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 X-Spam-Level: X-Spam-Status: No, score=-6.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5B86C432BE for ; Fri, 6 Aug 2021 13:45:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CB4406113C for ; Fri, 6 Aug 2021 13:45:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344412AbhHFNpX (ORCPT ); Fri, 6 Aug 2021 09:45:23 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:23217 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344423AbhHFNpW (ORCPT ); Fri, 6 Aug 2021 09:45:22 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1628257506; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=0VbV96j7hcbKHoJWYg0a5r9V2HBRp69cIOXkwt8uqKA=; b=ZoQOOf7rMyKP/cfJtsWzYpFTtKDfxIAimd/MsQ0lkosBnjKYftPPrPARb5IDczSHiaNPeo VrHQ7umDk75RdKRxojOHjjfOdPEl9EW7Z+btRGbXtLmhs7ohUWZtk9D8P3+IF0Tg/Mmnpb cnTi7TSyOis7qpS5nTfo6VYhCzaDzHc= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-208-o9kCuQ05PaaOrCW-qhce1A-1; Fri, 06 Aug 2021 09:45:03 -0400 X-MC-Unique: o9kCuQ05PaaOrCW-qhce1A-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id BA11296DCFF; Fri, 6 Aug 2021 13:45:00 +0000 (UTC) Received: from warthog.procyon.org.uk (unknown [10.22.32.7]) by smtp.corp.redhat.com (Postfix) with ESMTP id E6BD75D9D5; Fri, 6 Aug 2021 13:44:49 +0000 (UTC) Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: References: <1017390.1628158757@warthog.procyon.org.uk> <1170464.1628168823@warthog.procyon.org.uk> <1186271.1628174281@warthog.procyon.org.uk> <1219713.1628181333@warthog.procyon.org.uk> To: Matthew Wilcox Cc: dhowells@redhat.com, Anna Schumaker , Trond Myklebust , Jeff Layton , Steve French , Dominique Martinet , Mike Marshall , Miklos Szeredi , Shyam Prasad N , Linus Torvalds , linux-cachefs@redhat.com, linux-afs@lists.infradead.org, linux-nfs@vger.kernel.org, linux-cifs@vger.kernel.org, ceph-devel@vger.kernel.org, v9fs-developer@lists.sourceforge.net, devel@lists.orangefs.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: Canvassing for network filesystem write size vs page size MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <1302764.1628257488.1@warthog.procyon.org.uk> Date: Fri, 06 Aug 2021 14:44:48 +0100 Message-ID: <1302765.1628257488@warthog.procyon.org.uk> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Precedence: bulk List-ID: X-Mailing-List: linux-cifs@vger.kernel.org Matthew Wilcox wrote: > Filesystems should not make an assumption about this ... I suspect > the optimum page size scales with I/O bandwidth; taking PCI bandwidth > as a reasonable proxy, it's doubled five times in twenty years. There are a lot more factors than you make out. Local caching, content crypto, transport crypto, cost of setting up RPC calls, compounding calls to multiple servers. David