From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 56E5640DFA1; Sat, 14 Mar 2026 22:06:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773526010; cv=none; b=gL+qsximTkaFn71AHzlkB+wK1/gx8+pF+7PETWLN7vO9/iLO0U2oHJ5bNDsm8UBtz3XPPwyWwUNyEFfqguPqmvdGmxnFht1cETTWBoXR6/3myEx1tJIXFcbJlC9pS/4SJ2SlXi4Thyr8MGwAdve1XaP3SzCyz9xJVVarRYNlM8k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1773526010; c=relaxed/simple; bh=qFxp43Mm4v3Jwrh3SFQJoMvzIOQudIZXdLxg7F2u1so=; h=Date:From:To:Cc:Subject:Message-Id:In-Reply-To:References: Mime-Version:Content-Type; b=JE7Qocllrwr1BYcSKQ78nMjPu7jgCa4xhQvlUdZNTMCahE83Q3dpoQb8SO60YTLqeG7Yw2SRimTosoTI4HLPhTZ98GBxbfJQgRiNL+huFhGOMUMrJYtGSGQJBnhpH8s320Gpv9P9Xd6tXqDtqoGoZ4f6qDJxe7TqhtLw9TG2as4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b=l4gL+N6n; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux-foundation.org header.i=@linux-foundation.org header.b="l4gL+N6n" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 89D9BC116C6; Sat, 14 Mar 2026 22:06:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1773526009; bh=qFxp43Mm4v3Jwrh3SFQJoMvzIOQudIZXdLxg7F2u1so=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=l4gL+N6nnqHyaoEQiL7IxfxGqTBigZvjoFyxvfgdugUwNmpsFDLp+eExHsH8GXC1w qMUYGKxbg7K1B6cNlBk3VnyceL/pat1Cw3zhR+Hqp1zPP13eoRcSgEafdKqZZoWn+w FfK32JPY+HB6NU+yDwYaEhnsBO3tWRP1ViV4FLlQ= Date: Sat, 14 Mar 2026 15:06:49 -0700 From: Andrew Morton To: Benjamin Block Cc: Thomas Gleixner , linux-kernel , linux-s390 , Qian Cai Subject: Re: [PATCH] debugobjects: Allow to configure the amount of pre-allocated objects Message-Id: <20260314150649.9a7c4bf4554b1288eb471edc@linux-foundation.org> In-Reply-To: <20260313142620.GG2161595@p1gen4-pw042f0m> References: <70f06193b3c3581802710ebcef74671e50c4c979.1772035270.git.bblock@linux.ibm.com> <20260311100431.GC46248@p1gen4-pw042f0m.fritz.box> <20260311104727.8f7b1492141b6d61fc1b2791@linux-foundation.org> <20260313142620.GG2161595@p1gen4-pw042f0m> X-Mailer: Sylpheed 3.8.0beta1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Fri, 13 Mar 2026 15:26:20 +0100 Benjamin Block wrote: > > obj_static_pool[] is __initdata, so the consequences of making it large > > are very slight. So do we really need > > CONFIG_DEBUG_OBJECTS_POOL_SIZE_SHIFT? Requiring a rebuild is a huge > > hassle. How about simply making the static pool much larger and leave > > it at that? > > I was thinking about that but then couldn't decide what would be "big enough" > as constant value for "everyone". My test systems wasn't even that "big", and > I'm already at 1280 KiB reservation to make ODEBUG "survive" the boot. Not > sure I want to make this say 2 MiB without config option for everyone. 2MB of initmem probably just doesn't matter. Annoying. Do you understand *why* s390 is using so many objects? Presumably the current much smaller default is OK for most systems - my googling for "Out of memory. ODEBUG disabled" turned up very little. Oh, look what I found. https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1807440.html What happened to that?