From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from outgoing.mit.edu (outgoing-auth-1.mit.edu [18.9.28.11]) (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 87D67266576 for ; Fri, 27 Feb 2026 01:12:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=18.9.28.11 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772154756; cv=none; b=pi/jkcLbXnE488h4MxHBoSQVmMUMVKRuh7YXhi6MlQMlwvg/ynxR1Bzp+UF2v8ywqVz7Zim/v+jiIC3xASyufCMrSve7pY/FE/8tqekAMBpNwrMXDuxTXP1CI4ROZV0CT9X6URBe2ZJ0RTmzdQm+qZTRjPLpc819r90XMkG7Y44= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772154756; c=relaxed/simple; bh=wh4v3IHBfAGzfuyhHvbdamOWJw+DRw+WO6KelYG3s2w=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=UENvaI2XvpYqrKDZfsbtkqUMTTd7k3vetNU7bQ2pBKw7vnqMGjvkKmpPuF1KTB0Sto6GDw6otSGJpE20+b4S2+mNLxIafmAfDGEM+Ml0XeAfPkc8o7OUCFRp8rNloxRjYczJe8SBREUDGWAmF1dUUMGAyEi5vzoAJpv0NRfm7PM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=mit.edu; spf=pass smtp.mailfrom=mit.edu; dkim=pass (2048-bit key) header.d=mit.edu header.i=@mit.edu header.b=bqMH3Kp+; arc=none smtp.client-ip=18.9.28.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=mit.edu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=mit.edu Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=mit.edu header.i=@mit.edu header.b="bqMH3Kp+" Received: from macsyma.thunk.org (pool-173-48-102-61.bstnma.fios.verizon.net [173.48.102.61]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 61R1C15E023721 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 26 Feb 2026 20:12:02 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mit.edu; s=outgoing; t=1772154724; bh=R2yazrm+uYXCsUHQxulDOl6b+SzQHvW4YF3cSW1XWsA=; h=Date:From:Subject:Message-ID:MIME-Version:Content-Type; b=bqMH3Kp+jJ5gT6DPYFXyw1zHde5vRx4+4ZaOHGeGOvZvCcKEIsKEiN54oLnDZb8P2 7qMxDs1Ca1AzvpjjenmqzmhSXAQKG2PTa2+abJXJvcZZPH3M65VJa6hAyzQN3W0IY4 3u62Ee3BEGlEidiPO8NCyAxpMIGBKfHr91LduFANrFIwiipfDiPfa//USz3sRpJ1lK fl8dwcZ162ij8OcX76F1Ij89Yxxq295i2ddOL4s0Cg4ruZSPBVdQF6fI5mQdNyur1N CecPdFODqjc3oshenGxTei8DpZHi8tS1lnmsJLUK259wqzTugObvR1rcRSXcnFnU9E 5DHe7sf5JnHGg== Received: by macsyma.thunk.org (Postfix, from userid 15806) id EBF105A187FC; Thu, 26 Feb 2026 20:12:00 -0500 (EST) Date: Thu, 26 Feb 2026 20:12:00 -0500 From: "Theodore Tso" To: Mario Lohajner Cc: Andreas Dilger , libaokun1@huawei.com, adilger.kernel@dilger.ca, linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, yangerkun@huawei.com, libaokun9@gmail.com Subject: Re: [PATCH] ext4: rralloc - (former rotalloc) improved round-robin allocation policy Message-ID: <20260227011200.GA68551@macsyma-wired.lan> References: <20260225201520.220071-1-mario_lohajner.ref@rocketmail.com> <20260225201520.220071-1-mario_lohajner@rocketmail.com> <20260226024819.GA39209@macsyma-wired.lan> <04dfeda0-8c13-4233-b631-d8912d4fe6f0@rocketmail.com> Precedence: bulk X-Mailing-List: linux-ext4@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <04dfeda0-8c13-4233-b631-d8912d4fe6f0@rocketmail.com> On Thu, Feb 26, 2026 at 10:50:29PM +0100, Mario Lohajner wrote: > The primary purpose of rralloc is to improve allocation distribution > and avoid hotspotting. Performance improvements are not the goal here... You haven't explained *why* allocation distribution and avoiding hotspotting is something we should care about. If it's not performance, then why? How does reducing hotspotting improve things for the user? Why should we care about this goal that apparently is so important to you? - Ted