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Grimes" CC: Cy Schubert , Yuri Pankov , freebsd-current Subject: Re: NFSv3 issues with latest -current Thread-Topic: NFSv3 issues with latest -current Thread-Index: AQHTUMopas8UmakPy0GlL/yJGiaU1aL952ZqgABGtoCAAH96LA== Date: Wed, 1 Nov 2017 00:27:50 +0000 Message-ID: References: , <201710311646.v9VGknFO082029@pdx.rh.CN85.dnsmgr.net> In-Reply-To: <201710311646.v9VGknFO082029@pdx.rh.CN85.dnsmgr.net> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1; YTOPR0101MB2171; 6:pP2G7MZqv02C+NtBESXoUOV6NniqB1qZRrtVS4lXqakjOyFfjdODx6dSC0TBUx62OsfvEWl1tvaGy1wVtGhIjuLkrReZGMNbmFa+pT+EGhlzOFMNCiZHNQjlN0IgIWm/9A5oJd70gqgNYvsdk9HjUrfpEgNh2DyIvmS2LK0Zu0ahh9vAINib4sjznZSd7bW7j+mScoe8pd17CpJO9TkWCvmPDG4hfzNDVTgQmjl7EpdKECJrrjK4yPtVvp5ZlhDux95l+gACkhaZ5wz9CixcceU8SxccbEUXrjRobWn+LTV/f709loPocS7xGVqg8/BQlIH2Ok00rEJpzCVTZJND6QQt8OhNXxGq7hm+4ocTmA8=; 5:b8gx4VDqGR+inkqWbBvNKvj6e6kOqT5V+5z1tNByXoVCgl+kbUAx2L17KovNu2MBjNN5Wjt9DWYZmeRxp+xjzqbNR8HLo/5odlI/g33VPScm+IFdvI4MSx3zaegmy4h2aPRKqOY9cG1ixWCoIbDBB4LUlCmGUdSTxxgDL/j+k0Q=; 24:PldEfyVKSTFrYt9vUFCGSOIkbaIeZeumhGTHNjfh9CMX+DHGfOYtWAl4Xnxndlu+Rqy1W0zIODuMfZMs1rCoTI66CgfCi/0yQnylYGdfnRE=; 7:cCxwZZVT9ylwkHcDjW2PHRN41c5DrIpiSpNsOmmVxdlzxxpQIkODxudcMInh+ybSW75Gs+TC0Bsi9BzNlBnRIcacxhAG1qE18KrRfsf+sLMa4zMlxXh8oWx3dxHa1hNCT+lT+7QSgFNVjiQgKrTMz/1dk2MmQl4bHSSZ5Q2hxfacxiKEZDpwklUPQ3AMZcVI+Zm8LYDKcquH4J7FgK1GcECCa7jrSuJXQ8uDr6VYOY7LF3AI0hbFSReGErE1dy9b x-ms-exchange-antispam-srfa-diagnostics: SSOS; x-ms-office365-filtering-correlation-id: 9536ea62-0f9a-4bb1-5be1-08d520bf62c0 x-microsoft-antispam: UriScan:; BCL:0; PCL:0; RULEID:(22001)(4534020)(4602075)(2017052603238); SRVR:YTOPR0101MB2171; x-ms-traffictypediagnostic: YTOPR0101MB2171: x-exchange-antispam-report-test: UriScan:; x-microsoft-antispam-prvs: x-exchange-antispam-report-cfa-test: BCL:0; PCL:0; RULEID:(100000700101)(100105000095)(100000701101)(100105300095)(100000702101)(100105100095)(6040450)(2401047)(5005006)(8121501046)(10201501046)(3002001)(100000703101)(100105400095)(3231020)(93006095)(93001095)(6041248)(20161123558100)(201703131423075)(201702281529075)(201702281528075)(201703061421075)(201703061406153)(20161123555025)(20161123564025)(20161123562025)(20161123560025)(6072148)(201708071742011)(100000704101)(100105200095)(100000705101)(100105500095); SRVR:YTOPR0101MB2171; BCL:0; PCL:0; RULEID:(100000800101)(100110000095)(100000801101)(100110300095)(100000802101)(100110100095)(100000803101)(100110400095)(100000804101)(100110200095)(100000805101)(100110500095); SRVR:YTOPR0101MB2171; x-forefront-prvs: 0478C23FE0 x-forefront-antispam-report: SFV:NSPM; SFS:(10009020)(6009001)(376002)(346002)(76094002)(189002)(199003)(24454002)(33656002)(54356999)(105586002)(50986999)(76176999)(74482002)(478600001)(229853002)(2900100001)(106356001)(6436002)(25786009)(6506006)(786003)(68736007)(101416001)(54906003)(316002)(189998001)(3280700002)(81156014)(3660700001)(8936002)(53936002)(2950100002)(6246003)(4326008)(2906002)(8676002)(81166006)(55016002)(102836003)(97736004)(5250100002)(14454004)(6916009)(74316002)(305945005)(9686003)(7696004)(86362001)(8666007)(5660300001); DIR:OUT; SFP:1101; SCL:1; SRVR:YTOPR0101MB2171; H:YTOPR0101MB2172.CANPRD01.PROD.OUTLOOK.COM; FPR:; SPF:None; PTR:InfoNoRecords; MX:1; A:1; LANG:en; received-spf: None (protection.outlook.com: uoguelph.ca does not designate permitted sender hosts) authentication-results: spf=none (sender IP is ) smtp.mailfrom=rmacklem@uoguelph.ca; spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: uoguelph.ca X-MS-Exchange-CrossTenant-Network-Message-Id: 9536ea62-0f9a-4bb1-5be1-08d520bf62c0 X-MS-Exchange-CrossTenant-originalarrivaltime: 01 Nov 2017 00:27:50.9471 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: be62a12b-2cad-49a1-a5fa-85f4f3156a7d X-MS-Exchange-Transport-CrossTenantHeadersStamped: YTOPR0101MB2171 X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Nov 2017 00:27:53 -0000 Rodney W. Grimes wrote: [stuff snipped] > I wrote: >> Btw, NFS often causes this because... >> - Typically TSO is limited to a 64K packet (including TCP/IP and MAC hea= ders). >> - When NFS does reading/writing, it will do 64K + NFS, TCP/IP and MAC he= aders >> for an RPC (or a multiple of 64K like 128K). >> --> This results in tcp_output() generating a 64K TSO segment followed b= y a >> small TCP segment (since another RPC message doesn;t usually end up >> queued quickly enough to fill in the rest of the second TCP segment= ). >> - Also, at the end of file, you can get an RPC which is just under 64K i= ncluding >> NFS and TCP/IP headers. (The drivers often broke when adding the MAC >> header bumped this case to > 64K.) >> >> Thanks go to Yuri for diagnosing this, rick > > Just a thought, not asking anyone to write one :-) > > It would be handy to have some sh(1) scripts that can exercise this bug > case and have it readily avaliable to network driver authors for testing > the tso (or other large segment) code. You can't easily reproduce this from userland. It depends on the way NFS fi= lls in the mbuf chain for I/O RPCs. (iSCSI does something similar.) However, if your shell script does an NFS mount and the writes/reads a file just under 64K in size on the mount... rick=