From patchwork Mon Sep 1 15:35:49 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Joao Marcos Costa X-Patchwork-Id: 69347 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 aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 331DCCA0FF0 for ; Mon, 1 Sep 2025 15:36:21 +0000 (UTC) Received: from smtpout-04.galae.net (smtpout-04.galae.net [185.171.202.116]) by mx.groups.io with SMTP id smtpd.web11.54884.1756740970104701823 for ; Mon, 01 Sep 2025 08:36:11 -0700 Authentication-Results: mx.groups.io; dkim=fail reason="dkim: body hash did not verify" header.i=@bootlin.com header.s=dkim header.b=Ck7uifu4; spf=pass (domain: bootlin.com, ip: 185.171.202.116, mailfrom: joaomarcos.costa@bootlin.com) Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-04.galae.net (Postfix) with ESMTPS id 43D06C8F1E0 for ; Mon, 1 Sep 2025 15:35:53 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 22D5B60699; Mon, 1 Sep 2025 15:36:08 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id F1B8A1C22D935; Mon, 1 Sep 2025 17:36:06 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1756740967; h=from:subject:date:message-id:to:cc:mime-version: content-transfer-encoding; bh=OQrFgewgoDbS0XaUaOSNfVxxzv/OWJUZbMcR/LdwwrM=; b=Ck7uifu41InI0kIW40giV1G0C+jBCbWNFcs5z11KWhMw8W4RjHMfAiz4KubVwhsmxvnWbj XobyNhIKfHw7deNkn0YWQc7TkAp0SyqqY7UG4cN29yy6tC78pjQr5n3sCGZvHLRTqKpr+a qb73aHK/UIsK9uFEnm8TI0TVdK2hx0Tpdrj7MWTrq0QO3hMgFdahAcOMUoCUZ4V6/lCJAE rLBmuqBp7SY8PSIudgQwFHXasyYbHJHV0YSBBwMUOm1r6WM7mHEAdnkVd/b2dddyrQFDHu XetzsJXF8KvyaZ6V6n1gmwhhszgKb/uw0XVV9TKG8M99MiJPhweSke1emrZwig== From: joaomarcos.costa@bootlin.com To: docs@lists.yoctoproject.org Cc: thomas.petazzoni@bootlin.com, quentin.schulz@cherry.de, Joao Marcos Costa Subject: [docs][PATCH v2] ref-manual/variables.rst: expand IMAGE_OVERHEAD_FACTOR glossary entry Date: Mon, 1 Sep 2025 17:35:49 +0200 Message-ID: <20250901153549.552589-1-joaomarcos.costa@bootlin.com> X-Mailer: git-send-email 2.47.0 MIME-Version: 1.0 X-Last-TLS-Session-Version: TLSv1.3 List-Id: X-Webhook-Received: from li982-79.members.linode.com [45.33.32.79] by aws-us-west-2-korg-lkml-1.web.codeaurora.org with HTTPS for ; Mon, 01 Sep 2025 15:36:21 -0000 X-Groupsio-URL: https://lists.yoctoproject.org/g/docs/message/7476 From: Joao Marcos Costa There's a (second) overhead factor applied in images generated with Wic, and this is already documented in the .wks reference. However, the IMAGE_OVERHEAD_FACTOR entry does not mention it, and by looking at the partition sizes (e.g. with parted) one may find it confusing that they don't match with the expected rootfs size (e.g. in a scenario where the extra space is "0" and IMAGE_OVERHEAD_FACTOR="1.0"). This second overhead is already documented, though: https://docs.yoctoproject.org/ref-manual/kickstart.html#command-part-or-partition Mention the '--overhead-factor' option in the glossary entry and add a reference to the wks documentation. Signed-off-by: Joao Marcos Costa Reviewed-by: Quentin Schulz --- documentation/ref-manual/variables.rst | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/documentation/ref-manual/variables.rst b/documentation/ref-manual/variables.rst index d559899c6..b7fd1cc5e 100644 --- a/documentation/ref-manual/variables.rst +++ b/documentation/ref-manual/variables.rst @@ -4166,6 +4166,11 @@ system and gives an overview of their function and contents. added to the image by using the :term:`IMAGE_ROOTFS_EXTRA_SPACE` variable. + When using Wic tool, beware that a second overhead factor is also applied. + This overhead value is defined by the ``--overhead-factor`` option, which + defaults to "1.3" when omitted. See the ":doc:`/ref-manual/kickstart`" + (Command: part or partition) chapter for details. + :term:`IMAGE_PKGTYPE` Defines the package type (i.e. DEB, RPM or IPK) used by the OpenEmbedded build system. The variable is defined appropriately by