From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id A766F488FB; Fri, 10 Oct 2025 09:44:14 +0200 (CEST) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 6C9DA402A0; Fri, 10 Oct 2025 09:44:14 +0200 (CEST) Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.10]) by mails.dpdk.org (Postfix) with ESMTP id BADD540285 for ; Fri, 10 Oct 2025 09:44:11 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1760082252; x=1791618252; h=date:from:to:cc:subject:message-id:references: content-transfer-encoding:in-reply-to:mime-version; bh=y2eY3ogwhbtotHOhtytaJMOJodRPtg496qCyamFYM8w=; b=MD69u7jKWiyZxllNTH2oNANvQPH71M9ANlEl1rnSQXbKhN28f2dhQUix wgdTP2OIGpQhioXbbm26ba2MZk3a0YqNWGM+ZSEF9RmBlEId4VfPKsrsj BfeqeXCumbRAwGPaJeawImE0+qj4q7fQuO5K9Gv7Hkvq8b48G7kDssOM1 UM3zI0tUgq5HCz7dBrHzJ6g8BlXALgOUyKPMncSnNbWY3PE/AGtnxg/gg FJxQCzqEegMAd0oJ5fo4XZe5r4l2sNitE4XzArl8zS7ZYFih+9gFjCznT 5COIF1/vH+VO+AxjrFL3/2zgg38OrobkT+7UmYdJAFWjt+6NzRifOQTHq Q==; X-CSE-ConnectionGUID: 8joLqBP2Q7CfyPus4unU+w== X-CSE-MsgGUID: TR8MV59+SYya5CL5D7f6oA== X-IronPort-AV: E=McAfee;i="6800,10657,11577"; a="79743176" X-IronPort-AV: E=Sophos;i="6.19,218,1754982000"; d="scan'208";a="79743176" Received: from fmviesa009.fm.intel.com ([10.60.135.149]) by orvoesa102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Oct 2025 00:44:11 -0700 X-CSE-ConnectionGUID: 86/w8UI7TZ+AtbCx9Cal9g== X-CSE-MsgGUID: OcwL3iSmTna8LdYBY12fqg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.19,218,1754982000"; d="scan'208";a="181349819" Received: from fmsmsx901.amr.corp.intel.com ([10.18.126.90]) by fmviesa009.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Oct 2025 00:44:10 -0700 Received: from FMSMSX903.amr.corp.intel.com (10.18.126.92) by fmsmsx901.amr.corp.intel.com (10.18.126.90) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.27; Fri, 10 Oct 2025 00:44:09 -0700 Received: from fmsedg901.ED.cps.intel.com (10.1.192.143) by FMSMSX903.amr.corp.intel.com (10.18.126.92) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.27 via Frontend Transport; Fri, 10 Oct 2025 00:44:09 -0700 Received: from CY7PR03CU001.outbound.protection.outlook.com (40.93.198.30) by edgegateway.intel.com (192.55.55.81) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.27; Fri, 10 Oct 2025 00:44:09 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=RfDTSVwiA1immjYIsGKWYIssO+aalkZjpl0eRheW+TxL2VSRMPcs48PRUBFYqg3ixcL+im7/sdUruLJN7j5DgE0MNLD4x/xSDIncKO3g7+o0iiSd2olLUZaE6q7BNH1tIzSuYLlBA5ELUIQVWTMzBjHaY6KpiG7+MPqgF8XFAHI0sGvHTOTyQghB7bNJUCk1+wTtBUp8jVkzdqFHO2OH9CxA9yhOPLFFSuBrg9NpXARBNv4uWfxx5B9OiZVzc7ZOWgKD31mOlFPh0gZoDfNJfYDUl26h/ZjEpT3DdQZBXz00ee1C5HIeu8iS6e8+wX3j4C5m0uYDTNBWepC+qeqDNA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=U9nbrr+6Ub8s6e5P/mucZ5WDXuehQzCCsgEDGn7pnR4=; b=kn9F/rr4ZKexA/6eBkuXpY9ZOHF50oBnEhaZRYMC+kFHii6uC9wNrP03f2meAcbmzWQ6yIP1be+25P7QzRTcxE4xSD1J4BrcBaDDUROjwWz1mM5igCChamcq1TSZ9vm42A1+F/BCltN4ztWxuBsVY4FckCf+zgrRlj5J0xF1PJgNkAFAPm5sCuO9HOw2/UrgAAYzhpqiIcW/ZFmv1WM5rNXWzUgK1hrDjpHnwdgNxq9JyWeNKnaMaGNmCp0nZRPt94kv75hois79D0DccCownR+Iv1p5fMEbGbGkNvpnemtUCFWfPRWCfuOs06BbjV+1vNKmDjsYYrmuJEIWcmKt+g== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=intel.com; Received: from DS0PR11MB7309.namprd11.prod.outlook.com (2603:10b6:8:13e::17) by PH7PR11MB6932.namprd11.prod.outlook.com (2603:10b6:510:207::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9203.9; Fri, 10 Oct 2025 07:44:01 +0000 Received: from DS0PR11MB7309.namprd11.prod.outlook.com ([fe80::f120:cc1f:d78d:ae9b]) by DS0PR11MB7309.namprd11.prod.outlook.com ([fe80::f120:cc1f:d78d:ae9b%4]) with mapi id 15.20.9203.007; Fri, 10 Oct 2025 07:44:01 +0000 Date: Fri, 10 Oct 2025 08:43:56 +0100 From: Bruce Richardson To: Morten =?iso-8859-1?Q?Br=F8rup?= CC: , Thomas Monjalon , Stephen Hemminger , Konstantin Ananyev , Andrew Rybchenko , Ivan Malov , Chengwen Feng Subject: Re: [PATCH v8 3/3] mbuf: optimize reset of reinitialized mbufs Message-ID: References: <20250821150250.16959-1-mb@smartsharesystems.com> <20250823063002.24326-1-mb@smartsharesystems.com> <20250823063002.24326-4-mb@smartsharesystems.com> <98CBD80474FA8B44BF855DF32C47DC35F654B7@smartserver.smartshare.dk> Content-Type: text/plain; charset="iso-8859-1" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <98CBD80474FA8B44BF855DF32C47DC35F654B7@smartserver.smartshare.dk> X-ClientProxiedBy: DUZPR01CA0275.eurprd01.prod.exchangelabs.com (2603:10a6:10:4b9::6) To DS0PR11MB7309.namprd11.prod.outlook.com (2603:10b6:8:13e::17) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS0PR11MB7309:EE_|PH7PR11MB6932:EE_ X-MS-Office365-Filtering-Correlation-Id: 720e4596-0c8a-4540-907b-08de07d0c78c X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|366016|1800799024|7053199007; X-Microsoft-Antispam-Message-Info: =?iso-8859-1?Q?7in7KeXtR/WGzF/kGzzMLfZELAKmmTjivbs2BkHZxrKG+QFsTTz8pRmFWK?= =?iso-8859-1?Q?uI6Yovav9rK67nqyrU/tRFkni3kyknDA7IXEAUuBDNQbWQEb4nn0/pPsgj?= =?iso-8859-1?Q?KZAmFapB0NpnRoQjricVESyUZvnHZ/ODYYgHNoUQfSfjC1JCv682gwA1aE?= =?iso-8859-1?Q?1DQCS+jkVjKSz1wHL2/6cBfo1ggJxhCfXoDcVWLbDYpedhEIFIgOXSBV1R?= =?iso-8859-1?Q?g/Q8DGkmYW7ahgeeHnDT8/G03v9wfL7trEiQbUbeUKR9hSHMDM2gFSg8FZ?= =?iso-8859-1?Q?ShMbGnyxkRovmi7WlgNKaaseCw7qCS4LJSCUdD1d8UxMYrkBqUKc0/5qBz?= =?iso-8859-1?Q?RS2xF1m8SPzXwh8ZJCyrAi8p3luqk7nfGUKGphzAt475tzn+Rx91h5UfEc?= =?iso-8859-1?Q?RervTUraRKDGjFnJIHoS4J3QhtJWaI5pd1lwjFTKtVXtTGtyrcYpjLwYhW?= =?iso-8859-1?Q?HaIsmUUGiNiPMMCLzkdzkp3hFDijAoLt43s9tNcurCT0jfJA8ZGTdMVm0j?= =?iso-8859-1?Q?Xg+hDyppViK4Kko49PB0OPOyEy1h4fA9eDL829e77JBlVRDHoYh96MD2td?= =?iso-8859-1?Q?Mphe7rQU+hO7oTeXauK6Y2uaAwPbgLTM7kr+UJyRqMSFih1kkD8dIRdUZc?= =?iso-8859-1?Q?gfJzT6P8p38BKmm2rn1i+Qu2F7b/Zl8g2j1HezyUOYDQ5h5VskuBaqkZeT?= =?iso-8859-1?Q?zbuSlbjS/saONTgnoYtm9aoR4RWBFBB0l5KKO5tIYjfk+oXnKjEfUfY+OJ?= =?iso-8859-1?Q?Acs72ysV+hGi6P7/zH0FqYLINRKknDBpvd+ck+MUhPqOap2arDLo6Hf+5k?= =?iso-8859-1?Q?ryrpmgkCtlsb4oL9vkksbW2aWkYNebjyKgpwWD8EOG0Lszeesu1vNB/x5n?= =?iso-8859-1?Q?vxYV95DpTSga1W7GIKtIPIjQLrtOXAfXcY21JrQgvLaG4NwsfitvlPzn+t?= =?iso-8859-1?Q?E4OcD2B8xQ7bZhDuL+BJXlPeUqzD1yjvzFMXCHX3NkKrgWhtNHr3WhROEF?= =?iso-8859-1?Q?FQMuJOHX0u1nNqY5YWxjI+reeZfWtpTPtd+ool33iJ1QZyEmd07oF562Tt?= =?iso-8859-1?Q?8pP5ELnJSiI8jjwTZ4/mx52GalcZKygPCj5egSvnj+ZMSNw+1fLCVVJY04?= =?iso-8859-1?Q?CFH/NSPft2N3IyqbQbBOrC+re2hMZipk7nva83hVCIC8v3xh0fmcgDNYO6?= =?iso-8859-1?Q?nEwmZT681Wh5uaobzE0/iPqRLUKUOcUwqjuY64+goOqFUzjbMagje/tSra?= =?iso-8859-1?Q?ov1dqlchrnvxxKrrLxjZbVvUrlFGy9EKcqZGmlnkpZ3mc5KK+BY+q9o9cn?= =?iso-8859-1?Q?e+dHdz+X5jyWwqxRj9Fv8/bwEtT42IUYRG6LGzEFGUjksRfH473jpo4lqi?= =?iso-8859-1?Q?yWBg4J20JZCvMoNWSd9XnnQpOuFkbVadv4oPICpkwoKKHSHrJ4XnbVqKWy?= =?iso-8859-1?Q?uZqCu1xIkXgu7jK+pf9PCZ56x+mswZuxvtXf2WSs1BdPySQKZzMaf43CpI?= =?iso-8859-1?Q?PrfjzMoNmaCugMMWwasv0X?= X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:DS0PR11MB7309.namprd11.prod.outlook.com; PTR:; CAT:NONE; SFS:(13230040)(376014)(366016)(1800799024)(7053199007); DIR:OUT; SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?iso-8859-1?Q?OVQZxBP++wejiWZJCKIRisU2WzGxZOHGpM+Ee11eaDpRienIwxnX5cNEHv?= =?iso-8859-1?Q?OuDIZXTcUlG59FxjMXPKgRXO5csizTZQgL6KQraKc6pNIT6m1KGmqZaUpU?= =?iso-8859-1?Q?QHba2eEXsowH3x4zllH4e9g/1SoHSIusQ+4H2ay2fRPFV/zieS8T3KWjpP?= =?iso-8859-1?Q?Q0HhCxkFTTpbktnQN5Ry7DNRWSfHo0U9oh4wxtKBIgFdwicNhxN9IraoG5?= =?iso-8859-1?Q?QIArWSFdOMyH4YI4wLv0YSIyz31RDdaweYu1IK2DAZ+9qkiSh+epBKj1Qj?= =?iso-8859-1?Q?tEWkYnZiLs4ktK3IKeisDTHYTwOXDcX4Khyeor2tO/PuHd5ujpHJbcXOIb?= =?iso-8859-1?Q?pXU5OuQoiCZhzCXDb3qrv1YuDSRE9ENHHwn+dthjAxJDSUAWDPUTRgr3RV?= =?iso-8859-1?Q?dB6tH3sPU3LHrHh5PUmS5ilu4hFOWuQHgV3eJQMf8SaIJpKJP9szp0fD9P?= =?iso-8859-1?Q?XGTvf6MnYUNERmfMs8wk4qa+Biwt6Ikif4aKEnkJHzf0yDsycTqcZLgGrW?= =?iso-8859-1?Q?Joyv78QY6nGsw7N03Pcl5P9d8yDj2dP+s4aH5RzN9D+Mo8x+vkAtYASYca?= =?iso-8859-1?Q?n+z03vl7HgOu1E+dBNlcAQi1CO7JY3TIc8QL0TMeAJbGSBWmjWnp7CJUbS?= =?iso-8859-1?Q?BYJh0rnjIISp4GReM+PqwECCJqEX4U7g7kJoMoHKKVxkGQhF2buYqpXlST?= =?iso-8859-1?Q?yTUS165ALaQ2yOwuu2bNQYrTtzNBRACnkBK9CeCRcIDiUBsMktJhYtDE3t?= =?iso-8859-1?Q?R9ek5YbYeJMfgHd9AHkmWmFCxLM5O6TMjX1j+LkzLSrhQ2vVj2IXgMY1jb?= =?iso-8859-1?Q?yTPEdMH2c4m8sYK1jjacYrV6Fr9pJ3H42umwQRjaac4h9aL5u55dSRYWqA?= =?iso-8859-1?Q?UZRDGNSkriNR0UFzLL+2h+0Zwo+rEFv1B+0bhPJ9OF8k96Kr78wzaPNrhO?= =?iso-8859-1?Q?brfUNARLVsNsce+gwyegWL3zze3mH+WHtk3Luw7FHNn2pbBeKmdUD8H/pz?= =?iso-8859-1?Q?nvpnzWQbZ94AHZ+QzTf5YqkHZqOKcQ+kbipBlmfMpY855GLl2SBoMFbjIp?= =?iso-8859-1?Q?PqM0c8d2dE1Zsd557x81Ifu2MZT0KVBwpJi4rj9yGfOOwkC1xW33qlCUV/?= =?iso-8859-1?Q?7KiBbowFYjp3tkYRSBTPaEWZ1gRsvZkM+EjjS3W0Vlq8HKKefqEPjxr6IE?= =?iso-8859-1?Q?y2m1ekOwHk5D1138PVetR+8EjD5TaLMkw4lNc8sXlyUHg0w5CSfOJFgHxZ?= =?iso-8859-1?Q?h/4oUkF4H0e1EVqOz+cfszIzU9EzwOFw9ffxCPZTpW4AwQPD9BpAhYaIHi?= =?iso-8859-1?Q?8ysLML9QLoTFZ7SvSr38vxkeg8KTfSwlQSuPe5rut4T3zlvHDjU8Co12U0?= =?iso-8859-1?Q?BvNP6lZ5HZDU49tvCotWSXuknvCM9sQMs8IlABj3bLrC1eBdCNX5EmO+Qt?= =?iso-8859-1?Q?aSHKbnLHDWeMrR1kgyBoPsnVLoisDArtF4YFEZ7vetCfPexq0+RpR6f8gj?= =?iso-8859-1?Q?YGkl8JYdzcUAC8M6aOlQnH6FmjWZXwkZK+8DHMRwvU5obOYegRxMf4HU4Q?= =?iso-8859-1?Q?iuaSlY0Z4o18gc+ZBCij2purVmIhqSXnG6OLur4IT2NMYELaY4KzDFl9B4?= =?iso-8859-1?Q?U1PvQxWe3NveV0tPi+Q79NQRSQB0U+hdGvHAHmbOqMFDo7r1hx7SXmHg?= =?iso-8859-1?Q?=3D=3D?= X-MS-Exchange-CrossTenant-Network-Message-Id: 720e4596-0c8a-4540-907b-08de07d0c78c X-MS-Exchange-CrossTenant-AuthSource: DS0PR11MB7309.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Oct 2025 07:44:01.8334 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 82NuELWMqmo4gTyZ7WpYw1d8b5D0uEZwze4gHgGInqNgkQAOP62GAz0i8PhF/F1tH3nreW+CYLsTRWtmNsC1/Bddbkj8FhwMeMYhfq6go+c= X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR11MB6932 X-OriginatorOrg: intel.com X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org On Thu, Oct 09, 2025 at 07:35:54PM +0200, Morten Brørup wrote: > > From: Bruce Richardson [mailto:bruce.richardson@intel.com] > > Sent: Thursday, 9 October 2025 19.15 > > > > On Sat, Aug 23, 2025 at 06:30:02AM +0000, Morten Brørup wrote: > > > An optimized function for resetting a bulk of newly allocated > > > reinitialized mbufs (a.k.a. raw mbufs) was added. > > > > > > Compared to the normal packet mbuf reset function, it takes advantage > > of > > > the following two details: > > > 1. The 'next' and 'nb_segs' fields are already reset, so resetting > > them > > > has been omitted. > > > 2. When resetting the mbuf, the 'ol_flags' field must indicate > > whether the > > > mbuf uses an external buffer, and the 'data_off' field must not > > exceed the > > > data room size when resetting the data offset to include the default > > > headroom. > > > Unlike the normal packet mbuf reset function, which reads the mbuf > > itself > > > to get the information required for resetting these two fields, this > > > function gets the information from the mempool. > > > > > > This makes the function write-only of the mbuf, unlike the normal > > packet > > > mbuf reset function, which is read-modify-write of the mbuf. > > > > > > Signed-off-by: Morten Brørup > > > --- > > > lib/mbuf/rte_mbuf.h | 74 ++++++++++++++++++++++++++++--------------- > > -- > > > 1 file changed, 46 insertions(+), 28 deletions(-) > > > > > > diff --git a/lib/mbuf/rte_mbuf.h b/lib/mbuf/rte_mbuf.h > > > index 49c93ab356..6f37a2e91e 100644 > > > --- a/lib/mbuf/rte_mbuf.h > > > +++ b/lib/mbuf/rte_mbuf.h > > > @@ -954,6 +954,50 @@ static inline void > > rte_pktmbuf_reset_headroom(struct rte_mbuf *m) > > > (uint16_t)m->buf_len); > > > } > > > > > > +/** > > > + * Reset the fields of a bulk of packet mbufs to their default > > values. > > > + * > > > + * The caller must ensure that the mbufs come from the specified > > mempool, > > > + * are direct and properly reinitialized (refcnt=1, next=NULL, > > nb_segs=1), > > > + * as done by rte_pktmbuf_prefree_seg(). > > > + * > > > + * This function should be used with care, when optimization is > > required. > > > + * For standard needs, prefer rte_pktmbuf_reset(). > > > + * > > > + * @param mp > > > + * The mempool to which the mbuf belongs. > > > + * @param mbufs > > > + * Array of pointers to packet mbufs. > > > + * The array must not contain NULL pointers. > > > + * @param count > > > + * Array size. > > > + */ > > > +static inline void > > > +rte_mbuf_raw_reset_bulk(struct rte_mempool *mp, struct rte_mbuf > > **mbufs, unsigned int count) > > > +{ > > > + uint64_t ol_flags = (rte_pktmbuf_priv_flags(mp) & > > RTE_PKTMBUF_POOL_F_PINNED_EXT_BUF) ? > > > + RTE_MBUF_F_EXTERNAL : 0; > > > + uint16_t data_off = RTE_MIN_T(RTE_PKTMBUF_HEADROOM, > > rte_pktmbuf_data_room_size(mp), > > > + uint16_t); > > > + > > > + for (unsigned int idx = 0; idx < count; idx++) { > > > + struct rte_mbuf *m = mbufs[idx]; > > > + > > > + m->pkt_len = 0; > > > + m->tx_offload = 0; > > > + m->vlan_tci = 0; > > > + m->vlan_tci_outer = 0; > > > + m->port = RTE_MBUF_PORT_INVALID; > > > > Have you considered doing all initialization using 64-bit stores? It's > > generally cheaper to do a single 64-bit store than e.g. set of 16-bit > > ones. > > The code is basically copy-paste from rte_pktmbuf_reset(). > I kept it the same way for readability. > I'd think using 64-bit stores should be fine for readability so long as there is a comment on each one (maybe with compile-time checks for field layout). > > This also means that we could remove the restriction on having refcnt > > and > > nb_segs already set. As in PMDs, a single store can init data_off, > > ref_cnt, > > nb_segs and port. > > Yes, I have given the concept a lot of thought already. > If we didn't require mbufs residing in the mempool to have any fields initialized, specifically "next" and "nb_segs", it would improve performance for drivers freeing mbufs back to the mempool, because writing to the mbufs would no longer be required at that point; the mbufs could simply be freed back to the mempool. Instead, we would require the driver to initialize these fields - which it probably does on RX anyway, if it supports segmented packets. > But I consider this concept a major API change, also affecting applications assuming that these fields are initialized when allocating raw mbufs from the mempool. So I haven't pursued it. > Yes, agreed. Let's not change anything in those restrictions. /Bruce