From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758273AbdEVPqK (ORCPT ); Mon, 22 May 2017 11:46:10 -0400 Received: from relay1.mentorg.com ([192.94.38.131]:59323 "EHLO relay1.mentorg.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751942AbdEVPpu (ORCPT ); Mon, 22 May 2017 11:45:50 -0400 Subject: Re: [RFC V1 1/1] net: cdc_ncm: Reduce memory use when kernel memory low To: David Miller , CC: , , , References: <1494956480-6127-1-git-send-email-jim_baxter@mentor.com> <1494956480-6127-2-git-send-email-jim_baxter@mentor.com> <87shk4fynp.fsf@miraculix.mork.no> <20170517.141819.1307166900606639947.davem@davemloft.net> From: "Baxter, Jim" Message-ID: <04bc5b49-9282-a6ca-2b95-fb8fc9750555@mentor.com> Date: Mon, 22 May 2017 16:45:42 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.1.1 MIME-Version: 1.0 In-Reply-To: <20170517.141819.1307166900606639947.davem@davemloft.net> Content-Type: text/plain; charset="utf-8" Content-Language: en-GB Content-Transfer-Encoding: 7bit X-Originating-IP: [137.202.0.87] X-ClientProxiedBy: svr-ies-mbx-01.mgc.mentorg.com (139.181.222.1) To SVR-IES-MBX-04.mgc.mentorg.com (139.181.222.4) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: David S. Miller (davem@davemloft.net) Sent: Wed, 17 May 2017 14:18:19 -0400 > > When there isn't memory pressure this will hurt performance of > course. > > It is a quite common paradigm to back down to 0 order memory requests > when higher order ones fail, so this isn't such a bad change from the > perspective. > > However, one negative about it is that when the system is under memory > stress it doesn't help at all to keep attemping high order allocations > when the system hasn't recovered yet. In fact, this can make it > worse. > Hello David, Do you think the patch should be modified to extend the length of time the 0 order memory requests with a time period of 1 minute for example? Or do you feel the patch is not the correct way this should be performed? Best regards, Jim