Hi Gianluca,
Thanks for your email,
Please find the required details attached,
I just want to highlight that the issue only occurred on ubuntu VMs. There
are other VMs running on the same host that all work fine.
*other VM ( Rocky 9.3 ) on the same host. *
[root@ay-pgsql ~]# speedtest
Server: Ishan netsol - Chennai (id: 58611)
ISP: Tata Teleservices ISP
Idle Latency: 1.94 ms (jitter: 0.03ms, low: 1.89ms, high: 1.95ms)
Download: 881.00 Mbps (data used: 703.6 MB)
33.83 ms (jitter: 2.58ms, low: 2.75ms, high: 43.35ms)
Upload: 637.42 Mbps (data used: 733.2 MB)
5.93 ms (jitter: 1.72ms, low: 2.23ms, high: 16.75ms)
Packet Loss: 0.0%
Result URL:
https://www.speedtest.net/result/c/28352555-321a-4e25-ab86-033f48a8e377
[root@ay- pgsql ~]# cat /etc/os
os-release ostree/
[root@ay-redis ~]# cat /etc/os-release
NAME="Rocky Linux"
VERSION="9.5 (Blue Onyx)"
ID="rocky"
ID_LIKE="rhel centos fedora"
VERSION_ID="9.5"
PLATFORM_ID="platform:el9"
PRETTY_NAME="Rocky Linux 9.5 (Blue Onyx)"
ANSI_COLOR="0;32"
LOGO="fedora-logo-icon"
CPE_NAME="cpe:/o:rocky:rocky:9::baseos"
HOME_URL="https://rockylinux.org/";
VENDOR_NAME="RESF"
VENDOR_URL="https://resf.org/";
BUG_REPORT_URL="https://bugs.rockylinux.org/";
SUPPORT_END="2032-05-31"
ROCKY_SUPPORT_PRODUCT="Rocky-Linux-9"
ROCKY_SUPPORT_PRODUCT_VERSION="9.5"
REDHAT_SUPPORT_PRODUCT="Rocky Linux"
REDHAT_SUPPORT_PRODUCT_VERSION="9.5"
--------------------------------------------------------------------------------------------------------------------
*ubuntu (24.04) VM on the same host.*
bot-admin@kt-pgsql:~$ speedtest-cli
Retrieving speedtest.net configuration...
Testing from Tata Teleservices ISP (14.99.127.154)...
Retrieving speedtest.net server list...
Selecting best server based on ping...
Hosted by ACT FIBERNET (Chennai) [424.08 km]: 2.509 ms
Testing download
speed................................................................................
*Download: 9.75 Mbit/s*
Testing upload
speed......................................................................................................
Upload: 547.05 Mbit/s
bot-admin@kt-pgsql:~$ cat /etc/os-release
PRETTY_NAME="Ubuntu 24.04.1 LTS"
NAME="Ubuntu"
VERSION_ID="24.04"
VERSION="24.04.1 LTS (Noble Numbat)"
VERSION_CODENAME=noble
ID=ubuntu
ID_LIKE=debian
HOME_URL="https://www.ubuntu.com/";
SUPPORT_URL="https://help.ubuntu.com/";
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/";
PRIVACY_POLICY_URL="
https://www.ubuntu.com/legal/terms-and-policies/privacy-policy";
UBUNTU_CODENAME=noble
LOGO=ubuntu-logo
Warm Regards,
<http://www.botvfx.com/>
Dhayanand S (He/Him)
IT Operations Lead
Chennai, India
O +91 (44) 4269 1273 x 920
M +91-9840597021
[image: FB]
<http://www.facebook.com/pages/botvfx/101770726526437?ref=search/> [image:
LinkedIn] <http://www.linkedin.com/company/710872/> [image: twitter]
<https://twitter.com/botvfx/> [image: Instagram]
<https://www.instagram.com/botvfx/>
Put the bot to work for you. <http://www.botvfx.com/>
On Tue, Jun 10, 2025 at 2:31 PM Gianluca Cecchi <[email protected]>
wrote:
> On Tue, Jun 10, 2025 at 10:25 AM dhayanands--- via Users <[email protected]>
> wrote:
>
>> Hi team,
>>
>> We’re facing a strange issue with network performance on one of our oVirt
>> hosts and would like to get insights or guidance on possible
>> misconfigurations or compatibility problems.
>>
>> Environment Details:
>> oVirt Version: 4.5.5
>>
>> Cluster CPU Type: Intel IceLake Server Family (default)
>>
>> Host A (Issue observed):
>>
>> CPU: Intel Xeon Platinum 8562Y+ (Sapphire Rapids)
>>
>> CPU Family/Model: Family 6 / Model 207 / Stepping 2
>>
>> Host B (Working fine):
>>
>> CPU: Intel Xeon Gold 6354 (Ice Lake)
>>
>> CPU Family/Model: Family 6 / Model 106 / Stepping 6
>>
>> Problem Description:
>> We have a VM (kitsu) that was initially hosted on botovirtnode-006
>> (Platinum 8562Y+). The VM showed very poor download speeds (~10 Mbps),
>> while upload was fine (~680 Mbps). After migrating the same VM to another
>> host (botovirtnode-001 with Gold 6354 CPU), network performance drastically
>> improved:
>>
>> Test On Affected Node On Healthy Node
>> Download ~10 Mbps ~920 Mbps
>> Upload ~680 Mbps ~760 Mbps
>>
>> This clearly indicates a host-specific issue, most likely related to
>> hardware compatibility or CPU feature masking.
>>
>> Troubleshooting Done:
>> Verified VM configurations (same on both hosts).
>>
>> Tested with speedtest-cli multiple times to confirm.
>>
>> Confirmed that VM virtual NIC, vNIC profile, and vSwitch settings are
>> identical.
>>
>> Both hosts are part of the same cluster using the default Intel IceLake
>> Server CPU type.
>>
>> Suspect the issue is due to CPU feature mismatch or unsupported
>> stepping/model in the cluster’s CPU type.
>>
>>
> Hi,
> as a previous Intel employee, just to point out that 8562Y+ is an Emerald
> Rapids CPU, the 5th Generation of Intel Xeon Scalable platform (Sapphire
> Rapids is the 4th, pin/to/pin compatible with Emerald Rapids).
> That said, I would go analyzing the network cards on your newer server, to
> verify the kernel driver used by the OS and eventually some default applied
> settings that could be suboptimal for your config.
> Also, if you are using bonding, if the configuration is the same,
> supposing the upstream switching type is the same
> Link speed, duplex got and so on.
> I don't think the root cause is the cpu, as you have 32 vs 18 cores, base
> freq 2.8 vs 3 GHz, but boost freq 4.1 vs 3.6 GHz, DDR5 vs DDR4, PCIe 5 vs 4
> Which performance profile are you using in BIOS for the 8562Y+, are you
> using speed-step technology and lowering the number of active cores? See
> here:
> https://www.intel.com/content/www/us/en/products/sku/237558/intel-xeon-platinum-8562y-processor-60m-cache-2-80-ghz/specifications.html
> Feel free to share more info on the network cards settings.
> Eg using "lspci -vk" where you also get the kernel driver in use. And
> "ethtool net_interface" and "ethtool -k net_interface" to see aquired
> settings
>
> HIH,
> Gianluca
>
>
--
NOTICE: This e-mail may contain information that is privileged or otherwise
confidential. It is intended solely for the holder of the e-mail address to
which it has been directed, and should not be disseminated, distributed,
copied or forwarded to any other persons. It is not intended for
transmission to, or receipt by, any other person. If you have received this
e-mail in error, please delete it without copying or forwarding it, and
notify us of the error by reply e-mail so that our address records can be
corrected.
[root@botovirtnode-006 ~]# ethtool eno12409np1
Settings for eno12409np1:
Supported ports: [ FIBRE ]
Supported link modes: 10000baseT/Full
25000baseCR/Full
Supported pause frame use: Symmetric Receive-only
Supports auto-negotiation: Yes
Supported FEC modes: RS BASER
Advertised link modes: 10000baseT/Full
25000baseCR/Full
Advertised pause frame use: Symmetric
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Speed: 10000Mb/s
Duplex: Full
Auto-negotiation: on
Port: FIBRE
PHYAD: 0
Transceiver: internal
Supports Wake-on: g
Wake-on: d
Current message level: 0x00002081 (8321)
drv tx_err hw
Link detected: yes[root@botovirtnode-006 ~]# ethtool -k eno12409np1
Features for eno12409np1:
rx-checksumming: on
tx-checksumming: on
tx-checksum-ipv4: on
tx-checksum-ip-generic: off [fixed]
tx-checksum-ipv6: on
tx-checksum-fcoe-crc: off [fixed]
tx-checksum-sctp: off [fixed]
scatter-gather: on
tx-scatter-gather: on
tx-scatter-gather-fraglist: off [fixed]
tcp-segmentation-offload: on
tx-tcp-segmentation: on
tx-tcp-ecn-segmentation: off [fixed]
tx-tcp-mangleid-segmentation: off
tx-tcp6-segmentation: on
generic-segmentation-offload: on
generic-receive-offload: on
large-receive-offload: off
rx-vlan-offload: on
tx-vlan-offload: on
ntuple-filters: on
receive-hashing: on
highdma: on [fixed]
rx-vlan-filter: off [fixed]
vlan-challenged: off [fixed]
tx-lockless: off [fixed]
netns-local: off [fixed]
tx-gso-robust: off [fixed]
tx-fcoe-segmentation: off [fixed]
tx-gre-segmentation: on
tx-gre-csum-segmentation: on
tx-ipxip4-segmentation: on
tx-ipxip6-segmentation: off [fixed]
tx-udp_tnl-segmentation: on
tx-udp_tnl-csum-segmentation: on
tx-gso-partial: on
tx-tunnel-remcsum-segmentation: off [fixed]
tx-sctp-segmentation: off [fixed]
tx-esp-segmentation: off [fixed]
tx-udp-segmentation: off [fixed]
tx-gso-list: off [fixed]
fcoe-mtu: off [fixed]
tx-nocache-copy: off
loopback: off [fixed]
rx-fcs: off [fixed]
rx-all: off [fixed]
tx-vlan-stag-hw-insert: on
rx-vlan-stag-hw-parse: on
rx-vlan-stag-filter: off [fixed]
l2-fwd-offload: off [fixed]
hw-tc-offload: on
esp-hw-offload: off [fixed]
esp-tx-csum-hw-offload: off [fixed]
rx-udp_tunnel-port-offload: on
tls-hw-tx-offload: off [fixed]
tls-hw-rx-offload: off [fixed]
rx-gro-hw: on
tls-hw-record: off [fixed]
rx-gro-list: off
macsec-hw-offload: off [fixed]
rx-udp-gro-forwarding: off
hsr-tag-ins-offload: off [fixed]
hsr-tag-rm-offload: off [fixed]
hsr-fwd-offload: off [fixed]
hsr-dup-offload: off [fixed]
[root@botovirtnode-006 ~]#_______________________________________________
Users mailing list -- [email protected]
To unsubscribe send an email to [email protected]
Privacy Statement: https://www.ovirt.org/privacy-policy.html
oVirt Code of Conduct:
https://www.ovirt.org/community/about/community-guidelines/
List Archives:
https://lists.ovirt.org/archives/list/[email protected]/message/WBF7MOGG57QOISXTUIK5P2YEENLMMAXL/
