From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.lichtvoll.de (lichtvoll.de [37.120.160.25]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C4FA911CBA for ; Sun, 14 Sep 2025 12:06:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=37.120.160.25 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757851623; cv=none; b=JwrFG9m3tjaQzVPY8VpfsCZt9t9WqxwXi5z+EE45SDnrdx9wyy9+sZdV1bOYfIw4yKp3B64VbmeeUsTrRcJ3PxjxAL8Au8TBQBasHp0RF3VAUUkHMv5P+QIR8Yg6b0d2S2PetFkBkLIUWcQqEbZwRDZKLsjfJChojRy15J7WX3s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757851623; c=relaxed/simple; bh=qwGcpIc3rcGD5Soyf5Lf0JVXhCnC6vZ1yBvvzmMp3kc=; h=From:To:Subject:Date:Message-ID:MIME-Version:Content-Type; b=AbxyFtzS8PCrPiPNVKaRi0hnG4g6rFMwdcDdpoM/8rIjqsgvaiq39WkWw6OZYKYUBukZGOVmZpvgrqLHOBkTgrQySl1k6NPO8/rZS7mjxIVjXGLERqwwHnSfIUdSEPX5Qw+ZMqp1RCJ3cWl/cm7BWiM0CblvQ843nVedstToY6A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=lichtvoll.de; spf=pass smtp.mailfrom=lichtvoll.de; arc=none smtp.client-ip=37.120.160.25 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=lichtvoll.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lichtvoll.de Received: from 127.0.0.1 (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature ECDSA (secp384r1) server-digest SHA384) (No client certificate requested) by mail.lichtvoll.de (Postfix) with ESMTPSA id B197414410D for ; Sun, 14 Sep 2025 11:57:55 +0000 (UTC) Authentication-Results: mail.lichtvoll.de; auth=pass smtp.auth=martin@lichtvoll.de smtp.mailfrom=martin@lichtvoll.de From: Martin Steigerwald To: BTRFS Subject: SSD overheating during scrub in laptop Date: Sun, 14 Sep 2025 13:57:52 +0200 Message-ID: <1938311.tdWV9SEqCh@lichtvoll.de> Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Hi! Just to share an experience and ask whether others have experienced this. Already during summer it happened, that the Samsung 990 Pro 4 TB SSD in=20 this ThinkPad T14 AMD Gen 5 said goodbye during scrubbing a 2 TB BTRFS=20 filesystem with almost 2 TB of data in big files running at about 3,5 to=20 4,2 GiB/s. I concluded this being due to excessive heat. However it still succeeded with the 500 GiB /home with about 300-350 GiB=20 of data in it back then. I worked around it, by scrubbing two minutes,=20 then canceling, waiting to cool down, resuming for two minutes until the=20 7-9 minutes of scrubbing were complete. I tried to work around with=20 lowered speed, but even then the temperature slowly rose till the SSD said= =20 goodbye. I think I went down to 1 GiB/s of speed maximum, maybe even below= =20 that. But then the scrubbing takes longer so more time for SSD to heat up.= =20 However=E2=80=A6 I would have thought it would not heat that much with a sl= ower=20 speed. Maybe it would have worked with 50 or 100 MiB/s. But this takes=20 long. Now I had these SSD goodbyes during regular use in times of heavy I/O and=20 in the end it could not even scrub that /home partition anymore in one go.= =20 Linux hung and only way to recover was to forcefully power off the laptop. I opened the laptop and removed dust with high pressure air can while=20 holding the fan still so it would not generate current. And with disabled=20 laptop battery. This fixed the SSDs goodbye issue and I could even scrub that 2 TiB=20 filesystem again. However, according to sensors command it still had about= =20 80,8 =C2=B0C composite temperature and even 100,8 =C2=B0C for sensor 2 for = the NVME=20 SSD at "nvme-pci-0300" shortly before the end of the scrub, with critical=20 for composite at 84,8 =C2=B0C, but no critical set for sensor 2. That is st= ill=20 quite high. Granted, it took about 7-8 minutes of scrubbing at 3,5 to 4,2=20 GiB/s in one go for it to heat up like this. But on the other hand it is=20 not summer anymore and room is not as hot as in summer. Anyone had similar experiences? My solution to this will be to remove the dust inside laptop about every=20 half year. However=E2=80=A6 I was a bit surprised that the NVME SSD would n= ot=20 throttle itself before saying goodbye. Or maybe it tried and it was not=20 enough or to late? The laptop is a bit less than 15 months old. So I=20 conclude that it takes less than a year for the cooling system to become=20 quite a bit less effective due to dust. Good old ThinkPad T520 took way=20 longer for that. But it is way larger on the other hand with more space to= =20 distribute heat. I bet it is out of scope for btrfs scrub command to monitor NVME SSD=20 temperature and pause when to high. And I conclude the NVME layer of the=20 kernel is not throttling to hot NVME flash either. I checked my data filesystems, two BTRFS and one BCacheFS by scrubbing and= =20 fsck'ing without changing anything. They are okay. Best, =2D-=20 Martin