public inbox for linux-kernel@vger.kernel.org
 help / color / mirror / Atom feed
From: Edgar Toernig <froese@gmx.de>
To: Michal Moskal <malekith@pld.org.pl>
Cc: linux-kernel@vger.kernel.org
Subject: Re: strange TCP stack behiviour with write()es in pieces
Date: Wed, 02 Jan 2002 19:26:15 +0100	[thread overview]
Message-ID: <3C3350C7.D11110A@gmx.de> (raw)
In-Reply-To: <20020102162806.GA29399@ep09.kernel.pl>

Michal Moskal wrote:
> 
> So, it occurs in programs doing packet communication over TCP, when
> peer waits for a packet to send an answer. If they send data with two
> write() calls (for example to write packet header and packet data),
> the performance dramaticly decrases (down to exactly 100 (2.2.19)
> or 25 (2.4.[57]) packet exchanges per second on x86, from several
> thousands. 100 seems to be related to HZ variable, see also AXP results,
> where HZ is 10 times bigger).

Try disabling the nagle algorithm:

        int i = 1;
        if (setsockopt(fd, SOL_TCP, TCP_NODELAY, &i, sizeof(i)) == -1)
            perror("TCP_NODELAY");

Ciao, ET.

  reply	other threads:[~2002-01-02 18:27 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-01-02 16:28 strange TCP stack behiviour with write()es in pieces Michal Moskal
2002-01-02 18:26 ` Edgar Toernig [this message]
2002-01-02 19:46 ` dean gaudet
2002-01-02 20:21   ` Richard B. Johnson
2002-01-02 21:49 ` David Schwartz
  -- strict thread matches above, loose matches on Subject: below --
2002-01-03 13:22 Michal Moskal
2002-01-03 20:43 ` David Schwartz

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=3C3350C7.D11110A@gmx.de \
    --to=froese@gmx.de \
    --cc=linux-kernel@vger.kernel.org \
    --cc=malekith@pld.org.pl \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox