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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 214B4C4332F for ; Mon, 13 Nov 2023 06:55:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232011AbjKMGzC (ORCPT ); Mon, 13 Nov 2023 01:55:02 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38806 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229645AbjKMGzB (ORCPT ); Mon, 13 Nov 2023 01:55:01 -0500 Received: from truschnigg.info (truschnigg.info [89.163.150.210]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E473010E6 for ; Sun, 12 Nov 2023 22:54:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=truschnigg.info; s=m22; t=1699858496; bh=+UsXkWyeooSPEnDs4mfW0PI5uLx1bkI3pMR5IBiidVQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=sBvXf9BFcRYHtwh03jWFWfYRImKtciqd/ASjvZ7wkfpnbcfxFXFUIQsiNzZ1oLCfT 5chQB6QU76BDgvcW3gVhStLoK2TqbzW4fS5ZYuECOpkU384/HwRvLZhPZrU72DCwyX D4+yHIwDMiI525PAOP9/UYhdlh/ZrcbskLV1rGuaO+4S17brlDGlzaL9bNIwX54e+Y U2moflvuKtIsvxV0BckG1NyTiG/nobys12rnvqiUtctg282vHNTBDKGqLxj14wWprV 3y4xYciTxAERuEesf9idZuAwSM/D7BQHe3b+8MV0oXBUr33G6NJ361s+wMBSegCub9 pJcodmBRH9ytQ== Received: from vault.lan (unknown [IPv6:2a02:1748:fafe:cf3f:1eb7:2cff:fe02:8261]) by truschnigg.info (Postfix) with ESMTPSA id C47272037E; Mon, 13 Nov 2023 06:54:55 +0000 (UTC) Date: Mon, 13 Nov 2023 07:54:52 +0100 From: Johannes Truschnigg To: eyal@eyal.emu.id.au Cc: linux-raid@vger.kernel.org Subject: Re: extremely slow writes to array [now not degraded] Message-ID: References: <1d0fb40a-1908-4b5e-9856-a5b79eafdc9c@eyal.emu.id.au> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="9FdvQO99FBlCSsWE" Content-Disposition: inline In-Reply-To: <1d0fb40a-1908-4b5e-9856-a5b79eafdc9c@eyal.emu.id.au> Precedence: bulk List-ID: X-Mailing-List: linux-raid@vger.kernel.org --9FdvQO99FBlCSsWE Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable You will need to generate some kind of call stack/graph info to start making sense of the mess your running kernel gets itself into in the scenario you described. I imagine that looking at `perf` (`perf top` in particular; it should suffi= ce to paste a few instances of its topmost lines when the involved kernel thre= ads are spinning) would yield some useful data to kick off a potentially productive debate about what could actually be going on. On Fedora, I think `sudo dnf install perf` should set up everything you need to get you going; then, look at `sudo perf top -F 999` for a while, and let the list know what you see. (You can use your terminal emulator's flow cont= rol features, available via Ctrl+S to enable and Ctrl+Q to disable, to "freeze" the output to make it easier to copy it into a clipboard buffer.) --=20 with best regards: - Johannes Truschnigg ( johannes@truschnigg.info ) www: https://johannes.truschnigg.info/ phone: +436502133337 xmpp: johannes@truschnigg.info --9FdvQO99FBlCSsWE Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAEBCgAdFiEEGu9IhkI+7/aKLUWF95W3jMsYfLUFAmVRyDkACgkQ95W3jMsY fLUPGw/+MXtzahCqXAyXx2Xn60VBRpWjXeiT3MM5f0glsZ+HC3vVe1K4sNguH9Hi hIwh73xovMj9lklXH4vgzShUGama0hqhuDrSVm7to/e8t/5RCAVTUWzvNekO8yNe I49vUs/0huqMPm6EwXuS06pBDxHEHcHhuE8LUNqtW0mci7e4D/x2Wkn2VKcxnWZy LS9Q7vr0c1mGPo/ji097gijmCxoo9aTexXDZqE+16fHKDNVsvpfPGw/dvXmC+0UL n+du6V9HFKHtcn5uANuIMBadLM8o5G8xgyTEglrVo4UgX2O5HAWyF4b6EB3zjIs7 q+RF9ZVAopBiNmKKE3513ED1nzBSfvhmJH9Cb0RaJF56+6Nrcw5XyaXic1ubNI9v kswmS3RHICHqoQ0ngwbDm6I6n2ZWk0bVFGZhDtFN24td8KEM3er8DW2OvDIv1QCl OVYGUFIs6fLLmdy9eCGQ+czYgepCPLbjaBbyDRb49CEY8i/gJgi+Q+E7kjzTt4NL un2d+aFqcgt4tGr+V+fvxWWG1OTHD2ZoRDL2ZnoOOw5VzlMfTrzgb4RVs6kudohH /AQYKUs1oWHJoEIlThGOrfm5Ihc1Os3WLd1trQhL7Me8nJrWzvhXrn4qnC7QnBed mapnK4erPA4bRFGPIhj42v05rJTc7obWzsgJ6XZNPY+6HVnLI8A= =bGOb -----END PGP SIGNATURE----- --9FdvQO99FBlCSsWE--