From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: [patch 1/1] raid5: speedup sync_request processing Date: Tue, 10 Jun 2014 11:10:23 +1000 Message-ID: <20140610111023.7a2e6ecd@notabene.brown> References: Mime-Version: 1.0 Content-Type: multipart/signed; micalg=PGP-SHA1; boundary="Sig_/+8bMCJVgV2JQChVy9mEJi8t"; protocol="application/pgp-signature" Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Eivind Sarto Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids --Sig_/+8bMCJVgV2JQChVy9mEJi8t Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: quoted-printable On Mon, 9 Jun 2014 17:06:19 -0700 Eivind Sarto wrot= e: > Ignore previous email. Forgot to attach patch. >=20 > This is a trivial patch that improves rebuild/resync speed of raid5 array= s. > Instead of having the resync-thread handle the stripe, it now just sets S= TRIPE_HANDLE and > releases the stripe. Allowing the resync-thread to return immediately an= d schedule more operations. >=20 > The speedup will increase with more drives in the array. And it will inc= rease further if additional > kworker threads are enabled. But, it improves with just the default raid= 5d() running. >=20 > Note: I posted this patch a while back, but nothing happened. Not accept= ed, not rejected. >=20 > Trying one more time. >=20 > -eivind I looked through my mail and found you posted much the same patch on 11th February. I replied as below. You never resent (or if you did, I never got it). You did reply with some numbers, but that isn't the same as resubmitting the patch with a proper description at the top. Your new patch does mention some performance numbers in the comment so that= I a lot better. I've applied it. Thanks, NeilBrown Hi, thanks for the patch. When you include a patch as an attachment, I find it easier to work with if it is "text/plain" rather than "application/octet-stream". As your patch is justified as a performance improvement, please include some measurements together with a rough description of the hardware (one or two sentences). Also, the performance improvement requires that multi-threading is enabled, which isn't the default. Please measure the effect of the patch when multi-threading not enabled. Maybe we should make the change you suggest be conditional on threading being enabled, but we can't know without numbers. Thanks, NeilBrown --Sig_/+8bMCJVgV2JQChVy9mEJi8t Content-Type: application/pgp-signature; name=signature.asc Content-Disposition: attachment; filename=signature.asc -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIVAwUBU5Za/znsnt1WYoG5AQKyNg/8C7HHN4AtUzc3W92+V/jZGUOcY/fwo/xz X+u00YGe7ic8V167Bk2Y62zh9hqGOjkhwITzoHEeKAq56DNNNBnugHUfr3X4gMgK lEU2iHstJ0jPBdP5Od+YLqffKef2/iIBkOVcpyNeYir1EbsE9HgLXxuoaY2nA9Ji iD1Qk3WIQMItHiY8PcL5ruDom5jFMKPjEVU6bhI1RrX5eAXa2UAtBjIMtoPhEkHc cw3UZZJrjQtJZkyJpxAVy+xktese+fYu0GP8uF0enFpe315D8PoG5kqgx/Z7o2Do vOJfjH4LJ5Kn5RBEMr2c7Qn044yu/MTs/XdpbbzGcfM8O8QQqEz0OGxVFHN11/Z8 yD5cxUbjELTWelxbw6dR8K3sheLOyD7UESdWZNs1Z2W0ivRgxVpLnFPyvDQC6Wnr n86spZkoDfjLqtMKn2drBCEB4qdBrD5fas64S7gWPnm3eXjfTutCU6r1PQEcLS9C EloSzqsBGLmWmb7WYbeumVf6tvMIigsHEMlFeqnaUVrNZeem2ZwR6fbeAm4JAcXt uEzUWISZrwIvvFW5/tuCigBZPVRVVOfzkNyT+WGNrQXAQ5RdcqRH15fEuvUlmd+S rFuPfqwMKLrZZ03VQdR3mtQDmwa/jGYR+UNb34eWFCWe7e5VC1Jf/E5F4JVKokgh 9wuVU8yOH9M= =ZieU -----END PGP SIGNATURE----- --Sig_/+8bMCJVgV2JQChVy9mEJi8t--