Hello Experts,

I am using RHEL Kernal 6.5 on a ATCA H/W with Intel NIC card with “driver: ixgbe, version: 3.15.1-k”.
Strangely I was not able to use some of the “Coalescing” setting with this combination using ethtool.

Ex: I was able to modify ‘rx-usecs’ but I could not modify ‘tx-usecs’ it is throwing the bellow error,

root@acshelf4d1> ethtool -C eth0 tx-usecs 1000
Cannot set device coalesce parameters: Invalid argument

I tried with different values (starting from 100) thinking that 1000 is beyond allowed range by ixgbe. But the result is same.

Same way I was not able to set ‘Adaptive RX’ using ethtool. It is not throwing any error when I tried the command but not setting the value as ebllow,

root@acshelf4d1> ethtool -c eth0 (displaying the value)
Coalesce parameters for eth0:
Adaptive RX: off TX: off
stats-block-usecs: 0
sample-interval: 0
pkt-rate-low: 0
pkt-rate-high: 0

root@acshelf4d1> ethtool -C eth0 adaptive-rx on (command accepted not throwing any error)

root@acshelf4d1> ethtool -c eth0 (displaying again but value not changed)
Coalesce parameters for eth0:
Adaptive RX: off TX: off
stats-block-usecs: 0
sample-interval: 0
pkt-rate-low: 0

Can some one confirm is this is not supported with Intel ixgbe driver or if there is alternate way to do this.

Here are the details of the driver i am using.

root@acshelf4d1> ethtool -i eth0
driver: ixgbe
version: 3.15.1-k
firmware-version: 0x8000018d
bus-info: 0000:0f:00.0
supports-statistics: yes
supports-test: yes
supports-eeprom-access: yes
supports-register-dump: yes
supports-priv-flags: no

root@acshelf4d1> lspci
0f:00.0 Ethernet controller: Intel Corporation 82599 10 Gigabit Dual Port Network Connection (rev 01)

BR
Ananth

From code of ixgbe version 3.15.1, the coalesce support is there.