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=-4.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 201B5C432BE for ; Sun, 29 Aug 2021 14:58:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E040460F3A for ; Sun, 29 Aug 2021 14:58:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235465AbhH2O7l (ORCPT ); Sun, 29 Aug 2021 10:59:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:33126 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235452AbhH2O7k (ORCPT ); Sun, 29 Aug 2021 10:59:40 -0400 Received: by mail.kernel.org (Postfix) with ESMTPS id 7C11160F46 for ; Sun, 29 Aug 2021 14:58:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1630249128; bh=S+Pu1dTjQIflgJn7se2MGLz5unqa+Zxsn07NEukFikE=; h=From:To:Subject:Date:In-Reply-To:References:From; b=uXyL1phebIMA0UMinXPqcvMsIzoosGgF2kSpthvNN246zd8F2HCcQss+udEC+B8xQ qh1WBQ7IOeMDJ1fseqMoV4/0jcn/sZx7PZZslpx+/QPmPJblJ2qYeCHHBx2/A4/Tis WCJKpN6XfHL5JWrfa51dZr7Fr9wUJ4l5AW4us66LjO91BpmqgQ3eT/pKG47TC3Xf9c K6JXzjktx4bpeSbjXcxHaGLcr8kI4Y+hYZtW5j6ZlsAf+/5JLWxUZlohZagpsPwnko n+W6pKSIKuIvPkauL+p0Wm7b3MwQAtDRZ49m0P5BoHr3hjDrQJowXm7TIxyfyuaguI qHta4gHWGGdCg== From: bugzilla-daemon@bugzilla.kernel.org To: kvm@vger.kernel.org Subject: [Bug 199727] CPU freezes in KVM guests during high IO load on host Date: Sun, 29 Aug 2021 14:58:47 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: AssignedTo virtualization_kvm@kernel-bugs.osdl.org X-Bugzilla-Product: Virtualization X-Bugzilla-Component: kvm X-Bugzilla-Version: unspecified X-Bugzilla-Keywords: X-Bugzilla-Severity: high X-Bugzilla-Who: devzero@web.de X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P1 X-Bugzilla-Assigned-To: virtualization_kvm@kernel-bugs.osdl.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org https://bugzilla.kernel.org/show_bug.cgi?id=3D199727 --- Comment #5 from Roland Kletzing (devzero@web.de) --- apparently, things got even worse with proxmox 7, as it seems it's using as= ync io (via io_uring) by default for all virtual disk IO, i.e. the workaround "cache=3Dwriteback" does not work for me anymore. if i set aio=3Dthreads by directly editing VM configuration, things run smo= othly again. so, still being curious: why do VMs get severe hiccup with async (via io_submit or io_uring) when storage is getting some load and why does that NOT happen with the described workaround ? --=20 You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.=