From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A1EEAC2D0A8 for ; Wed, 30 Sep 2020 08:23:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5C29420738 for ; Wed, 30 Sep 2020 08:23:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728169AbgI3IXX convert rfc822-to-8bit (ORCPT ); Wed, 30 Sep 2020 04:23:23 -0400 Received: from eu-smtp-delivery-151.mimecast.com ([185.58.86.151]:56120 "EHLO eu-smtp-delivery-151.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725535AbgI3IXW (ORCPT ); Wed, 30 Sep 2020 04:23:22 -0400 Received: from AcuMS.aculab.com (156.67.243.126 [156.67.243.126]) (Using TLS) by relay.mimecast.com with ESMTP id uk-mta-241-KV6fPijRMkWryXuz3TcX2Q-1; Wed, 30 Sep 2020 09:23:16 +0100 X-MC-Unique: KV6fPijRMkWryXuz3TcX2Q-1 Received: from AcuMS.Aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) by AcuMS.aculab.com (fd9f:af1c:a25b:0:43c:695e:880f:8750) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Wed, 30 Sep 2020 09:23:15 +0100 Received: from AcuMS.Aculab.com ([fe80::43c:695e:880f:8750]) by AcuMS.aculab.com ([fe80::43c:695e:880f:8750%12]) with mapi id 15.00.1347.000; Wed, 30 Sep 2020 09:23:15 +0100 From: David Laight To: 'Jakub Kicinski' , Wei Wang CC: Eric Dumazet , "David S . Miller" , netdev , Paolo Abeni , Hannes Frederic Sowa , "Felix Fietkau" Subject: RE: [RFC PATCH net-next 0/6] implement kthread based napi poll Thread-Topic: [RFC PATCH net-next 0/6] implement kthread based napi poll Thread-Index: AQHWlqpf5e4ajsfgAEyc0khQ0bcmAamA19lw Date: Wed, 30 Sep 2020 08:23:15 +0000 Message-ID: <4600c4617b4b41fa8522ab2d0c8ea822@AcuMS.aculab.com> References: <20200914172453.1833883-1-weiwan@google.com> <20200929121902.7ee1c700@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <20200929144847.05f3dcf7@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> In-Reply-To: <20200929144847.05f3dcf7@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> Accept-Language: en-GB, en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Jakub Kicinski > Sent: 29 September 2020 22:49 ... > Isn't the fundamental problem that scheduler works at ms scale while > where we're talking about 100us at most? And AFAICT scheduler doesn't > have a knob to adjust migration cost per process? :( Have you tried setting the application processes to RT priorities? The scheduler tries very hard (maybe too hard) to avoid migrating RT processes. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)