From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [63.128.21.124]) by mx.groups.io with SMTP id smtpd.web10.334.1610737428897739953 for ; Fri, 15 Jan 2021 11:03:49 -0800 Authentication-Results: mx.groups.io; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=TPZwcciG; spf=pass (domain: redhat.com, ip: 63.128.21.124, mailfrom: lersek@redhat.com) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1610737428; 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: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3oZsyZC9FYXJlVZ23MLKpm8XM6eU8UlCkdW4ZJ4KQ2o=; b=TPZwcciGS7gitUQ+gAAWy0lyTYqmW/Td5YNrnaAjvoNK5nwGG52bTcU77p+cMwcLVfSB0O 82DyJ2/755uzry/x0BxHWplVW3SPK0xe5+0eXOLDIfN21uQyQO0vMAnxVxP4aDkoplTOwL 9LFioPuXea81O2QehQYDtSwqMEGe83s= 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-412-SR9O_GMZMG2-IBYvs4N88Q-1; Fri, 15 Jan 2021 14:03:44 -0500 X-MC-Unique: SR9O_GMZMG2-IBYvs4N88Q-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id A5D521015C92; Fri, 15 Jan 2021 19:03:42 +0000 (UTC) Received: from lacos-laptop-7.usersys.redhat.com (ovpn-112-152.ams2.redhat.com [10.36.112.152]) by smtp.corp.redhat.com (Postfix) with ESMTP id E75A7722C8; Fri, 15 Jan 2021 19:03:38 +0000 (UTC) Subject: Re: [edk2-devel] [PATCH v2 03/10] ArmVirtPkg: raise PcdShellFileOperationSize to 128KB To: devel@edk2.groups.io, philmd@redhat.com Cc: Ard Biesheuvel , Leif Lindholm References: <20210113085453.10168-1-lersek@redhat.com> <20210113085453.10168-4-lersek@redhat.com> From: "Laszlo Ersek" Message-ID: <83fe625a-b5ba-1986-eeb8-8b594f654f5b@redhat.com> Date: Fri, 15 Jan 2021 20:03:37 +0100 MIME-Version: 1.0 In-Reply-To: X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=lersek@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit On 01/15/21 16:59, Philippe Mathieu-Daudé wrote: > On 1/13/21 9:54 AM, Laszlo Ersek wrote: >> Some UEFI shell commands read and write files in chunks. The chunk size is >> given by "PcdShellFileOperationSize", whose default in >> "ShellPkg/ShellPkg.dec" is 4KB (0x1000). >> >> The virtio-fs daemon of QEMU advertizes a 128KB maximum buffer size by >> default, for the FUSE_WRITE operation. >> >> By raising PcdShellFileOperationSize 32-fold, the number of FUSE write >> requests shrinks proportionately, when writing large files. And when a >> Virtio Filesystem is not used, a 128KB chunk size is still not >> particularly wasteful. >> >> Cc: Ard Biesheuvel >> Cc: Leif Lindholm >> Cc: Philippe Mathieu-Daudé >> Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=3125 >> Signed-off-by: Laszlo Ersek >> Acked-by: Ard Biesheuvel >> --- >> >> Notes: >> v2: >> - no changes >> - pick up Ard's A-b >> >> ArmVirtPkg/ArmVirtQemu.dsc | 1 + >> ArmVirtPkg/ArmVirtQemuKernel.dsc | 1 + >> 2 files changed, 2 insertions(+) > > (Similar comment that OVMF patch, QEMU should advertise properly the > maximum buffer size). It does! :) > Reviewed-by: Philippe Mathieu-Daude Thanks! Laszlo > > > > > >