From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=95.215.58.143 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1792463577; b=DwrsodW46qc9mQ9G+Fin25GFmi2zI92K8qYi6H65Ie3+p7HtLUzIgOAh86Q+3xI/4iat SCPRh2ZwrDpVk9m5u1Ehw7KicgqmO2u3OYsrt4oxFbrXdD0F8U1g1J0aJkD+C79pKshwH itJavgkWohG0n01ifZ7Ag7RNJYrAJTC7nLiIL9n+w+KIj+F1miDq7w6zgzxBwImWhta6y /4O2ihaHalOhOMKYsvllXkrI2u/7JA1NeCEdbsfNPwuKYc4o07/sXLrVBgKKwgutp/0cE 5X9a1oba/Hl1ph3D+XYwjCWX4ZavkBivTJm+dQ6HE+D3NRdmc0X7uEIJ3R+LuqykDZg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1792463577; h=DMARC-Filter:X-Envelope-To:DKIM-Signature:X-Envelope-To:Received: X-Mizu-Trace-ID:X-Migadu-Flow:Content-Type:Mime-Version:Subject:From: In-Reply-To:Date:Cc:Content-Transfer-Encoding:Message-Id:References: To:X-Mailer; bh=+UeasOj6C0QSBv81NOjtXL/pSwcDJf+q6grtY75QD48=; b=l4mwtgjg5JWVuitxf01vH5ua0pOvBPsW/oMXj8r4ilPi64lqyJZa3BYvmC7FfUoT5sLo Va2JoVFDHeWjN1Ut5SH1Zh7Qzk3htR6xqp/s2/uj2gzUI/HMdPKm83qxUjrOhOBMOBo6z dYFlbvG0ZpN4nUB/JGQ194jALAcZhgx5PgZsJxD0Qi1HVg+iKm+EugrcHVJlMVjCRex4L uK2w2JE137Xtumf32WR5deBTqIUfV57JCB7YoAHQLfYLjQi/3n/KmHILx/5+egurRpULc WRX/NFXg7eGgw3DSoVwB65YUm19QdNof6AKHZShIMLPPuhCNOBE0LInkqlzZ0DbdsLA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=jgBMRNhe; arc=none smtp.remote-ip=95.215.58.143 Received: from mta1.migadu.com (out-143.mta1.migadu.com [95.215.58.143]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature ECDSA (prime256v1) server-digest SHA256) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 919A3606A31A for ; Tue, 20 Oct 2026 02:32:56 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org 919A3606A31A Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linux.dev header.i=@linux.dev header.a=rsa-sha256 header.s=key1 header.b=jgBMRNhe X-Envelope-To: cgroups@vger.kernel.org DKIM-Signature: a=rsa-sha256; bh=+UeasOj6C0QSBv81NOjtXL/pSwcDJf+q6grtY75QD48=; c=simple/simple; d=linux.dev; h=from:to:subject:date:message-id:mime-version:content-type; s=key1; t=1792463574; v=1; x=1793068374; b=jgBMRNheZKBI5mN5E7/ygI01+OFOk9dLk3mfNcNlhr/2K5tksjaBe9b9XywguOAT6nYV4j4e Hcs16QQgHVkYMkPGmmhMJ65IXPtKIiA4Cw20stlqJD9ct3HzAYPYQXW+d1SCWPWkTUwBpi/9RhL C4av6/ba0qR4JfXR/j1x/jrw= X-Envelope-To: cgroups@vger.kernel.org Received: by mta11.migadu.com with ESMTPS id 8af93f4628e3430e; Tue, 20 Oct 2026 02:32:54 +0000 X-Mizu-Trace-ID: 8af93f4628e3430e X-Migadu-Flow: FLOW_OUT Content-Type: text/plain; charset=us-ascii X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3901.100.1.1.12\)) Subject: Re: [PATCH v3] mm/shrinker: allocate shrinker_info_unit from a dedicated kmem_cache From: Muchun Song In-Reply-To: <20261019-vstor-144715-shrinker_info_unit-kmem_cache-v3-1-0fb061e09bf4@virtuozzo.com> Date: Tue, 20 Oct 2026 10:32:34 +0800 Cc: Andrew Morton , Dave Chinner , Qi Zheng , Roman Gushchin , Johannes Weiner , Michal Hocko , Shakeel Butt , linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org Content-Transfer-Encoding: quoted-printable Message-Id: <285B262E-95AF-4BBD-923C-922DDDF0E70C@linux.dev> References: <20261019-vstor-144715-shrinker_info_unit-kmem_cache-v3-1-0fb061e09bf4@virtuozzo.com> To: Konstantin Khorenko X-Mailer: Apple Mail (2.3901.100.1.1.12) > On Oct 20, 2026, at 00:11, Konstantin Khorenko = wrote: >=20 > shrinker_info_unit holds BITS_PER_LONG atomic_long_t of deferred work > plus a one-word bitmap, 520 bytes on 64-bit. kzalloc_node() takes it > from kmalloc-1k, so almost half of every unit is padding. >=20 > Allocate the units from a cache of their own, sized to the unit. The > cache is not cache-line aligned: the counters of a unit already share > cache lines between shrinkers, and aligning the unit would only keep > neighbouring units off each other's boundary line, at the cost of part > of the saving. >=20 > Suggested-by: Andrew Morton > Assisted-by: LLM > Signed-off-by: Konstantin Khorenko Acked-by: Muchun Song Thanks.