From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754285Ab0JBDEO (ORCPT ); Fri, 1 Oct 2010 23:04:14 -0400 Received: from out01.mta.xmission.com ([166.70.13.231]:45142 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753002Ab0JBDEN (ORCPT ); Fri, 1 Oct 2010 23:04:13 -0400 From: ebiederm@xmission.com (Eric W. Biederman) To: Davide Libenzi Cc: Robin Holt , Pekka Enberg , linux-kernel@vger.kernel.org References: <20101001200143.GR14064@sgi.com> Date: Fri, 01 Oct 2010 20:04:06 -0700 In-Reply-To: (Davide Libenzi's message of "Fri, 1 Oct 2010 13:37:08 -0700 (PDT)") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-XM-SPF: eid=;;;mid=;;;hst=in02.mta.xmission.com;;;ip=98.207.157.188;;;frm=ebiederm@xmission.com;;;spf=neutral X-SA-Exim-Connect-IP: 98.207.157.188 X-SA-Exim-Mail-From: ebiederm@xmission.com X-Spam-Report: * -1.0 ALL_TRUSTED Passed through trusted hosts only via SMTP * 0.0 T_TM2_M_HEADER_IN_MSG BODY: T_TM2_M_HEADER_IN_MSG * -3.0 BAYES_00 BODY: Bayes spam probability is 0 to 1% * [score: 0.0000] * -0.0 DCC_CHECK_NEGATIVE Not listed in DCC * [sa03 1397; Body=1 Fuz1=1 Fuz2=1] * 0.4 UNTRUSTED_Relay Comes from a non-trusted relay X-Spam-DCC: XMission; sa03 1397; Body=1 Fuz1=1 Fuz2=1 X-Spam-Combo: ;Davide Libenzi X-Spam-Relay-Country: Subject: Re: max_user_watches overflows on 16TB system. X-Spam-Flag: No X-SA-Exim-Version: 4.2.1 (built Fri, 06 Aug 2010 16:31:04 -0600) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Davide Libenzi writes: > On Fri, 1 Oct 2010, Robin Holt wrote: > >> >> Following a boot of a 16TB system, we noticed that the max_user_watches >> sysctl was negative. Is there any downside to converting that to a >> static long and handling the fallout from the change? I believe that >> fallout includes changing the definition of epoll_watches over to an >> atomic_long_t as well. >> >> Alternatively should we just limit max_user_watches to INT_MAX? > > 2B watches looks an acceptable limit to me, at least for now. > Nobody complained about not having enough of them so far. Which suggests that we need to force the boot time calculation to not exceed 2B. >>From the sysctl interface perspective now that all of it is exported as ascii strings I don't see a problem there. Eric