From owner-freebsd-scsi@freebsd.org Wed Sep 20 21:26:53 2017 Return-Path: Delivered-To: freebsd-scsi@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 30F22E248E8 for ; Wed, 20 Sep 2017 21:26:53 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 1909180C6D for ; Wed, 20 Sep 2017 21:26:53 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id v8KLQqBW091082 for ; Wed, 20 Sep 2017 21:26:52 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-scsi@FreeBSD.org Subject: [Bug 221956] cam iosched: Schedule cam_iosched_ticker() quanta times per second Date: Wed, 20 Sep 2017 21:26:53 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: kern X-Bugzilla-Version: CURRENT X-Bugzilla-Keywords: patch X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: commit-hook@freebsd.org X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-scsi@FreeBSD.org X-Bugzilla-Flags: mfc-stable11? X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-scsi@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: SCSI subsystem List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 20 Sep 2017 21:26:53 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D221956 --- Comment #3 from commit-hook@freebsd.org --- A commit references this bug: Author: imp Date: Wed Sep 20 21:25:56 UTC 2017 New revision: 323831 URL: https://svnweb.freebsd.org/changeset/base/323831 Log: cam iosched: Schedule cam_iosched_ticker() quanta times per second Previously callout_reset() was called with a "ticks" value that was off by one. As a result cam_iosched_ticker() was called a bit too frequently: On systems with hz=3D1000 a quanta value of 200 resulted in ~250 calls and a value of 100 in ~111 calls. For the "queue_depth" and "bandwidth" limiters the difference doesn't matter but the "iops" limiter depends on the scheduling to enforce the correct maximum. PR: 221956 Obtained from: ElectroBSD Submitted by: Fabian Keil Differential Revision: https://reviews.freebsd.org/D12350 Changes: head/sys/cam/cam_iosched.c --=20 You are receiving this mail because: You are the assignee for the bug.=