[libvirt] [PATCH] libxl: don't hardcode scheduler weight

Long ago in commit dfa1e1dd53 the scheduler weight was accidentally hardcoded to 1000. Weight is a setting with no unit since it is relative to the weight of other domains. If no weight is specified, libxl defaults to 256. Instead of hardcoding the weight to 1000, honor any <shares> specified in <cputune>. libvirt's notion of shares is synonomous to libxl's scheduler weight setting. If shares is unspecified, defer default weight setting to libxl. Removing the hardcoded weight required some test fixup. While at it, add an explicit test for <shares> conversion to scheduler weight. Signed-off-by: Jim Fehlig <jfehlig(a)suse.com&gt; --- Honoring <shares> specified by the user is certainly desirable, but I'm not sure about changing the default weight. One problematic scenario that came to mind: Several domains started by pre-patch libvirtd with weight=1000, update libvirtd with patch, start more domains with weight=256. The pre-patch domains unknowingly have a weight nearly 4 times that of post-patch domains. src/libxl/libxl_conf.c | 4 +- tests/libxlxml2domconfigdata/basic-hvm.json | 2 +- tests/libxlxml2domconfigdata/basic-pv.json | 2 +- tests/libxlxml2domconfigdata/cpu-shares-hvm.json | 89 ++++++++++++++++++++++ tests/libxlxml2domconfigdata/cpu-shares-hvm.xml | 39 ++++++++++ tests/libxlxml2domconfigdata/moredevs-hvm.json | 2 +- tests/libxlxml2domconfigdata/multiple-ip.json | 2 +- .../libxlxml2domconfigdata/variable-clock-hvm.json | 2 +- tests/libxlxml2domconfigdata/vnuma-hvm.json | 2 +- tests/libxlxml2domconfigtest.c | 1 + 10 files changed, 138 insertions(+), 7 deletions(-) diff --git a/src/libxl/libxl_conf.c b/src/libxl/libxl_conf.c index dcd46873c..e40145cfa 100644 --- a/src/libxl/libxl_conf.c +++ b/src/libxl/libxl_conf.c @@ -366,7 +366,9 @@ libxlMakeDomBuildInfo(virDomainDefPtr def, } } - b_info->sched_params.weight = 1000; + if (def->cputune.sharesSpecified) + b_info->sched_params.weight = def->cputune.shares; + b_info->max_memkb = virDomainDefGetMemoryInitial(def); b_info->target_memkb = def->mem.cur_balloon; if (hvm) { diff --git a/tests/libxlxml2domconfigdata/basic-hvm.json b/tests/libxlxml2domconfigdata/basic-hvm.json index 6fa41f34f..ccd585385 100644 --- a/tests/libxlxml2domconfigdata/basic-hvm.json +++ b/tests/libxlxml2domconfigdata/basic-hvm.json @@ -19,7 +19,7 @@ "device_model_version": "qemu_xen", "device_model": "/bin/true", "sched_params": { - "weight": 1000 + }, "type.hvm": { "pae": "True", diff --git a/tests/libxlxml2domconfigdata/basic-pv.json b/tests/libxlxml2domconfigdata/basic-pv.json index 7e1abd3d6..0f846daab 100644 --- a/tests/libxlxml2domconfigdata/basic-pv.json +++ b/tests/libxlxml2domconfigdata/basic-pv.json @@ -15,7 +15,7 @@ "max_memkb": 524288, "target_memkb": 524288, "sched_params": { - "weight": 1000 + }, "type.pv": { "bootloader": "pygrub" diff --git a/tests/libxlxml2domconfigdata/cpu-shares-hvm.json b/tests/libxlxml2domconfigdata/cpu-shares-hvm.json new file mode 100644 index 000000000..2e647eada --- /dev/null +++ b/tests/libxlxml2domconfigdata/cpu-shares-hvm.json @@ -0,0 +1,89 @@ +{ + "c_info": { + "type": "hvm", + "name": "test-hvm", + "uuid": "2147d599-9cc6-c0dc-92ab-4064b5446e9b" + }, + "b_info": { + "max_vcpus": 4, + "avail_vcpus": [ + 0, + 1, + 2, + 3 + ], + "max_memkb": 1048576, + "target_memkb": 1048576, + "video_memkb": 8192, + "shadow_memkb": 12288, + "device_model_version": "qemu_xen", + "device_model": "/bin/true", + "sched_params": { + "weight": 1500 + }, + "type.hvm": { + "pae": "True", + "apic": "True", + "acpi": "True", + "vga": { + "kind": "cirrus" + }, + "vnc": { + "enable": "True", + "listen": "0.0.0.0", + "findunused": "False" + }, + "sdl": { + "enable": "False" + }, + "spice": { + + }, + "boot": "c", + "rdm": { + + } + }, + "arch_arm": { + + } + }, + "disks": [ + { + "pdev_path": "/var/lib/xen/images/test-hvm.img", + "vdev": "hda", + "backend": "qdisk", + "format": "raw", + "removable": 1, + "readwrite": 1 + } + ], + "nics": [ + { + "devid": 0, + "mac": "00:16:3e:66:12:b4", + "bridge": "br0", + "script": "/etc/xen/scripts/vif-bridge", + "nictype": "vif_ioemu" + } + ], + "vfbs": [ + { + "devid": -1, + "vnc": { + "enable": "True", + "listen": "0.0.0.0", + "findunused": "False" + }, + "sdl": { + "enable": "False" + } + } + ], + "vkbs": [ + { + "devid": -1 + } + ], + "on_reboot": "restart" +} diff --git a/tests/libxlxml2domconfigdata/cpu-shares-hvm.xml b/tests/libxlxml2domconfigdata/cpu-shares-hvm.xml new file mode 100644 index 000000000..49085b4b7 --- /dev/null +++ b/tests/libxlxml2domconfigdata/cpu-shares-hvm.xml @@ -0,0 +1,39 @@ +<domain type='xen'> + <name>test-hvm</name> + <description>None</description> + <uuid>2147d599-9cc6-c0dc-92ab-4064b5446e9b</uuid> + <memory>1048576</memory> + <currentMemory>1048576</currentMemory> + <vcpu>4</vcpu> + <cputune> + <shares>1500</shares> + </cputune> + <on_poweroff>destroy</on_poweroff> + <on_reboot>restart</on_reboot> + <on_crash>destroy</on_crash> + <clock offset='utc'/> + <os> + <type>hvm</type> + <loader>/usr/lib/xen/boot/hvmloader</loader> + <boot dev='hd'/> + </os> + <features> + <apic/> + <acpi/> + <pae/> + </features> + <devices> + <emulator>/bin/true</emulator> + <disk type='file' device='disk'> + <driver name='qemu'/> + <source file='/var/lib/xen/images/test-hvm.img'/> + <target dev='hda'/> + </disk> + <interface type='bridge'> + <source bridge='br0'/> + <mac address='00:16:3e:66:12:b4'/> + <script path='/etc/xen/scripts/vif-bridge'/> + </interface> + <graphics type='vnc' port='-1' autoport='yes' listen='0.0.0.0'/> + </devices> +</domain> diff --git a/tests/libxlxml2domconfigdata/moredevs-hvm.json b/tests/libxlxml2domconfigdata/moredevs-hvm.json index 8f861f34e..7bfd68bd6 100644 --- a/tests/libxlxml2domconfigdata/moredevs-hvm.json +++ b/tests/libxlxml2domconfigdata/moredevs-hvm.json @@ -21,7 +21,7 @@ "device_model_version": "qemu_xen", "device_model": "/bin/true", "sched_params": { - "weight": 1000 + }, "type.hvm": { "pae": "True", diff --git a/tests/libxlxml2domconfigdata/multiple-ip.json b/tests/libxlxml2domconfigdata/multiple-ip.json index 4aff61d4b..80dca8261 100644 --- a/tests/libxlxml2domconfigdata/multiple-ip.json +++ b/tests/libxlxml2domconfigdata/multiple-ip.json @@ -15,7 +15,7 @@ "max_memkb": 524288, "target_memkb": 524288, "sched_params": { - "weight": 1000 + }, "type.pv": { "bootloader": "pygrub" diff --git a/tests/libxlxml2domconfigdata/variable-clock-hvm.json b/tests/libxlxml2domconfigdata/variable-clock-hvm.json index 49d0a4330..69be9c64c 100644 --- a/tests/libxlxml2domconfigdata/variable-clock-hvm.json +++ b/tests/libxlxml2domconfigdata/variable-clock-hvm.json @@ -21,7 +21,7 @@ "device_model_version": "qemu_xen", "device_model": "/bin/true", "sched_params": { - "weight": 1000 + }, "type.hvm": { "pae": "True", diff --git a/tests/libxlxml2domconfigdata/vnuma-hvm.json b/tests/libxlxml2domconfigdata/vnuma-hvm.json index 3a5071e14..3b2fc5f40 100644 --- a/tests/libxlxml2domconfigdata/vnuma-hvm.json +++ b/tests/libxlxml2domconfigdata/vnuma-hvm.json @@ -107,7 +107,7 @@ "device_model_version": "qemu_xen", "device_model": "/bin/true", "sched_params": { - "weight": 1000 + }, "type.hvm": { "pae": "True", diff --git a/tests/libxlxml2domconfigtest.c b/tests/libxlxml2domconfigtest.c index ea3d2884e..6eec4c752 100644 --- a/tests/libxlxml2domconfigtest.c +++ b/tests/libxlxml2domconfigtest.c @@ -192,6 +192,7 @@ mymain(void) DO_TEST("basic-pv"); DO_TEST("basic-hvm"); + DO_TEST("cpu-shares-hvm"); DO_TEST("variable-clock-hvm"); DO_TEST("moredevs-hvm"); DO_TEST("vnuma-hvm"); -- 2.16.1