\n"); if (def->numatune.memory.nodemask || diff --git a/src/conf/domain_conf.h b/src/conf/domain_conf.h index b6bf5a8..089d9bc 100644 --- a/src/conf/domain_conf.h +++ b/src/conf/domain_conf.h @@ -1598,6 +1598,8 @@ struct _virDomainDef { unsigned long shares; unsigned long long period; long long quota; + unsigned long long emulator_period; + long long emulator_quota; int nvcpupin; virDomainVcpuPinDefPtr *vcpupin; virDomainVcpuPinDefPtr emulatorpin; diff --git a/src/qemu/qemu_cgroup.c b/src/qemu/qemu_cgroup.c index 2fb29b5..2237d11 100644 --- a/src/qemu/qemu_cgroup.c +++ b/src/qemu/qemu_cgroup.c @@ -564,7 +564,7 @@ int qemuSetupCgroupForVcpu(struct qemud_driver *driver, virDomainObjPtr vm) } if (priv->nvcpupids == 0 || priv->vcpupids[0] == vm->pid) { - /* If we does not know VCPU<->PID mapping or all vcpus run in the same + /* If we don't know VCPU<->PID mapping or all vcpu runs in the same * thread, we cannot control each vcpu. */ virReportError(VIR_ERR_INTERNAL_ERROR, "%s", @@ -631,6 +631,8 @@ int qemuSetupCgroupForEmulator(struct qemud_driver *driver, virCgroupPtr cgroup = NULL; virCgroupPtr cgroup_emulator = NULL; virDomainDefPtr def = vm->def; + unsigned long long period = vm->def->cputune.emulator_period; + long long quota = vm->def->cputune.emulator_quota; int rc, i; if (driver->cgroup == NULL) @@ -672,6 +674,13 @@ int qemuSetupCgroupForEmulator(struct qemud_driver *driver, qemuSetupCgroupEmulatorPin(cgroup_emulator, def->cputune.emulatorpin) < 0) goto cleanup; + if (period || quota) { + if (qemuCgroupControllerActive(driver, VIR_CGROUP_CONTROLLER_CPU)) { + if (qemuSetupCgroupVcpuBW(cgroup_emulator, period, quota) < 0) + goto cleanup; + } + } + virCgroupFree(&cgroup_emulator); virCgroupFree(&cgroup); return 0;