From: Simon Horman <horms@kernel.org>
To: Haiyang Zhang <haiyangz@microsoft.com>
Cc: linux-hyperv@vger.kernel.org, netdev@vger.kernel.org,
kys@microsoft.com, davem@davemloft.net, edumazet@google.com,
kuba@kernel.org, pabeni@redhat.com, corbet@lwn.net,
dsahern@kernel.org, ncardwell@google.com, ycheng@google.com,
kuniyu@amazon.com, morleyd@google.com, mfreemon@cloudflare.com,
mubashirq@google.com, linux-doc@vger.kernel.org,
weiwan@google.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH net-next,v3] tcp: Set pingpong threshold via sysctl
Date: Mon, 16 Oct 2023 11:10:48 +0200 [thread overview]
Message-ID: <20231016091048.GG1501712@kernel.org> (raw)
In-Reply-To: <1697056244-21888-1-git-send-email-haiyangz@microsoft.com>
On Wed, Oct 11, 2023 at 01:30:44PM -0700, Haiyang Zhang wrote:
> TCP pingpong threshold is 1 by default. But some applications, like SQL DB
> may prefer a higher pingpong threshold to activate delayed acks in quick
> ack mode for better performance.
>
> The pingpong threshold and related code were changed to 3 in the year
> 2019 in:
> commit 4a41f453bedf ("tcp: change pingpong threshold to 3")
> And reverted to 1 in the year 2022 in:
> commit 4d8f24eeedc5 ("Revert "tcp: change pingpong threshold to 3"")
>
> There is no single value that fits all applications.
> Add net.ipv4.tcp_pingpong_thresh sysctl tunable, so it can be tuned for
> optimal performance based on the application needs.
>
> Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
> ---
> v3: Updated doc as suggested by Neal Cardwell.
> Updated variable location in struct netns_ipv4 as suggested by Kuniyuki
> Iwashima.
>
> v2: Make it per-namesapce setting, and other updates suggested by Neal Cardwell,
> and Kuniyuki Iwashima.
Thanks,
this looks clean to me. It seems to address the review of v2.
And keeps the knob as syctl as discussed in v2.
Reviewed-by: Simon Horman <horms@kernel.org>
next prev parent reply other threads:[~2023-10-16 9:10 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-10-11 20:30 [PATCH net-next,v3] tcp: Set pingpong threshold via sysctl Haiyang Zhang
2023-10-16 9:10 ` Simon Horman [this message]
2023-10-16 11:40 ` Eric Dumazet
2023-10-16 16:17 ` Neal Cardwell
2023-10-16 16:49 ` Kuniyuki Iwashima
2023-10-16 22:30 ` patchwork-bot+netdevbpf
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20231016091048.GG1501712@kernel.org \
--to=horms@kernel.org \
--cc=corbet@lwn.net \
--cc=davem@davemloft.net \
--cc=dsahern@kernel.org \
--cc=edumazet@google.com \
--cc=haiyangz@microsoft.com \
--cc=kuba@kernel.org \
--cc=kuniyu@amazon.com \
--cc=kys@microsoft.com \
--cc=linux-doc@vger.kernel.org \
--cc=linux-hyperv@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mfreemon@cloudflare.com \
--cc=morleyd@google.com \
--cc=mubashirq@google.com \
--cc=ncardwell@google.com \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=weiwan@google.com \
--cc=ycheng@google.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.