From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-171.mta1.migadu.com (out-171.mta1.migadu.com [95.215.58.171]) (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 09974239E9D for ; Mon, 2 Feb 2026 04:55:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=95.215.58.171 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770008112; cv=none; b=qaU66v9nsVEUocvY3lB1oHVp6zl99VTIivsskE0D7PewWrY7/JUgDIXNaB2FSyuujPit5uKWqtTgzsrE3zbWhRYGxbcjsa3cd9c9IfwGR0+fOJRTeRhlsu5iwR4OpUAu6VvFFZho88KLWEl3YjfKO+Q2FjsbwbmpjPnGel3cqLc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1770008112; c=relaxed/simple; bh=TmlArQDdr1ZAc/NGzLSsuGnx+WpytNv+fOdrcGsTK8o=; h=MIME-Version:Date:Content-Type:From:Message-ID:Subject:To:Cc: In-Reply-To:References; b=I95b+SpaU/SHJ04JXtugQrVEcAGnDahotFQuY3WdHcN34klWFR6mRuec1zAdarbqQZjfEQLS9q8DV71MuwTDlZIDWfufqE3u/JP7gPLIsD0dEreJjw9dlu/+QnH5KDGjlMN3TWaaWCuzEAP+wFEhpH0wyG9fDDnm/Tvp64vg4uo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=K7xHFaVH; arc=none smtp.client-ip=95.215.58.171 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) header.d=linux.dev header.i=@linux.dev header.b="K7xHFaVH" Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1770008099; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=iQMGuhj4v1Wf/hZq+ihAsexgXJVjJdPHN5MjuTUGtm4=; b=K7xHFaVH9oPc1Yh/xCOEHjVjZmuhacqZUTn0fta11OA0WnR0Dr+LIqDT7D0B84IMh2J6Gw T3unqGruLGEy02l4zvf1P4muxuoHYLbqQR9gEqrO6tXdtQ2j6CPXKIiRg6/EmZcUIB8x5F k/F2dWJsb0YCvxzTEmk8H8uxDGq5He4= Date: Mon, 02 Feb 2026 04:54:56 +0000 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: "Shakeel Butt" Message-ID: <51819ca5a15d8928caac720426cd1ce82e89b429@linux.dev> TLS-Required: No Subject: Re: [PATCH 1/4] memcg: use mod_node_page_state to update stats To: "Dev Jain" Cc: "Andrew Morton" , "Johannes Weiner" , "Michal Hocko" , "Roman Gushchin" , "Muchun Song" , "Harry Yoo" , "Qi Zheng" , "Vlastimil Babka" , linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, "Meta kernel team" In-Reply-To: <2638bd96-d8cc-4733-a4ce-efdf8f223183@arm.com> References: <20251110232008.1352063-1-shakeel.butt@linux.dev> <20251110232008.1352063-2-shakeel.butt@linux.dev> <1052a452-9ba3-4da7-be47-7d27d27b3d1d@arm.com> <2638bd96-d8cc-4733-a4ce-efdf8f223183@arm.com> X-Migadu-Flow: FLOW_OUT > >=20 >=20> >=20 >=20> > Hello Shakeel, > > >=20 >=20> > We are seeing a regression in micromm/munmap benchmark with this= patch, on arm64 - > > > the benchmark mmmaps a lot of memory, memsets it, and measures the= time taken > > > to munmap. Please see below if my understanding of this patch is c= orrect. > > >=20 >=20> Thanks for the report. Are you seeing regression in just the bench= mark > > or some real workload as well? Also how much regression are you seei= ng? > > I have a kernel rebot regression report [1] for this patch as well w= hich > > says 2.6% regression and thus it was on the back-burner for now. I w= ill > > take look at this again soon. > >=20 >=20The munmap regression is ~24%. Haven't observed a regression in any o= ther > benchmark yet. Please share the code/benchmark which shows such regression, also if you = can share the perf profile, that would be awesome.