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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id CF4F8C433EF for ; Sat, 12 Feb 2022 08:35:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232684AbiBLIfS (ORCPT ); Sat, 12 Feb 2022 03:35:18 -0500 Received: from mxb-00190b01.gslb.pphosted.com ([23.128.96.19]:40142 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232647AbiBLIfR (ORCPT ); Sat, 12 Feb 2022 03:35:17 -0500 Received: from alexa-out.qualcomm.com (alexa-out.qualcomm.com [129.46.98.28]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D9E56213; Sat, 12 Feb 2022 00:35:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1644654914; x=1676190914; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=MeLi2dYMbbNIf6RjIa19QVwgVecV8z/lw2J8bW0VgqA=; b=B8Qk5IvWIuVLPOMKuZ01+xFnjeAMJt9tzKBvDotGGYt4wrKxwG/secK8 sBLipi7oMMQWTrUEztyFHCrHdgMj2gU6ZdzmLE4iuJKtdF/tAYZ5wRmho UJwMfWxra6WLRwDWB8VILyGz0ePmDobTT+xXcNIIB93DlXDNIJ5a4r7cx w=; Received: from ironmsg09-lv.qualcomm.com ([10.47.202.153]) by alexa-out.qualcomm.com with ESMTP; 12 Feb 2022 00:35:14 -0800 X-QCInternal: smtphost Received: from nasanex01c.na.qualcomm.com ([10.47.97.222]) by ironmsg09-lv.qualcomm.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Feb 2022 00:35:13 -0800 Received: from nalasex01a.na.qualcomm.com (10.47.209.196) by nasanex01c.na.qualcomm.com (10.47.97.222) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.15; Sat, 12 Feb 2022 00:35:13 -0800 Received: from [10.38.246.233] (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.922.19; Sat, 12 Feb 2022 00:35:10 -0800 Message-ID: <2add9ba7-7bc8-bd1d-1963-61e8154b0e3c@quicinc.com> Date: Sat, 12 Feb 2022 00:35:08 -0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.5.1 Subject: Re: [PATCH] devcoredump: increase the device delete timeout to 10 mins Content-Language: en-US To: Johannes Berg , Greg KH CC: , , , , , , , , , , , , References: <1644349472-31077-1-git-send-email-quic_abhinavk@quicinc.com> <654d620b-9e14-c47f-b48c-762dc0bd32a1@quicinc.com> <7db7d01fcf5a3edce61161769c0e6eb1541237bf.camel@sipsolutions.net> From: Abhinav Kumar In-Reply-To: <7db7d01fcf5a3edce61161769c0e6eb1541237bf.camel@sipsolutions.net> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nalasex01a.na.qualcomm.com (10.47.209.196) Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Hi Johannes On 2/12/2022 12:24 AM, Johannes Berg wrote: > On Fri, 2022-02-11 at 23:52 -0800, Abhinav Kumar wrote: >> >> The thread is writing the data to a file in local storage. From our >> profiling, the read is the one taking the time not the write. >> > > That seems kind of hard to believe, let's say it's a 4/3 split (4 > minutes reading, 3 minutes writing, to make read > write as you say), > and 3MiB size, that'd mean you get 12.8KiB/sec? That seems implausibly > low, unless you're reading with really tiny buffers? > > Can you strace this somehow? (with timestamp info) > Yes, like I have already mentioned in earlier comments, we continue to check whats taking that long. Once we find something from our analysis and also have the trace, will update the thread. >> Just doubling what we have currently. I am not sure how the current 5 >> mins timeout came from. >> > > To be honest it came out of thin air, and wasn't really meant as a limit > on how fast you can read (feels like even if it's tens of MiB you should > read it in milliseconds into userspace), but more of a maximum time that > we're willing to waste kernel memory if nobody is around to read the > data. > > I thought it'd be better if we could somehow pin it while the userspace > is reading it, but OTOH maybe that's actually bad, since that means > userspace (though suitably privileged) could pin this kernel memory > indefinitely. > > johannes 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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A0382C433F5 for ; Sat, 12 Feb 2022 08:35:17 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id E43D610E76A; Sat, 12 Feb 2022 08:35:16 +0000 (UTC) Received: from alexa-out.qualcomm.com (alexa-out.qualcomm.com [129.46.98.28]) by gabe.freedesktop.org (Postfix) with ESMTPS id E297010E3AF; Sat, 12 Feb 2022 08:35:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1644654915; x=1676190915; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=MeLi2dYMbbNIf6RjIa19QVwgVecV8z/lw2J8bW0VgqA=; b=LxEGvLV4OBRPKoSXVubmg5DLunfB1XQzXJpq0Mfre+Mmzo35gWt8QXKs qklwdd58mal9El9N6DsEMZpmW7NSPtnmdctVqLzBRqrARQjs3tKqLdOzd y1sXIqtZE2Rk5RmZzvQmQudUrldHR8FbNpoEKy0LvF59w7takWUvvUN9o s=; Received: from ironmsg09-lv.qualcomm.com ([10.47.202.153]) by alexa-out.qualcomm.com with ESMTP; 12 Feb 2022 00:35:14 -0800 X-QCInternal: smtphost Received: from nasanex01c.na.qualcomm.com ([10.47.97.222]) by ironmsg09-lv.qualcomm.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Feb 2022 00:35:13 -0800 Received: from nalasex01a.na.qualcomm.com (10.47.209.196) by nasanex01c.na.qualcomm.com (10.47.97.222) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.15; Sat, 12 Feb 2022 00:35:13 -0800 Received: from [10.38.246.233] (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.922.19; Sat, 12 Feb 2022 00:35:10 -0800 Message-ID: <2add9ba7-7bc8-bd1d-1963-61e8154b0e3c@quicinc.com> Date: Sat, 12 Feb 2022 00:35:08 -0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.5.1 Subject: Re: [PATCH] devcoredump: increase the device delete timeout to 10 mins Content-Language: en-US To: Johannes Berg , Greg KH References: <1644349472-31077-1-git-send-email-quic_abhinavk@quicinc.com> <654d620b-9e14-c47f-b48c-762dc0bd32a1@quicinc.com> <7db7d01fcf5a3edce61161769c0e6eb1541237bf.camel@sipsolutions.net> From: Abhinav Kumar In-Reply-To: <7db7d01fcf5a3edce61161769c0e6eb1541237bf.camel@sipsolutions.net> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01b.na.qualcomm.com (10.46.141.250) To nalasex01a.na.qualcomm.com (10.47.209.196) X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: rafael@kernel.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, swboyd@chromium.org, khsieh@codeaurora.org, nganji@codeaurora.org, seanpaul@chromium.org, dmitry.baryshkov@linaro.org, aravindh@codeaurora.org, freedreno@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi Johannes On 2/12/2022 12:24 AM, Johannes Berg wrote: > On Fri, 2022-02-11 at 23:52 -0800, Abhinav Kumar wrote: >> >> The thread is writing the data to a file in local storage. From our >> profiling, the read is the one taking the time not the write. >> > > That seems kind of hard to believe, let's say it's a 4/3 split (4 > minutes reading, 3 minutes writing, to make read > write as you say), > and 3MiB size, that'd mean you get 12.8KiB/sec? That seems implausibly > low, unless you're reading with really tiny buffers? > > Can you strace this somehow? (with timestamp info) > Yes, like I have already mentioned in earlier comments, we continue to check whats taking that long. Once we find something from our analysis and also have the trace, will update the thread. >> Just doubling what we have currently. I am not sure how the current 5 >> mins timeout came from. >> > > To be honest it came out of thin air, and wasn't really meant as a limit > on how fast you can read (feels like even if it's tens of MiB you should > read it in milliseconds into userspace), but more of a maximum time that > we're willing to waste kernel memory if nobody is around to read the > data. > > I thought it'd be better if we could somehow pin it while the userspace > is reading it, but OTOH maybe that's actually bad, since that means > userspace (though suitably privileged) could pin this kernel memory > indefinitely. > > johannes