From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41342) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1elGRK-0000aO-P0 for qemu-devel@nongnu.org; Mon, 12 Feb 2018 10:54:47 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1elGRI-0007qP-2U for qemu-devel@nongnu.org; Mon, 12 Feb 2018 10:54:46 -0500 From: Alberto Garcia In-Reply-To: <1518441241-32557-2-git-send-email-anton.nefedov@virtuozzo.com> References: <1518441241-32557-1-git-send-email-anton.nefedov@virtuozzo.com> <1518441241-32557-2-git-send-email-anton.nefedov@virtuozzo.com> Date: Mon, 12 Feb 2018 16:54:39 +0100 Message-ID: MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Qemu-devel] [PATCH v2 1/2] iotest 033: add misaligned write-zeroes test via truncate List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anton Nefedov , qemu-devel@nongnu.org Cc: qemu-block@nongnu.org, kwolf@redhat.com, mreitz@redhat.com, stefanha@redhat.com, famz@redhat.com, eblake@redhat.com On Mon 12 Feb 2018 02:14:00 PM CET, Anton Nefedov wrote: > +# Trigger truncate that would shrink qcow2 L1 table, which is done by > +# clearing one entry (8 bytes) with bdrv_co_pwrite_zeroes() > + > +echo > +echo "=== Test misaligned write zeroes via truncate ===" > +echo > + > +CLUSTER_SIZE=$((64 * 1024)) > +L2_COVERAGE=$(($CLUSTER_SIZE * $CLUSTER_SIZE / 8)) > +_make_test_img $(($L2_COVERAGE * 2)) If my numbers are correct, that's a 1GB image. For qcow2 this is not a problem but I wonder if it's ok to create such large images for other formats (for raw they should be sparse by default, but still). Berto