From owner-svn-src-stable@FreeBSD.ORG Mon Jun 3 16:22:20 2013 Return-Path: Delivered-To: svn-src-stable@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 69DCFEB2; Mon, 3 Jun 2013 16:22:20 +0000 (UTC) (envelope-from smh@FreeBSD.org) Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:1900:2254:2068::e6a:0]) by mx1.freebsd.org (Postfix) with ESMTP id 424741845; Mon, 3 Jun 2013 16:22:20 +0000 (UTC) Received: from svn.freebsd.org ([127.0.1.70]) by svn.freebsd.org (8.14.7/8.14.7) with ESMTP id r53GMJwu065393; Mon, 3 Jun 2013 16:22:19 GMT (envelope-from smh@svn.freebsd.org) Received: (from smh@localhost) by svn.freebsd.org (8.14.7/8.14.5/Submit) id r53GMJQt065392; Mon, 3 Jun 2013 16:22:19 GMT (envelope-from smh@svn.freebsd.org) Message-Id: <201306031622.r53GMJQt065392@svn.freebsd.org> From: Steven Hartland Date: Mon, 3 Jun 2013 16:22:19 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-9@freebsd.org Subject: svn commit: r251306 - stable/9/sys/geom X-SVN-Group: stable-9 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: svn-src-stable@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: SVN commit messages for all the -stable branches of the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 03 Jun 2013 16:22:20 -0000 Author: smh Date: Mon Jun 3 16:22:19 2013 New Revision: 251306 URL: http://svnweb.freebsd.org/changeset/base/251306 Log: MFC r249930: Added a sysctl to control the maximum size of a delete request Modified: stable/9/sys/geom/geom_dev.c Directory Properties: stable/9/sys/ (props changed) Modified: stable/9/sys/geom/geom_dev.c ============================================================================== --- stable/9/sys/geom/geom_dev.c Mon Jun 3 16:14:24 2013 (r251305) +++ stable/9/sys/geom/geom_dev.c Mon Jun 3 16:22:19 2013 (r251306) @@ -52,6 +52,7 @@ __FBSDID("$FreeBSD$"); #include #include #include +#include #include #include #include @@ -93,6 +94,19 @@ static struct g_class g_dev_class = { .attrchanged = g_dev_attrchanged }; +/* + * We target 262144 (8 x 32768) sectors by default as this significantly + * increases the throughput on commonly used SSD's with a marginal + * increase in non-interruptible request latency. + */ +static uint64_t g_dev_del_max_sectors = 262144; +SYSCTL_DECL(_kern_geom); +SYSCTL_NODE(_kern_geom, OID_AUTO, dev, CTLFLAG_RW, 0, "GEOM_DEV stuff"); +SYSCTL_QUAD(_kern_geom_dev, OID_AUTO, delete_max_sectors, CTLFLAG_RW, + &g_dev_del_max_sectors, 0, "Maximum number of sectors in a single " + "delete request sent to the provider. Larger requests are chunked " + "so they can be interrupted. (0 = disable chunking)"); + static void g_dev_destroy(void *arg, int flags __unused) { @@ -412,17 +426,20 @@ g_dev_ioctl(struct cdev *dev, u_long cmd } while (length > 0) { chunk = length; - if (chunk > 65536 * cp->provider->sectorsize) - chunk = 65536 * cp->provider->sectorsize; + if (g_dev_del_max_sectors != 0 && chunk > + g_dev_del_max_sectors * cp->provider->sectorsize) { + chunk = g_dev_del_max_sectors * + cp->provider->sectorsize; + } error = g_delete_data(cp, offset, chunk); length -= chunk; offset += chunk; if (error) break; /* - * Since the request size is unbounded, the service - * time is likewise. We make this ioctl interruptible - * by checking for signals for each bio. + * Since the request size can be large, the service + * time can be is likewise. We make this ioctl + * interruptible by checking for signals for each bio. */ if (SIGPENDING(td)) break;