From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arjan van de Ven Subject: Re: Scsi midlayer question Date: Fri, 16 Jul 2004 20:08:04 +0200 Sender: linux-scsi-owner@vger.kernel.org Message-ID: <1090001284.2805.10.camel@laptop.fenrus.com> References: <47F3C2BE74738E4683574107469DFA204CC4FA@XYUSEX01.xyus.xyratex.com> Reply-To: arjanv@redhat.com Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="=-KznSmDd24Iv1cKhZb2H0" Return-path: Received: from mx1.redhat.com ([66.187.233.31]:56715 "EHLO mx1.redhat.com") by vger.kernel.org with ESMTP id S266567AbUGPSLu (ORCPT ); Fri, 16 Jul 2004 14:11:50 -0400 In-Reply-To: <47F3C2BE74738E4683574107469DFA204CC4FA@XYUSEX01.xyus.xyratex.com> List-Id: linux-scsi@vger.kernel.org To: Frank Borich Cc: linux-scsi@vger.kernel.org --=-KznSmDd24Iv1cKhZb2H0 Content-Type: multipart/mixed; boundary="=-umPZBkRYmS+w84hYgNAF" --=-umPZBkRYmS+w84hYgNAF Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On Fri, 2004-07-16 at 19:55, Frank Borich wrote: > I can see from a fibre channel trace that my 1 MB I/O transfers are > getting cut up into little chunks. > Is there any options that can be set when loading the scsi mid layer as > a module that will improve > io performance or prevent this breakdown for the sg,sd, or even raw > drivers. I am not a driver developer=20 > so please excuse my ignorance here. Any info or points in the right > direction would be greatly apprecited. > I am using the 2.4.20 kernel. =20 try the patch I attached. --=-umPZBkRYmS+w84hYgNAF Content-Disposition: attachment; filename=w.patch Content-Transfer-Encoding: base64 Content-Type: text/x-patch; name=w.patch; charset=UTF-8 LS0tIGxpbnV4L21tL3BhZ2VfYWxsb2MuYy5vcmcJMjAwNC0wNi0yNCAxNzozNjoyMi4wNDI0NjA5 MjAgKzAyMDANCisrKyBsaW51eC9tbS9wYWdlX2FsbG9jLmMJMjAwNC0wNi0yNCAxNzozODoxMi4z NjE2ODk4NDggKzAyMDANCkBAIC0yODIsMTUgKzI4MiwxMyBAQA0KIAl1bnNpZ25lZCBsb25nIHNp emUgPSAxIDw8IGhpZ2g7DQogDQogCXdoaWxlIChoaWdoID4gbG93KSB7DQotCQlpZiAoQkFEX1JB TkdFKHpvbmUscGFnZSkpDQotCQkJQlVHKCk7DQogCQlhcmVhLS07DQogCQloaWdoLS07DQogCQlz aXplID4+PSAxOw0KLQkJbGlzdF9hZGQoJihwYWdlKS0+bGlzdCwgJihhcmVhKS0+ZnJlZV9saXN0 KTsNCi0JCU1BUktfVVNFRChpbmRleCwgaGlnaCwgYXJlYSk7DQotCQlpbmRleCArPSBzaXplOw0K LQkJcGFnZSArPSBzaXplOw0KKwkJaWYgKEJBRF9SQU5HRSh6b25lLCZwYWdlW3NpemVdKSkNCisJ CQlCVUcoKTsNCisJCWxpc3RfYWRkKCZwYWdlW3NpemVdLmxpc3QsICYoYXJlYSktPmZyZWVfbGlz dCk7DQorCQlNQVJLX1VTRUQoaW5kZXggKyBzaXplLCBoaWdoLCBhcmVhKTsNCiAJfQ0KIAlpZiAo QkFEX1JBTkdFKHpvbmUscGFnZSkpDQogCQlCVUcoKTsNCg== --=-umPZBkRYmS+w84hYgNAF-- --=-KznSmDd24Iv1cKhZb2H0 Content-Type: application/pgp-signature; name=signature.asc Content-Description: This is a digitally signed message part -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (GNU/Linux) iD8DBQBA+BmExULwo51rQBIRAkkjAJ47LgkWBcPNBRDZBWHglZctmrrjBQCggu0e z88wUI2HWrRIcWrBVcDIfBo= =lV0E -----END PGP SIGNATURE----- --=-KznSmDd24Iv1cKhZb2H0--