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linux/drivers/net/hyperv
Erni Sri Satya Vennela 646f071d31 net: netvsc: Update default VMBus channels
Change VMBus channels macro (VRSS_CHANNEL_DEFAULT) in
Linux netvsc from 8 to 16 to align with Azure Windows VM
and improve networking throughput.

For VMs having less than 16 vCPUS, the channels depend
on number of vCPUs. For greater than 16 vCPUs,
set the channels to maximum of VRSS_CHANNEL_DEFAULT and
number of physical cores / 2 which is returned by
netif_get_num_default_rss_queues() as a way to optimize CPU
resource utilization and scale for high-end processors with
many cores.
Maximum number of channels are by default set to 64.

Based on this change the channel creation would change as follows:

-----------------------------------------------------------------
| No. of vCPU |  dev_info->num_chn |    channels created        |
-----------------------------------------------------------------
|    1-16     |        16	   |          vCPU              |
|    >16      |  max(16,#cores/2)  | min(64 , max(16,#cores/2)) |
-----------------------------------------------------------------

Performance tests showed significant improvement in throughput:
- 0.54% for 16 vCPUs
- 0.83% for 32 vCPUs
- 0.86% for 48 vCPUs
- 9.72% for 64 vCPUs
- 13.57% for 96 vCPUs

Signed-off-by: Erni Sri Satya Vennela <ernis@linux.microsoft.com>
Reviewed-by: Haiyang Zhang <haiyangz@microsoft.com>
Reviewed-by: Shradha Gupta <shradhagupta@linux.microsoft.com>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Link: https://patch.msgid.link/1724735791-22815-1-git-send-email-ernis@linux.microsoft.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-28 17:18:32 -07:00
..
hyperv_net.h net: netvsc: Update default VMBus channels 2024-08-28 17:18:32 -07:00
Kconfig
Makefile
netvsc_bpf.c net: refactor ->ndo_bpf calls into dev_xdp_propagate 2024-08-24 15:27:22 +01:00
netvsc_drv.c net: netvsc: Update default VMBus channels 2024-08-28 17:18:32 -07:00
netvsc_trace.c
netvsc_trace.h tracing/treewide: Remove second parameter of __assign_str() 2024-05-22 20:14:47 -04:00
netvsc.c hv_netvsc: Don't free decrypted memory 2024-04-10 21:33:32 +00:00
rndis_filter.c