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 7469AC433EF for ; Wed, 23 Mar 2022 21:32:32 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 841B06B0072; Wed, 23 Mar 2022 17:32:31 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 7F2666B0073; Wed, 23 Mar 2022 17:32:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6BA596B0074; Wed, 23 Mar 2022 17:32:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0004.hostedemail.com [216.40.44.4]) by kanga.kvack.org (Postfix) with ESMTP id 5AA5D6B0072 for ; Wed, 23 Mar 2022 17:32:31 -0400 (EDT) Received: from smtpin24.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 12701A5A79 for ; Wed, 23 Mar 2022 21:32:31 +0000 (UTC) X-FDA: 79276950102.24.4B4D9CE Received: from casper.infradead.org (casper.infradead.org [90.155.50.34]) by imf23.hostedemail.com (Postfix) with ESMTP id 3043A14002C for ; Wed, 23 Mar 2022 21:32:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=mYNJfGGSVaocDlmcw7Y6SzRfFy2YudcedELxKPfKos4=; b=AALIGi39gaeafdIUdimblw8VAP GcF2M2hi3z/FkOGSIrNoAIvW4v4ViL+ZEGcUkHD7Sw5lTir86cvGWJOBSouooJ7I/ABC2xgHVZqAh PYKRde2/ygfGxXHxCa1SJTX8On5h7jhfp5BPDbu3fSE0Aczm1ro+lWQZxn2gS6N1ufFTG6+31ZDir iwDqMGs5JBl+ZgMEV14T7SfD4XE9g2O7cn68Rb/r2nScpALp5TloWG5sbOm2xm8o3LjFPeJurqgvO fQU35onhWq+GAp0Xxz1V8aeurBAsJbffkof+iCNluYLS0klgtGkojzu0aLcYido3SBV8HD5ieMr26 5G3hdpMg==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1nX8aU-00CrO3-AE; Wed, 23 Mar 2022 21:32:14 +0000 Date: Wed, 23 Mar 2022 21:32:14 +0000 From: Matthew Wilcox To: Thiago Becker Cc: linux-nfs@vger.kernel.org, steved@redhat.com, trond.myklebust@hammerspace.com, anna.schumaker@netapp.com, kolga@netapp.com, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: Re: [PATCH RFC v3 0/6] Intruduce nfsrahead Message-ID: References: <20220323201841.4166549-1-tbecker@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220323201841.4166549-1-tbecker@redhat.com> X-Stat-Signature: yux8wdf1nmogaq8czqfn53rq3y1abg5s Authentication-Results: imf23.hostedemail.com; dkim=pass header.d=infradead.org header.s=casper.20170209 header.b=AALIGi39; spf=none (imf23.hostedemail.com: domain of willy@infradead.org has no SPF policy when checking 90.155.50.34) smtp.mailfrom=willy@infradead.org; dmarc=none X-Rspam-User: X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 3043A14002C X-HE-Tag: 1648071150-619158 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Mar 23, 2022 at 05:18:35PM -0300, Thiago Becker wrote: > Recent changes in the linux kernel caused NFS readahead to default to > 128 from the previous default of 15 * rsize. This causes performance > penalties to some read-heavy workloads, which can be fixed by > tuning the readahead for that given mount. Which recent changes? Something in NFS or something in the VFS/MM? Did you even think about asking a wider audience than the NFS mailing list? I only happened to notice this while I was looking for something else, otherwise I would never have seen it. The responses from other people to your patches were right; you're trying to do this all wrong. Let's start out with a bug report instead of a solution. What changed and when?