From: Jakub Kicinski <kuba@kernel.org>
To: Paolo Abeni <pabeni@redhat.com>
Cc: Saeed Mahameed <saeed@kernel.org>,
netdev@vger.kernel.org, Jonathan Corbet <corbet@lwn.net>,
"David S. Miller" <davem@davemloft.net>,
Shuah Khan <shuah@kernel.org>,
linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org,
Marcelo Tosatti <mtosatti@redhat.com>,
Daniel Borkmann <daniel@iogearbox.net>
Subject: Re: [PATCH net-next v2 0/3] net: introduce rps_default_mask
Date: Mon, 30 Jan 2023 13:52:21 -0800 [thread overview]
Message-ID: <20230130135221.3deeed6c@kernel.org> (raw)
In-Reply-To: <6758c48d926845ae323a68fb4649fb982e2321c4.camel@redhat.com>
On Mon, 30 Jan 2023 10:25:34 +0100 Paolo Abeni wrote:
> Let me try for a moment to revive this old thread.
>
> Tha series proposed a new sysctl know to implement a global/default rps
> mask applying to all the network devices as a way to simplify some RT
> setups. It has been rejected as the required task is doable in user-
> space.
>
> Currently the orchestration infrastructure does that, setting the per
> device, per queue rps mask and CPU isolation.
>
> The above leads to a side problem: when there are lot of netns/devices
> with several queues, even a reasonably optimized user-space solution
> takes a relevant amount of time to traverse the relevant sysfs dirs and
> do I/O on them. Overall the additional time required is very
> measurable, easily ranging in seconds.
>
> The default_rps_mask would basically kill that overhead.
>
> Is the above a suitable use case?
Alright, thanks for trying the user space fix.
prev parent reply other threads:[~2023-01-30 21:52 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-30 11:16 [PATCH net-next v2 0/3] net: introduce rps_default_mask Paolo Abeni
2020-10-30 11:16 ` [PATCH net-next v2 1/3] net/sysctl: factor-out netdev_rx_queue_set_rps_mask() helper Paolo Abeni
2020-10-30 11:16 ` [PATCH net-next v2 2/3] net/core: introduce default_rps_mask netns attribute Paolo Abeni
2020-10-30 11:16 ` [PATCH net-next v2 3/3] self-tests: introduce self-tests for RPS default mask Paolo Abeni
2020-11-02 22:54 ` [PATCH net-next v2 0/3] net: introduce rps_default_mask Jakub Kicinski
2020-11-02 23:27 ` Saeed Mahameed
2020-11-03 15:22 ` Paolo Abeni
2020-11-03 16:52 ` Jakub Kicinski
2020-11-04 17:36 ` Paolo Abeni
2020-11-04 18:18 ` Marcelo Tosatti
2020-11-04 19:42 ` Jakub Kicinski
2023-01-30 9:25 ` Paolo Abeni
2023-01-30 21:52 ` Jakub Kicinski [this message]
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