From: Fabio Riccardi <fabio@chromium.com>
To: unlisted-recipients:; (no To-header on input)@localhost.localdomain
Cc: linux-kernel@vger.kernel.org
Subject: Re: X15 alpha release: as fast as TUX but in user space (fwd)
Date: Wed, 02 May 2001 13:55:53 -0700 [thread overview]
Message-ID: <3AF07459.8D8ECD8E@chromium.com> (raw)
In-Reply-To: <Pine.LNX.4.33.0104290914260.14261-100000@twinlark.arctic.org> <200104292116.f3TLGhu07016@pachyderm.pa.dec.com> <20010502211800.X805@mea-ext.zmailer.org> <9cpnfj$ms3$1@penguin.transmeta.com>
>From my experience system calls are not an issue.
What costs a lot is moving data around, since modern CPUs spend most of their
time in memory/bus wait cycles...
- Fabio
Linus Torvalds wrote:
> >I think that applies to all really high-performance servers.
>
> Note that it is definitely not always true.
>
> Linux system calls are reasonably light-weight. And sometimes trying to
> avoid them ends up beaing _more_ work - because you might have to worry
> about synchronization and cache coherency in user mode.
>
> So the rule should be "avoid _unnecessary_ system calls".
>
> Linus
> -
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
next prev parent reply other threads:[~2001-05-02 20:52 UTC|newest]
Thread overview: 53+ messages / expand[flat|nested] mbox.gz Atom feed top
2001-04-28 15:52 X15 alpha release: as fast as TUX but in user space (fwd) Ingo Molnar
2001-04-28 19:53 ` Andi Kleen
2001-04-28 22:56 ` Richard Gooch
2001-04-29 5:13 ` H. Peter Anvin
2001-04-29 11:14 ` Jeff Garzik
2001-04-29 11:27 ` David S. Miller
2001-04-29 13:32 ` Ingo Oeser
2001-04-29 18:48 ` Richard Gooch
2001-04-29 18:55 ` Gregory Maxwell
2001-04-29 19:02 ` Richard Gooch
2001-04-29 19:47 ` Gregory Maxwell
2001-04-29 19:54 ` Richard Gooch
2001-04-29 20:11 ` Ingo Oeser
2001-04-29 20:18 ` Gregory Maxwell
2001-04-29 22:20 ` Richard Gooch
2001-04-30 0:13 ` Andrea Arcangeli
2001-04-29 20:45 ` Arjan van de Ven
2001-04-29 22:18 ` Richard Gooch
2001-04-30 16:46 ` Alan Cox
2001-04-29 19:38 ` Jamie Lokier
2001-04-29 23:53 ` Andrea Arcangeli
2001-04-29 16:21 ` dean gaudet
2001-04-29 20:19 ` H. Peter Anvin
2001-04-29 22:29 ` Richard Gooch
2001-04-29 21:16 ` Jim Gettys
2001-04-29 21:40 ` H. Peter Anvin
2001-04-29 21:47 ` Jim Gettys
2001-05-02 18:18 ` Matti Aarnio
2001-05-02 19:34 ` Linus Torvalds
2001-05-02 20:55 ` Fabio Riccardi [this message]
2001-04-30 7:02 ` David S. Miller
2001-04-30 7:29 ` H. Peter Anvin
2001-04-30 7:51 ` David S. Miller
2001-04-30 14:56 ` Jonathan Lundell
2001-04-30 8:42 ` Pavel Machek
2001-05-03 7:13 ` Kai Henningsen
2001-05-03 7:44 ` Keith Owens
2001-05-03 10:37 ` Ingo Oeser
2001-05-03 15:44 ` Gregory Maxwell
2001-05-07 19:04 ` Pavel Machek
2001-05-03 9:37 ` Alan Cox
2001-05-07 19:03 ` vsyscalls [was Re: X15 alpha release: as fast as TUX but in user space (fwd)] Pavel Machek
2001-05-03 12:23 ` X15 alpha release: as fast as TUX but in user space (fwd) Helge Hafting
2001-05-03 19:09 ` Pavel Machek
2001-05-03 19:50 ` agrawal
2001-05-07 19:07 ` vsyscallRe: " Pavel Machek
2001-05-03 20:19 ` Alan Cox
2001-05-03 20:41 ` Gregory Maxwell
2001-05-04 8:06 ` Pavel Machek
2001-05-04 17:31 ` dean gaudet
2001-05-04 8:43 ` bert hubert
2001-05-02 10:52 ` Andi Kleen
2001-05-02 10:53 ` Ingo Molnar
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