Because for Monster SAP HANA VM (1-3 TB RAM) I tuned several AdvSystemSettings.
In the end I was able to speedup vMotion 4x times and utilize 2x flow with 40 Gbps – VIC 1340 with PE.
Inspiration was:
- Multiple-NIC vMotion in vSphere (2007467)
- VMworld 2017 – SER1494BU Encrypted vMotion
- vMotion multi-threading and other tuning settings
- How to Tune vMotion for Lower Migration Times?
It is in production from 04/2018, My tuned final settings is:
| AdvSystemSettings | Default | Tunning | Desc |
|---|---|---|---|
| Migrate.VMotionStreamHelpers | 0 | 8 | Number of helpers to allocate for VMotion streams |
| Net.NetNetqTxPackKpps | 300 | 600 | Max TX queue load (in thousand packet per second) to allow packing on the corresponding RX queue |
| Net.NetNetqTxUnpackKpps | 600 | 1200 | Threshold (in thousand packet per second) for TX queue load to trigger unpacking of the corresponding RX queue |
| Net.MaxNetifTxQueueLen | 2000 | 10000 | Maximum length of the Tx queue for the physical NICs – this alone speeds up VM traffic |
VCF 9 note: Multi-NIC vMotion needs more than one vmk_vmotion per host, and SDDC Manager in VCF 9 accepts only one (KB 407383). On VCF 9 a HANA vMotion is capped by one uplink, so the vNIC layout decides how much it disturbs the NFS log flow. Compare the layouts in SAP HANA on VCF 9: TDI network design and vNIC simulator and why 6 NICs matter for vMotion and NFS.