Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754188AbbHMVHv (ORCPT ); Thu, 13 Aug 2015 17:07:51 -0400 Received: from mx0a-00082601.pphosted.com ([67.231.145.42]:23321 "EHLO mx0a-00082601.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754118AbbHMVHt (ORCPT ); Thu, 13 Aug 2015 17:07:49 -0400 Date: Thu, 13 Aug 2015 14:07:04 -0700 From: Calvin Owens To: Eric Dumazet CC: Sorin Dumitru , Sorin Dumitru , David Miller , , , , , netdev , , Subject: Re: [PATCH] net: Use SK_MEM_QUANTUM as minimum for tcp/udp rmem/wmem Message-ID: <20150813210704.GA3055575@mail.thefacebook.com> References: <1438806414-751067-1-git-send-email-calvinowens@fb.com> <20150809.224114.818332231954008575.davem@davemloft.net> <20150811033406.GA1136819@mail.thefacebook.com> <20150810.204630.1903301700926701432.davem@davemloft.net> <20150812045420.GA3908557@mail.thefacebook.com> <1439389261.29802.3.camel@edumazet-glaptop2.roam.corp.google.com> <1439401585.29802.15.camel@edumazet-glaptop2.roam.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Disposition: inline In-Reply-To: <1439401585.29802.15.camel@edumazet-glaptop2.roam.corp.google.com> User-Agent: Mutt/1.5.20 (2009-12-10) X-Originating-IP: [192.168.52.123] X-Proofpoint-Spam-Reason: safe X-FB-Internal: Safe X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.14.151,1.0.33,0.0.0000 definitions=2015-08-13_10:2015-08-13,2015-08-13,1970-01-01 signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1172 Lines: 29 On Wednesday 08/12 at 10:46 -0700, Eric Dumazet wrote: > On Wed, 2015-08-12 at 20:00 +0300, Sorin Dumitru wrote: > > > Would clamping the values to a min value, like setsockopt(SO_SNDBUF) > > does, be an option? > > I still find it odd that SO_SNDBUF limits you, while the /proc > > interface doesn't. If you think it's > > too much, I'm ok with reverting it since it affects scripts. > > > > On those arches where PAGE_SIZE == 64K(or > 16K) it looks like we have > > tcp_wmem[1] > > smaller than tcp_wmem[0]. Shouldn't we do something about this? > > As long as we do not crash if/when root user changes /proc/sys/net > settings, we are good. Using "1 1 1" for tcp_{r,w}mem seems not to explode, so this sounds good to me. I'll send a new patch reverting the original. Thanks, Calvin > I would not care if performance is bad if root does something really > stupid. root user is supposed to not mess things just for fun. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/