From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]) by canuck.infradead.org with esmtps (Exim 4.72 #1 (Red Hat Linux)) id 1PJd07-0008BY-N4 for kexec@lists.infradead.org; Sat, 20 Nov 2010 02:16:28 +0000 From: Ben Hutchings In-Reply-To: <20101119214410.087440440@clark.site> References: <20101119214410.087440440@clark.site> Date: Sat, 20 Nov 2010 02:16:12 +0000 Message-ID: <1290219372.3818.113.camel@localhost> Mime-Version: 1.0 Subject: Re: [Stable-review] [08/45] mm, x86: Saving vmcore with non-lazy freeing of vmas List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1267143167==" Sender: kexec-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=infradead.org@lists.infradead.org To: Greg KH Cc: akpm@linux-foundation.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, stable@kernel.org, stable-review@kernel.org, Ingo Molnar , torvalds@linux-foundation.org, Cliff Wickman , alan@lxorguk.ukuu.org.uk --===============1267143167== Content-Type: multipart/signed; micalg="pgp-sha1"; protocol="application/pgp-signature"; boundary="=-xspl/jbONpB3o2YLR3IV" --=-xspl/jbONpB3o2YLR3IV Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Fri, 2010-11-19 at 13:42 -0800, Greg KH wrote: > 2.6.32-stable review patch. If anyone has any objections, please let us = know. >=20 > ------------------ >=20 > From: Cliff Wickman >=20 > commit 3ee48b6af49cf534ca2f481ecc484b156a41451d upstream. >=20 > During the reading of /proc/vmcore the kernel is doing > ioremap()/iounmap() repeatedly. And the buildup of un-flushed > vm_area_struct's is causing a great deal of overhead. (rb_next() > is chewing up most of that time). >=20 > This solution is to provide function set_iounmap_nonlazy(). It > causes a subsequent call to iounmap() to immediately purge the > vma area (with try_purge_vmap_area_lazy()). >=20 > With this patch we have seen the time for writing a 250MB > compressed dump drop from 71 seconds to 44 seconds. [...] Useful, but it doesn't seem to meet the criteria for stable updates. Ben. --=20 Ben Hutchings Once a job is fouled up, anything done to improve it makes it worse. --=-xspl/jbONpB3o2YLR3IV Content-Type: application/pgp-signature; name="signature.asc" Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) iQIVAwUATOcvX+e/yOyVhhEJAQLBBw//dsjK9xRK3e58u8WqfSuyof+7PsXrJ/93 peiH+cwN8TDjap8Sy6mL8NT6X93JIbpugcKmW5s7UxFcU8L2y3P3D7INPcQWtIJE hiv9qPp8432ccQT4bhV2g2Uk6tQ2hyr59TZHh3gvoCRCnlD6Mr1x1ZyGNbxNGJtZ 5BhPLOrJ85ghp4ok8b9CAhdpEDvbIUM4rbIf8qCf7yM8rtn6+uhO0NxlbdmQ8dfT kOte1EyUkL8/88FbVxSnbwSWTtDRdSR5XISh+MPUxZqRrjthuPvLtMVLUNnl8f3T zY2yHC2vZ71cOoysv8bOBm9cmYewB5KN8nYh6xL6EDIR5Albb2Uek1YtPDOnZ6nD iPzYxi1uOV96o09eztpkjXietRkyPzgkc+eAKA1OkxyX+87OWgWJA6lsq4dCR7TD wUE06Hjr7/2dWlerK6ZuRbl2Zf54CteuVYO38Ro1VbmFa6PfMTIiGJciMln0Hw84 u/y6C3ImwaNdVO6s1e0PHLQknDg8CjMpQfPxD/N6apckFIfLijNR0MLwNnKF32ZB QdUQizx6JLiSBYXgxYkjHyXeOMvhMA049BgAdPi0CSsz66uy3gBozBTLiVy7pAmZ FSHhIqlN6CrGWj8kUggWjqSP+g+0SY9ua9QmFnzZ5UdK4R+i20MWJzNBtXwKJBe2 jqk10YKfsYg= =72pV -----END PGP SIGNATURE----- --=-xspl/jbONpB3o2YLR3IV-- --===============1267143167== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec --===============1267143167==--