From: Jakub Kicinski <kuba@kernel.org>
To: jgh@redhat.com
Cc: netdev@vger.kernel.org
Subject: Re: [RFC PATCH net-next 0/7] NIC driver Rx ring ECN
Date: Wed, 11 Jan 2023 10:46:18 -0800 [thread overview]
Message-ID: <20230111104618.74022e83@kernel.org> (raw)
In-Reply-To: <20230111143427.1127174-1-jgh@redhat.com>
On Wed, 11 Jan 2023 14:34:20 +0000 jgh@redhat.com wrote:
> Stats counters are incremented in ipv4 and ipv6 input processing,
> with results:
>
> $ nstat -sz *Congest*
> #kernel
> Ip6InCongestionPkts 0 0.0
> IpExtInCongestionPkts 148454 0.0
> $
Do you have any reason to believe that it actually helps anything?
NAPI with typical budget of 64 is easily exhausted (you just need
two TSO frames arriving at once with 1500 MTU).
Host level congestion is better detected using time / latency signals.
Timestamp the packet at the NIC and compare the Rx time to current time
when processing by the driver.
Google search "Google Swift congestion control".
next prev parent reply other threads:[~2023-01-11 18:46 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-01-11 14:34 [RFC PATCH net-next 0/7] NIC driver Rx ring ECN jgh
2023-01-11 14:34 ` [RFC PATCH 1/7] net: NIC driver Rx ring ECN: skbuff and tcp support jgh
2023-01-11 14:34 ` [RFC PATCH 2/7] net: NIC driver Rx ring ECN: stats counter jgh
2023-01-11 14:34 ` [RFC PATCH 3/7] drivers: net: xgene: NIC driver Rx ring ECN jgh
2023-01-11 14:34 ` [RFC PATCH 4/7] drivers: net: bnx2x: " jgh
2023-01-11 14:34 ` [RFC PATCH 5/7] " jgh
2023-01-11 14:34 ` [RFC PATCH 6/7] drivers: net: bnx2: " jgh
2023-01-11 14:34 ` [RFC PATCH 7/7] " jgh
2023-01-11 18:46 ` Jakub Kicinski [this message]
2023-01-12 14:06 ` [RFC PATCH net-next 0/7] " Jeremy Harris
2023-01-13 0:09 ` Jakub Kicinski
2023-01-19 17:05 ` Jeremy Harris
2023-01-19 17:20 ` Jakub Kicinski
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