Current DPDK limit for num-rx-desc is 8192 which is below the maximum supported by NICs
vyos@VyOS-for-Smoke-Tests# set vpp settings interface eth1 dpdk-options num-rx-desc Possible completions: <256-8192> Number of descriptors in receive ring
For example for AWS ENA on c5.4xlarge machine it is max 16384:
AWS ENA VF carrier up full duplex max-frame-size 1522 flags: admin-up promisc maybe-multiseg tx-offload rx-ip4-cksum int-supported tx-prepare Devargs: rx: queues 5 (max 8), desc 1024 (min 128 max 16384 align 1) tx: queues 6 (max 8), desc 1024 (min 128 max 1024 align 1)
lspci -vvv -s 00:05.0
00:05.0 Ethernet controller: Amazon.com, Inc. Elastic Network Adapter (ENA)
Physical Slot: 5
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx+
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0
Region 0: Memory at febf4000 (32-bit, non-prefetchable) [size=16K]
Region 2: Memory at fe800000 (32-bit, prefetchable) [size=1M]
Region 4: Memory at febd0000 (32-bit, non-prefetchable) [size=64K]
Capabilities: <access denied>
Kernel driver in use: ena
Kernel modules: ena
vyos@VyOS-for-Smoke-Tests# ethtool -i eth1
driver: ena
version: 6.6.106-vyos
firmware-version:
expansion-rom-version:
bus-info: 0000:00:06.0
supports-statistics: yes
supports-test: no
supports-eeprom-access: no
supports-register-dump: no
supports-priv-flags: no
[edit]
vyos@VyOS-for-Smoke-Tests# ethtool -g eth1
Ring parameters for eth1:
Pre-set maximums:
RX: 16384
RX Mini: n/a
RX Jumbo: n/a
TX: 1024
TX push buff len: 224
Current hardware settings:
RX: 1024
RX Mini: n/a
RX Jumbo: n/a
TX: 1024
RX Buf Len: n/a
CQE Size: n/a
TX Push: on
RX Push: off
TX push buff len: 96
TCP data split: n/a
[edit]
vyos@VyOS-for-Smoke-Tests# ethtool -l eth1
Channel parameters for eth1:
Pre-set maximums:
RX: n/a
TX: n/a
Other: n/a
Combined: 8
Current hardware settings:
RX: n/a
TX: n/a
Other: n/a
Combined: 8