From: Andi Kleen <ak@suse.de>
To: John Heffner <jheffner@psc.edu>
Cc: Stephen Hemminger <shemminger@osdl.org>, netdev@vger.kernel.org
Subject: Re: [PATCH] Bound TSO defer time (resend)
Date: Wed, 18 Oct 2006 17:37:36 +0200 [thread overview]
Message-ID: <200610181737.36135.ak@suse.de> (raw)
In-Reply-To: <45345999.4000300@psc.edu>
On Tuesday 17 October 2006 06:18, John Heffner wrote:
> Stephen Hemminger wrote:
> > On Mon, 16 Oct 2006 20:53:20 -0400 (EDT)
> > John Heffner <jheffner@psc.edu> wrote:
>
> >> This patch limits the amount of time you will defer sending a TSO segment
> >> to less than two clock ticks, or the time between two acks, whichever is
> >> longer.
>
> >
> > Okay, but doing any timing on clock ticks makes the behavior dependent
> > on the value of HZ which doesn't seem desirable. Should this be based
> > on RTT or a real-time values?
>
> It would be nice to use a high res clock so you don't depend on HZ, but
> this is still expensive on most SMP arch's as I understand it.
You can always use xtime. It doesn't have better solution than jiffies
though, but it gives you real time.
Drawback is that there is some work towards tickless kernels and with
that xtime will be more expensive again. But hopefully not by that much.
-Andi
next prev parent reply other threads:[~2006-10-18 15:37 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-10-17 0:53 [PATCH] Bound TSO defer time (resend) John Heffner
2006-10-17 3:20 ` Stephen Hemminger
2006-10-17 4:18 ` John Heffner
2006-10-17 5:35 ` David Miller
2006-10-17 12:22 ` John Heffner
2006-10-19 3:39 ` David Miller
2006-10-17 12:58 ` [PATCH] [NET] Size listen hash tables using backlog hint Eric Dumazet Hi
2006-10-18 7:38 ` [PATCH] [NET] inet_peer : group together avl_left, avl_right, v4daddr to speedup lookups on some CPUS Eric Dumazet
2006-10-18 16:35 ` [PATCH] [NET] reduce per cpu ram used for loopback stats Eric Dumazet
2006-10-18 17:00 ` [PATCH, resent] " Eric Dumazet
2006-10-19 3:53 ` David Miller
2006-10-19 3:53 ` [PATCH] " David Miller
2006-10-19 3:44 ` [PATCH] [NET] inet_peer : group together avl_left, avl_right, v4daddr to speedup lookups on some CPUS David Miller
2006-10-19 10:57 ` Eric Dumazet
2006-10-19 15:45 ` [PATCH] [NET] One NET_INC_STATS() could be NET_INC_STATS_BH in tcp_v4_err() Eric Dumazet
2006-10-20 7:22 ` David Miller
2006-10-20 14:21 ` Arnaldo Carvalho de Melo
2006-10-20 7:28 ` [PATCH] [NET] inet_peer : group together avl_left, avl_right, v4daddr to speedup lookups on some CPUS David Miller
2006-10-19 3:31 ` [PATCH] [NET] Size listen hash tables using backlog hint David Miller
2006-10-19 4:54 ` Stephen Hemminger
2006-10-19 5:08 ` David Miller
2006-10-19 5:12 ` Eric Dumazet
2006-10-19 6:12 ` David Miller
2006-10-19 6:34 ` Eric Dumazet
2006-10-19 6:57 ` David Miller
2006-10-19 8:29 ` Eric Dumazet
2006-10-19 8:41 ` David Miller
2006-10-19 9:11 ` Eric Dumazet
2006-10-19 9:27 ` Eric Dumazet
2006-10-20 7:27 ` David Miller
2006-10-18 15:37 ` Andi Kleen [this message]
2006-10-18 16:40 ` [PATCH] Bound TSO defer time (resend) Stephen Hemminger
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=200610181737.36135.ak@suse.de \
--to=ak@suse.de \
--cc=jheffner@psc.edu \
--cc=netdev@vger.kernel.org \
--cc=shemminger@osdl.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).