From nobody Mon Feb 9 02:51:10 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) by mx.zohomail.com with SMTPS id 1500994507935623.9883503952475; Tue, 25 Jul 2017 07:55:07 -0700 (PDT) Received: from localhost ([::1]:33007 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1da1En-0004VZ-IK for importer@patchew.org; Tue, 25 Jul 2017 10:55:05 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36626) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1da12F-000221-2n for qemu-devel@nongnu.org; Tue, 25 Jul 2017 10:42:08 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1da12D-00011x-5s for qemu-devel@nongnu.org; Tue, 25 Jul 2017 10:42:07 -0400 Received: from mx-v6.kamp.de ([2a02:248:0:51::16]:52305 helo=mx01.kamp.de) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1da12C-00010s-Sz for qemu-devel@nongnu.org; Tue, 25 Jul 2017 10:42:05 -0400 Received: (qmail 15793 invoked by uid 89); 25 Jul 2017 14:42:03 -0000 Received: from [195.62.97.28] by client-16-kamp (envelope-from , uid 89) with qmail-scanner-2010/03/19-MF (clamdscan: 0.99.2/23595. avast: 1.2.2/17010300. spamassassin: 3.4.1. 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Processed in 0.272009 secs); 25 Jul 2017 14:42:03 -0000 Received: from smtp.kamp.de (HELO submission.kamp.de) ([195.62.97.28]) by mx01.kamp.de with ESMTPS (DHE-RSA-AES256-GCM-SHA384 encrypted); 25 Jul 2017 14:42:00 -0000 Received: (qmail 9633 invoked from network); 25 Jul 2017 14:41:40 -0000 Received: from lieven-pc.kamp-intra.net (HELO lieven-pc) (relay@kamp.de@::ffff:172.21.12.60) by submission.kamp.de with ESMTPS (DHE-RSA-AES256-GCM-SHA384 encrypted) ESMTPA; 25 Jul 2017 14:41:40 -0000 Received: by lieven-pc (Postfix, from userid 1000) id 53D2920ECB; Tue, 25 Jul 2017 16:41:40 +0200 (CEST) X-GL_Whitelist: yes From: Peter Lieven To: qemu-block@nongnu.org Date: Tue, 25 Jul 2017 16:41:33 +0200 Message-Id: <1500993699-19299-5-git-send-email-pl@kamp.de> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1500993699-19299-1-git-send-email-pl@kamp.de> References: <1500993699-19299-1-git-send-email-pl@kamp.de> X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 2a02:248:0:51::16 Subject: [Qemu-devel] [PATCH V5 04/10] qemu-img: add documentation for compress settings X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: kwolf@redhat.com, Peter Lieven , qemu-devel@nongnu.org, mreitz@redhat.com, den@openvz.org, lersek@redhat.com Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail: RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Signed-off-by: Peter Lieven --- qemu-img.texi | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/qemu-img.texi b/qemu-img.texi index 72dabd6..3612c59 100644 --- a/qemu-img.texi +++ b/qemu-img.texi @@ -676,6 +676,32 @@ file which is COW and has data blocks already, it coul= dn't be changed to NOCOW by setting @code{nocow=3Don}. One can issue @code{lsattr filename} to chec= k if the NOCOW flag is set or not (Capital 'C' is NOCOW flag). =20 +@item compress.format +Defines which compression algorithm is should be used for compressed clust= ers. +The following options are available if support for the respective libraries +has been enabled at compile time: + + deflate Uses standard zlib defalte compression + +The compression algorithm can only be defined at image create time and can= not +be changed later. + +Note: defining compression format settings which are different from the old + default (format=3Ddeflate, level=3D0, window-size=3D12) will result = in the + compression format extension being written to the Qcow2 image. Versi= ons + of QEMU before 2.11 will not be able to open images with this extens= ion. + +@item compress.level +Valid for compress.format=3Ddeflate defines the compression level to use f= or +selected compression format. The default of @code{compress.level=3D0} will= use +the default compression level for the format. Alternate values range from = 1 for +fastest compression to 9 for the best compression. + +@item compress.window-size +Valid for compress.format=3Ddeflate defines the compression window size us= ed +during compression. Valid window sizes for deflate compression range from = 8 to +15 inclusively. The default is @code{compress.window-size=3D15}. + @end table =20 @item Other --=20 1.9.1