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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 865C7C4332F for ; Wed, 16 Nov 2022 23:53:58 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 0F3966B0072; Wed, 16 Nov 2022 18:53:58 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 0A45A6B0073; Wed, 16 Nov 2022 18:53:58 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id ED4956B0074; Wed, 16 Nov 2022 18:53:57 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id DF9DD6B0072 for ; Wed, 16 Nov 2022 18:53:57 -0500 (EST) Received: from smtpin09.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id AF35A801C3 for ; Wed, 16 Nov 2022 23:53:57 +0000 (UTC) X-FDA: 80140960914.09.755C43D Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf25.hostedemail.com (Postfix) with ESMTP id 73758A000B for ; Wed, 16 Nov 2022 23:53:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Sender:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=jXsTQ6UgBt/n03y8z/yQU/gmTXj684z17e8Hwln5Ysc=; b=Phd0VpGqvG8wUAIlVn6fL650de QC1iMSQcjGMBgvA1CS/TNEhuGge33jnn9B7xA8sUnlDsQhFIt3ubkwmJflsTMPG4Qu4Wvm1VW2f5L 5iNVrqrzkhtvYyHDsKsNxR1YmXgdC2boX1zPw13BAqiZsgaTiaNtQN9HsmVQYApH5WwKRjbDVx7UO a50PfDO5KWfO2PmI9r525caVcBYwPvRnH0NIKY4GdHH14XOt8Yz1A7tPI+q9h5OD8X6HnLPJO2b+w 1YOD0uL+RcAQokioVBV8dj8OF3I6mESmV0hvVKBynnCyQMNeDJ6gkXiOcVJiNTIBCy9wqQOW2ydCd tYYe4c8A==; Received: from mcgrof by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1ovSE0-008lxa-Md; Wed, 16 Nov 2022 23:53:48 +0000 Date: Wed, 16 Nov 2022 15:53:48 -0800 From: Luis Chamberlain To: "Edgecombe, Rick P" Cc: "song@kernel.org" , "peterz@infradead.org" , "bpf@vger.kernel.org" , "rppt@kernel.org" , "linux-mm@kvack.org" , "hch@lst.de" , "x86@kernel.org" , "akpm@linux-foundation.org" , "Lu, Aaron" Subject: Re: [PATCH bpf-next v2 0/5] execmem_alloc for BPF programs Message-ID: References: <20221107223921.3451913-1-song@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1668642837; a=rsa-sha256; cv=none; b=WWEdaVAYtMOWiEqF5em2lclQg7hl5I3Rq1qKJvKs+m7/L3JAhTywPQjtav7zdQVmec7bvX lkVKDtKFPYVOiuRDZkXHGWAZRk2fZY7q7wG7/77AFFPEITw8KHwaaxG7w9fvRlqBSAkZbA 60PlBBU/i5fGBcDOhpfQuJnGrZlYLS8= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=Phd0VpGq; dmarc=fail reason="No valid SPF, DKIM not aligned (relaxed)" header.from=kernel.org (policy=none); spf=none (imf25.hostedemail.com: domain of mcgrof@infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=mcgrof@infradead.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1668642837; h=from:from:sender:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=jXsTQ6UgBt/n03y8z/yQU/gmTXj684z17e8Hwln5Ysc=; b=cXluQdzNyetEk9sSCVkqihpzPFAwSlnpzClgAtgQt1sXE8ZzuZ0cTVZaoYkTplBEgz5lG3 IpmP2Wx3YqpjLOFSdG+KhDD3NDxK66xFzhZzCeoEzl/dcRYpMrAGZmwkBHgSXTIdTbngL/ vO0W4jyml8XRyN8tgSt+ARUWx1CokDM= X-Rspamd-Queue-Id: 73758A000B Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b=Phd0VpGq; dmarc=fail reason="No valid SPF, DKIM not aligned (relaxed)" header.from=kernel.org (policy=none); spf=none (imf25.hostedemail.com: domain of mcgrof@infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=mcgrof@infradead.org X-Rspam-User: X-Rspamd-Server: rspam05 X-Stat-Signature: drrkaxsbxpswpediihftr1ddaqntgrh3 X-HE-Tag: 1668642836-331700 X-Bogosity: Ham, tests=bogofilter, spamicity=0.012173, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Nov 16, 2022 at 10:47:04PM +0000, Edgecombe, Rick P wrote: > On Wed, 2022-11-16 at 14:33 -0800, Luis Chamberlain wrote: > > More in lines with what I was hoping for. Can something just do > > the parallelization for you in one shot? Can bench alone do it for > > you? > > Is there no interest to have soemthing which generically showcases > > multithreading / hammering a system with tons of eBPF JITs? It may > > prove useful. > > > > And also, it begs the question, what if you had another iTLB generic > > benchmark or genearl memory pressure workload running *as* you run > > the > > above? I as, as it was my understanding that one of the issues was > > the > > long term slowdown caused by the directmap fragmentation without > > bpf_prog_pack, and so such an application should crawl to its knees > > over time, and there should be numbers you could show to prove that > > too, before and after. > > We did have some benchmarks that showed if your direct map was totally > fragmented (started from boot at 4k page size) what the regression was: > > > https://lore.kernel.org/linux-mm/213b4567-46ce-f116-9cdf-bbd0c884eb3c@linux.intel.com/ Oh yes that is a good example of effort, but I'm suggesting taking for instance will-it-scale and run it in tandem with bpg prog pack and measure on *both* iTLB differences, before / after, *and* doing this again after a period of expected deterioation of the direct map fragmentation (say after non-bpf-prog-pack shows high direct map fragmetnation). This is the sort of thing which easily go into a commit log. Luis