From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Collins Subject: fq_codel and skb->hash Date: Mon, 16 Jan 2017 17:04:44 -0700 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 7bit Cc: To: Return-path: Received: from mail-sn1nam01on0138.outbound.protection.outlook.com ([104.47.32.138]:61511 "EHLO NAM01-SN1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751012AbdAQAEw (ORCPT ); Mon, 16 Jan 2017 19:04:52 -0500 Sender: netdev-owner@vger.kernel.org List-ID: The fq_codel packet scheduler always regenerates the skb flow hash. Is there any reason to do this other than the recent hash perturbation additions? I ask because I have a case where an incoming set of TCP flows is encapsulated in a single ipsec tunnel, which is then classified on egress into a single flow by fq_codel resulting in poor behavior. Reusing the skb hash set in receive results in much better behavior, as the value is determined pre-encapsulation and flows end up being distributed more naturally across codel queues. Is opportunistically using the pre-existing skb hash (if available) problematic? Is there a better way to manage flow separation in routed+encapsulated traffic? Thanks, Andrew Collins