linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Anton Blanchard <anton@samba.org>
To: Rik van Riel <riel@redhat.com>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>,
	Eric Dumazet <dada1@cosmosbay.com>,
	linux-kernel <linux-kernel@vger.kernel.org>,
	linux-mm <linux-mm@kvack.org>,
	Ulrich Drepper <drepper@redhat.com>
Subject: Re: [PATCH] make MADV_FREE lazily free memory
Date: Mon, 16 Apr 2007 11:10:39 -0500	[thread overview]
Message-ID: <20070416161039.GA979@kryten> (raw)
In-Reply-To: <461DDE44.2040409@redhat.com>

 
Hi,

> Making the pte clean also needs to clear the hardware writable
> bit on architectures where we do pte dirtying in software.
> 
> If we don't, we would have corruption problems all over the VM,
> for example in the code around pte_clean_one :)
> 
> >But as Linus recently said, even hardware handled faults still
> >take expensive microarchitectural traps.
> 
> Nowhere near as expensive as a full page fault, though...

Unfortunately it will be expensive on architectures that have software
referenced and changed. It would be great if we could just leave them
dirty in the pagetables and transition between a clean and dirty state
via madvise calls, but thats just wishful thinking on my part :)

Anton

--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org.  For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>

  parent reply	other threads:[~2007-04-16 16:10 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-04-11  4:30 Rik van Riel
2007-04-11 22:41 ` Eric Dumazet
2007-04-11 22:56   ` Rik van Riel
2007-04-12  5:44     ` Eric Dumazet
2007-04-12  6:08       ` Nick Piggin
2007-04-12  6:12         ` Nick Piggin
2007-04-12  7:22           ` Rik van Riel
2007-04-12 13:14             ` Nick Piggin
2007-04-12 20:58               ` Rik van Riel
2007-04-13  0:34                 ` Nick Piggin
2007-04-16 16:10             ` Anton Blanchard [this message]
2007-04-16 16:30               ` Jakub Jelinek
2007-04-16 18:39                 ` Anton Blanchard

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=20070416161039.GA979@kryten \
    --to=anton@samba.org \
    --cc=dada1@cosmosbay.com \
    --cc=drepper@redhat.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=nickpiggin@yahoo.com.au \
    --cc=riel@redhat.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox