From: Tony Luck <tony.luck@gmail.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
"linux-mm@kvack.org" <linux-mm@kvack.org>
Subject: Re: [PATCHv2 0/3] Find mirrored memory, use for boot time allocations
Date: Fri, 8 May 2015 16:41:23 -0700 [thread overview]
Message-ID: <CA+8MBbJz79aSNRmfRJ2aEisQz10+zURfeu=GiHUofYDQyviP=w@mail.gmail.com> (raw)
In-Reply-To: <20150508134901.e3e7585b359b073253788c22@linux-foundation.org>
On Fri, May 8, 2015 at 1:49 PM, Andrew Morton <akpm@linux-foundation.org> wrote:
> What I mean is: allow userspace to consume ZONE_MIRROR memory because
> we can snatch it back if it is needed for kernel memory.
For suitable interpretations of "snatch it back" ... if there is none
free in a GFP_NOWAIT request, then we are doomed. But we
could maintain some high/low watermarks to arrange the snatching
when mirrored memory is getting low, rather than all the way out.
It's worth a look - but perhaps at phase three. It would make life
a bit easier for people to get the right amount of mirror. If they
guess too high they are still wasting some memory because
every mirrored page has two pages in DIMM. But without this
sort of trick all the extra mirrored memory would be totally wasted.
-Tony
--
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>
next prev parent reply other threads:[~2015-05-08 23:41 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-05-08 16:44 Tony Luck
2015-05-07 22:17 ` [PATCHv2 1/3] mm/memblock: Add extra "flags" to memblock to allow selection of memory based on attribute Tony Luck
2015-05-07 22:18 ` [PATCHv2 2/3] mm/memblock: Allocate boot time data structures from mirrored memory Tony Luck
2015-05-07 22:19 ` [PATCHv2 3/3] x86, mirror: x86 enabling - find mirrored memory ranges Tony Luck
2015-05-08 20:03 ` [PATCHv2 0/3] Find mirrored memory, use for boot time allocations Andrew Morton
2015-05-08 20:38 ` Tony Luck
2015-05-08 20:49 ` Andrew Morton
2015-05-08 23:41 ` Tony Luck [this message]
2015-05-19 3:01 ` Xishi Qiu
2015-05-19 4:48 ` Tony Luck
2015-05-19 6:37 ` Xishi Qiu
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='CA+8MBbJz79aSNRmfRJ2aEisQz10+zURfeu=GiHUofYDQyviP=w@mail.gmail.com' \
--to=tony.luck@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.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