From: Nick Piggin <nickpiggin@yahoo.com.au>
To: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Cc: Rik van Riel <riel@redhat.com>,
akpm@linux-foundation.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] undo the brd.c part of ramfs-and-ram-disk-pages-are-unevictable.patch
Date: Fri, 13 Jun 2008 05:08:19 +1000 [thread overview]
Message-ID: <200806130508.19661.nickpiggin@yahoo.com.au> (raw)
In-Reply-To: <1213297257.6240.15.camel@lts-notebook>
On Friday 13 June 2008 05:00, Lee Schermerhorn wrote:
> On Thu, 2008-06-12 at 13:53 -0400, Rik van Riel wrote:
> > Undo the brd.c part of ramfs-and-ram-disk-pages-are-unevictable.patch.
> > The brd pages do not live on the LRU at all, so there is no need to
> > play these tricks.
>
> Does this mean that these pages cannot be migrated? E.g., to evacuate
> memory for hotplug? Looks like all paths to migrate_pages() construct a
> list of pages to migrate by isolating them from the lru
> [isolate_lru_page()]. Any pages not found in the lru are skipped.
Yes. They have nothing to do with user pages or pagecache pages at all
really. brd is now a properly layered block device driver that does not
know anything about buffer cache ;)
You can think of the pages it allocates as completely private, and they
are used to implement the backing store for the block device.
The vm/fs layers will instantiate buffer cache over this device, which
is reclaimable.
prev parent reply other threads:[~2008-06-12 19:08 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2008-06-12 17:53 Rik van Riel
2008-06-12 19:00 ` Lee Schermerhorn
2008-06-12 19:05 ` Rik van Riel
2008-06-12 19:08 ` Nick Piggin [this message]
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=200806130508.19661.nickpiggin@yahoo.com.au \
--to=nickpiggin@yahoo.com.au \
--cc=Lee.Schermerhorn@hp.com \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--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
all inboxes | Powered by JetHome®