All of lore.kernel.org
 help / color / mirror / Atom feed
From: Florian Westphal <fw@strlen.de>
To: <netdev@vger.kernel.org>
Cc: edumazet@google.com
Subject: [PATCH net-next 0/2] tcp: re-add header prediction
Date: Wed, 30 Aug 2017 19:24:56 +0200	[thread overview]
Message-ID: <20170830172458.18544-1-fw@strlen.de> (raw)

Eric reported a performance regression caused by header prediction
removal.

We now call tcp_ack() much more frequently, for some workloads
this brings in enough cache line misses to become noticeable.

We could possibly still kill HP provided we find a different
way to suppress unneeded tcp_ack, but given we're late in
the cycle it seems preferable to revert.

             reply	other threads:[~2017-08-30 17:24 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-30 17:24 Florian Westphal [this message]
2017-08-30 17:24 ` [PATCH net-next 1/2] tcp: Revert "tcp: remove CA_ACK_SLOWPATH" Florian Westphal
2017-08-30 17:24 ` [PATCH net-next 2/2] tcp: Revert "tcp: remove header prediction" Florian Westphal
2017-08-30 18:20 ` [PATCH net-next 0/2] tcp: re-add header prediction David Miller

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=20170830172458.18544-1-fw@strlen.de \
    --to=fw@strlen.de \
    --cc=edumazet@google.com \
    --cc=netdev@vger.kernel.org \
    /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.