public inbox for linux-ia64@vger.kernel.org
 help / color / mirror / Atom feed
From: Dave Hansen <haveblue@us.ibm.com>
To: linux-ia64@vger.kernel.org
Subject: RE: [patch 0/4] ia64 SPARSEMEM
Date: Tue, 31 May 2005 18:14:22 +0000	[thread overview]
Message-ID: <1117563262.20180.37.camel@localhost> (raw)
In-Reply-To: <20050523175031.GC2783@localhost.localdomain>

On Tue, 2005-05-31 at 10:55 -0700, Luck, Tony wrote:
> What are the other benefits of SPARSEMEM that I'm missing?

* The same implementation works everywhere, on every architecture.
* It has good tlb behavior.
* It is faster and has a lower icache footprint than existing
  discontigmem implementations.
* On a theoretical 16TB ppc64 system with 16MB sections, the overhead of
  the mem_section[] table is 8MB.

Also, nothing seriously confines us to a flat array of mem_sections,
that's just the only implementation right now.  The pagetables that are
walked in the TLB miss handler (for vmem_map[]) could just as easily be
a set of two-level mem_section tables that are walked in software.  That
just adds an extra load to the pfn_to_page() path.  Plus, if somebody
does this, all sparsemem architectures can benefit.

-- Dave


  parent reply	other threads:[~2005-05-31 18:14 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-05-23 17:50 [patch 0/4] ia64 SPARSEMEM Bob Picco
2005-05-24  3:29 ` David Mosberger
2005-05-24 14:33 ` Bob Picco
2005-05-24 16:27 ` Bob Picco
2005-05-26  0:32 ` Luck, Tony
2005-05-26 20:09 ` David Mosberger
2005-05-26 20:54 ` Bob Picco
2005-05-26 21:02 ` Dave Hansen
2005-05-26 21:34 ` Luck, Tony
2005-05-26 21:44 ` Jack Steiner
2005-05-26 21:51 ` Bob Picco
2005-05-26 22:03 ` Luck, Tony
2005-05-26 22:04 ` Bob Picco
2005-05-27  5:14 ` Yasunori Goto
2005-05-27 10:35 ` Bob Picco
2005-05-27 16:23 ` David Mosberger
2005-05-27 22:04 ` Jack Steiner
2005-05-30  0:18 ` KAMEZAWA Hiroyuki
2005-05-31 17:55 ` Luck, Tony
2005-05-31 18:14 ` Dave Hansen [this message]
2005-05-31 18:15 ` Jack Steiner
2005-05-31 21:41 ` Luck, Tony
2005-05-31 21:58 ` Dave Hansen
2005-06-01  1:37 ` Bob Picco
2005-06-01  9:14 ` Andy Whitcroft
2005-06-01 22:48 ` David Mosberger

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=1117563262.20180.37.camel@localhost \
    --to=haveblue@us.ibm.com \
    --cc=linux-ia64@vger.kernel.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